JP2002298125A - Device, method and program for image simulation, and computer readable recording medium with the program recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To estimate and evaluate the output image quality including characteristics of the distribution of the reflectance of the output image, the difference in dot fluctuation by the image data with high accuracy in a short time. SOLUTION: An image simulator mainly comprises an input image storage means 102, a dot position calculating means 105 for calculating the dot position of a pixel in question based on the pixel data, a dot reflectance distribution data calculating means 104 for calculating the distribution data from the pixel data of the pixel in question, and a reflectance distribution calculating means 106 for calculating the reflectance distribution data of the estimated image based on the dot position of each pixel calculated by the dot position calculating means 105 and the distribution data of each pixel calculated by the dot reflectance distribution data calculating means 104.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention calculates the dot position of a pixel of interest based on the input image data when recording the input image data and simulating the recording output.
Image simulation that calculates distribution data of dot reflectance from pixel data of a target pixel, and calculates expected reflectance distribution data of an image based on the calculated dot position of each pixel and the calculated distribution data of each pixel. The present invention relates to an apparatus, an image simulation method, a program for causing a computer to execute the image simulation method, and a computer-readable recording medium on which the program is recorded.

[0002]

2. Description of the Related Art Conventionally, image quality is generally evaluated by the observer's subjectivity and is usually qualitative. However, this subjective and qualitative image quality has long been objectively and quantitatively evaluated. Attempts have been made to do so.

For example, a method of quantifying image noise (roughness due to density unevenness occurring in an image which should have uniform density) disclosed in Japanese Patent Application Laid-Open No. 1-286084 is disclosed in Japanese Patent Application Laid-Open No. 1-286084. Is subjected to a two-dimensional Fourier transform, then converted to a one-dimensional image, corrected using visual spatial frequency characteristics, and the integrated value is used as image noise. This weights the frequency components that are easily noticeable in the noise to improve the correspondence between the subjective roughness and the objective evaluation amount.

[0004] As described above, the quantitative evaluation method of the image quality can improve the correlation between the subjective image quality and the objective physical quantity by correcting the measured physical quantity with the human visual characteristic. A similar method is used for evaluating the jaggedness and the sharpness of the oblique line of the digital output device.

Japanese Patent Application Laid-Open No. 10-023191 also reads an image to be evaluated by a general-purpose scanner and obtains image noise. The development of the image quantification method as described above makes it possible to quantitatively evaluate the image quality.

[0006]

However, to quantitatively evaluate the image quality, it has been necessary to optically read the image to be evaluated by an image input device such as a scanner or a microdensitometer. In addition, since high-precision and high-resolution reading is required for evaluation, a sufficient speed cannot be obtained at the time of image capturing, and it may take a very long time to evaluate the image quality.

[0007] Further, in order to carry out the evaluation, a target image recording apparatus is required. In product development, it is indispensable that the recording apparatus has been developed to a certain extent and the image output is at a level that enables image output. However, it is not possible to predict the image quality of the recording device at the beginning of development. For example, when developing an image processing method for an image recording device under development, it is not possible to evaluate the quality of the image processing method even if it is started simultaneously with the development of the image recording device. There is.

[0008] In addition, the specifications of the developed recording device have been partially changed.
In order to confirm whether or not the image quality is improved when (for example, the recording density of the recording apparatus is changed), it may take time to evaluate the actual production of the recording apparatus with the changed specifications. Therefore, for example, instead of actually outputting the image, the reflectance distribution of the output image output from the image recording apparatus is calculated based on the dot reflectance distribution data of the image recording apparatus to be evaluated, and the image is output from a printer or the like. Although the image quality of the recording apparatus is predicted, the evaluation is performed in a short time, and the recording characteristics of the electrophotographic image recording apparatus may become unstable.

In particular, the tendency is remarkable in an isolated dot, and the position of the dot and the dot reflectivity distribution may fluctuate relatively largely. One of the biggest factors of image quality deterioration of the output image is considered to be caused by the fluctuation of the dot, which is the minimum constituent unit. Is calculated, it may be difficult to accurately predict image quality such as granularity.

Further, with the recent increase in the density of printers, there is a tendency that it is difficult to faithfully reproduce one isolated dot. This is particularly remarkable in a printer using an electrophotographic recording system. Even in a printer in which one isolated dot is not clearly reproduced, when a certain number of dots are collected, a clear dot is formed. For example, a solid portion is designed so as to obtain a necessary density. When the reflectance distribution of the output image is calculated using the same dot reflectance distribution data regardless of the above, it becomes difficult to simultaneously simulate the low-density image and the high-density image with high accuracy.

In a printing apparatus in which isolated dots are hardly reproduced, when simulating an output image of an isolated dot pattern, variation data of the reflectance distribution of the dots is set to the same amount of variation as that of a pattern other than the isolated dots. In this case, an excessive fluctuation amount is given, and it is impossible to accurately predict the image quality.

According to the present invention, it is possible to highly accurately predict and evaluate the output image quality of a reflectance distribution of an image output from an image recording apparatus, including characteristics of the image recording apparatus such as a difference in a dot variation amount depending on image data. It is an object of the present invention to provide an image simulation device, an image simulation method, an image simulation program, and a computer-readable recording medium recording the program, which enables evaluation in a short time.

[0013]

[MEANS FOR SOLVING THE PROBLEMS] To solve the above-mentioned problems,
In order to achieve the object, an image simulation apparatus according to the invention according to claim 1 includes a recording unit that records input image data, and, when simulating the recording output of the recording unit, a pixel of interest from the input image data. Detecting means for detecting pixel data in the vicinity, position calculating means for calculating the dot position of the pixel of interest based on the detected pixel data, and calculating distribution data from the pixel data of the pixel of interest detected by the detecting means Calculating distribution data of an image to be predicted based on the dot position of each pixel calculated by the position calculation unit and the distribution data of each pixel calculated by the distribution data calculation unit. And a reflectance distribution calculating means.

The image simulation apparatus according to the first aspect of the present invention records input image data, detects pixel data near the target pixel from the input image data when simulating the recording output, and detects the detected pixel data. Calculate the dot position of the target pixel based on the pixel data obtained, calculate distribution data from the detected pixel data of the target pixel, and calculate the distribution position of each pixel and the calculated distribution data of each pixel. Calculate the reflectance distribution data of the expected image, and calculate the reflectance distribution of the image output from the image recording device with high accuracy of the output image quality, including the characteristics of the image recording device such as differences in the amount of dot fluctuation due to the image data. It is possible to perform accurate prediction and evaluation, and to enable evaluation in a short time.

According to a second aspect of the present invention, in the image simulation apparatus according to the first aspect, the position calculating means further includes a state of pixel data adjacent to the pixel of interest detected by the detecting means. And calculating a dot position of the pixel of interest by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density.

In the image simulation apparatus according to the second aspect of the present invention, a predetermined position is determined with respect to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the detected neighboring pixel data of the target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the image recording device, and the reflectance distribution of the image output from the image recording device is converted to the output image quality including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. It is possible to perform highly accurate prediction and evaluation, and to enable evaluation in a short time.

According to a third aspect of the present invention, there is provided the image simulation apparatus according to the first aspect, wherein the distribution data calculating means further comprises: The method is characterized in that a predetermined amount of variation is added to the basic reflectance distribution data based on the state to calculate the dot reflectance distribution data for the pixel of interest.

In the image simulation apparatus according to the third aspect of the present invention, a predetermined amount of variation is added to the basic reflectance distribution data based on the detected state of the neighboring pixel data of the target pixel, and the dot reflection for the target pixel is performed. Calculate the rate distribution data and calculate the reflectance distribution of the image output from the image recording apparatus with high accuracy prediction of the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot variation by the image data
Evaluation can be performed, and evaluation can be performed in a short time.

According to a fourth aspect of the present invention, there is provided the image simulation apparatus according to the first aspect, wherein the reflectance distribution calculating means further calculates the dot position of each pixel calculated by the position calculating means. And calculating a reflectance distribution of an image expected to be output from the recording means with respect to input image data based on the dot reflectance distribution data of each pixel calculated by the distribution data calculating means. And

According to a fourth aspect of the present invention, in the image simulation apparatus, the input image data is calculated based on the calculated dot position of each pixel and the dot reflectance distribution data of each pixel calculated by the distribution data calculating means. The reflectance distribution of the image expected to be output from the recording means is calculated for the image recording apparatus, and the reflectance distribution of the image output from the image recording apparatus is calculated based on the image data. High-precision prediction and evaluation of output image quality including characteristics can be performed, and evaluation can be performed in a short time.

According to a fifth aspect of the present invention, there is provided the image simulation apparatus according to the first or fourth aspect, wherein the reflectance distribution calculating means further stores the calculated reflectance distribution. The image forming apparatus further includes a deterioration characteristic correction unit that corrects according to one or more deterioration characteristics related to image formation of the recording unit.

An image simulation apparatus according to a fifth aspect of the present invention corrects the calculated reflectance distribution according to one or more deterioration characteristics relating to image formation of the recording means, and outputs the corrected reflectance distribution from the image recording apparatus. Highly accurate prediction of the output image quality, including the characteristics of the image recording device, such as the difference in the amount of dot variation due to image data,
Evaluation can be performed, and evaluation can be performed in a short time.

According to a sixth aspect of the present invention, there is provided an image simulation apparatus, wherein a recording means for recording input image data, and when the recording output of the recording means is simulated, the recording means is located near a pixel of interest from the input image data. Detecting means for detecting pixel data; position calculating means for calculating the dot position of the pixel of interest based on the detected pixel data; and density, brightness, brightness, etc., based on the pixel data of the pixel of interest detected by the detecting means. Specific physical quantity distribution means for obtaining the distribution of the specific physical quantity of the image output from the recording means based on the specific physical quantity.

According to the image simulation apparatus of the present invention, when recording the input image data and simulating the recording output, the image simulation apparatus detects pixel data near the target pixel from the input image data and detects the pixel data. The dot position of the pixel of interest is calculated based on the pixel data thus obtained,
A distribution of a specific physical quantity of an image recorded and output based on a specific physical quantity such as density, lightness, and luminance is obtained from the detected pixel data of the target pixel, and a reflectance distribution of the image output from the image recording apparatus is obtained. This enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording apparatus such as differences in the amount of dot fluctuation due to image data, and enables evaluation in a short time.

According to a seventh aspect of the present invention, in the image simulation apparatus according to the sixth aspect, the position calculating means further includes a state of pixel data adjacent to the pixel of interest detected by the detecting means. And calculating a dot position of the pixel of interest by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density.

In the image simulation apparatus according to the present invention, a predetermined position of the basic dot position calculated from the recording density data corresponding to the recording density is determined based on the detected state of the neighboring pixel data of the target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the image recording device, and the reflectance distribution of the image output from the image recording device is converted to the output image quality including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Enables highly accurate prediction and evaluation, and enables evaluation in a short time.

According to an eighth aspect of the present invention, there is provided an image simulation apparatus, comprising: a recording unit for recording input image data; and, when simulating a recording output of the recording unit, a dot position of a pixel of interest from the input image data. Position calculating means for calculating, reflectance distribution data calculating means for calculating dot reflectance distribution data of the pixel of interest, dot position of each pixel detected by the detecting means, calculated by the reflectance distribution data calculating means. Using the dot reflectance distribution data of each pixel, a reflectance distribution calculation unit that calculates a reflectance distribution of an image output from the recording unit with respect to input image data, and a reflectance distribution calculation unit that calculates the reflectance distribution. Reflectance variation data adding means for adding reflectance variation data according to the characteristics of the image output target to the reflectance distribution of the image , Characterized by comprising a.

The image simulation apparatus according to the invention of claim 8 records the input image data, calculates the dot position of the pixel of interest from the input image data when simulating the recording output, and calculates the dot position of the pixel of interest. The reflectance distribution data is calculated, and the dot position of each pixel detected and the dot reflectance distribution data of each pixel calculated by the reflectance distribution data calculation means are used to calculate the image recorded and output with respect to the input image data. A reflectance distribution is calculated, reflectance reflectance data according to the characteristics of the image output target is added to the calculated reflectance distribution of the image, and the reflectance distribution of the image output from the image recording apparatus is calculated based on the image data. Enables highly accurate prediction and evaluation of output image quality, including the characteristics of the image recording device such as differences in dot fluctuation amount, and enables evaluation in a short time.

According to a ninth aspect of the present invention, in the image simulation apparatus according to the eighth aspect, the position calculating means further comprises recording density data corresponding to a recording density and dot position variation data. A dot position of each pixel is calculated.

The image simulation apparatus according to the ninth aspect of the present invention calculates the recording density data corresponding to the recording density, the fluctuation data of the dot position, and the dot position of each pixel in the position calculation, and outputs from the image recording apparatus. It is possible to accurately predict and evaluate the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation depending on the image data, and to evaluate the reflectance distribution of the image to be obtained in a short time. .

An image simulation apparatus according to a tenth aspect of the present invention is the image simulation apparatus according to the ninth aspect, wherein the reflectance distribution data calculating means further includes basic dot reflectance data and dot reflectance variation data. Then, dot reflectance distribution data of each pixel is calculated from the following.

The image simulation apparatus according to the tenth aspect of the invention calculates the dot reflectance distribution data of each pixel from the basic dot reflectance data and the dot reflectance variation data in calculating the reflectance distribution data. In addition, the reflectance distribution of the image output from the image recording device can be accurately estimated and evaluated in a short time by including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Can be evaluated.

According to an eleventh aspect of the present invention, in the image simulation apparatus of the eighth aspect, further, the reflectance distribution calculated by the reflectance variation data adding means is stored in an image of the recording means. It is characterized by having deterioration characteristic correction means for correcting according to one or more deterioration characteristics related to formation.

The image simulation apparatus according to the present invention corrects the reflectance distribution calculated by adding the reflectance variation data according to one or more deterioration characteristics relating to image formation of the recording means, Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation depending on the image data, and evaluates the reflectance distribution of the image output from the image recording device in a short time Can be.

According to a twelfth aspect of the present invention, there is provided an image simulation apparatus, comprising: a recording unit for recording input image data; and, when simulating a recording output of the recording unit, pixel data in the vicinity of a target pixel from the input image data. And a position calculating unit that calculates the dot position of the pixel of interest based on the detected pixel data,
Specific physical quantity distribution means for obtaining the distribution of the specific physical quantity of the image output from the recording means based on specific physical quantities such as density, brightness, and luminance from the pixel data of the target pixel detected by the detection means, It is characterized by having.

The image simulation apparatus according to the twelfth aspect of the present invention, when recording input image data and simulating recording output, detects pixel data in the vicinity of the pixel of interest from the input image data and detects the pixel data. The dot position of the target pixel is calculated based on the obtained pixel data, and the density, brightness,
The distribution of the specific physical quantity of the image recorded and output based on the specific physical quantity such as the luminance is obtained, and the reflectance distribution of the image output from the image recording apparatus is determined based on the image data such as the difference in the amount of dot fluctuation due to the image data. The output image quality including the characteristics of the recording apparatus can be predicted and evaluated with high accuracy, and the evaluation can be performed in a short time.

An image simulation method according to a thirteenth aspect of the present invention provides a recording step of recording input image data and, when simulating a recording output of the recording step, the input image data is located near a pixel of interest from the input image data. A detecting step of detecting pixel data, a position calculating step of calculating a dot position of the pixel of interest based on the detected pixel data, and distribution data of calculating distribution data from pixel data of the pixel of interest detected in the detecting step A calculating step, and a reflectance distribution for calculating an expected reflectance distribution data of the image based on the dot position of each pixel calculated in the position calculating step and the distribution data of each pixel calculated in the distribution data calculating step. And a calculating step.

According to the image simulation method of the present invention, when recording the input image data and simulating the recording output, pixel data near the target pixel is detected from the input image data, and the detection is performed. The dot position of the target pixel is calculated based on the obtained pixel data, the distribution data is calculated from the detected pixel data of the target pixel, and the dot position of each pixel calculated by the position calculation and the calculated distribution data of each pixel are calculated. Calculate the expected reflectance distribution data of the image based on the pixel distribution data, and calculate the reflectance distribution of the image output from the image recording device, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. This enables highly accurate prediction and evaluation of the output image quality, and enables evaluation in a short time.

The image simulation method according to a fourteenth aspect of the present invention is the image simulation method according to the thirteenth aspect, further comprising the step of:
Calculate the dot position of the target pixel by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the neighboring pixel data of the target pixel detected in the detection step The distribution data calculation step calculates dot reflectance distribution data for the target pixel by adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the neighboring pixel data of the target pixel detected in the detection step. And the reflectance distribution calculating step,
Based on the dot position of each pixel calculated in the position calculation step and the dot reflectance distribution data of each pixel calculated in the distribution data calculation step, it is expected that the input image data will be output from the recording step. And calculating the reflectance distribution of the image.

According to a fourteenth aspect of the present invention, there is provided the image simulation method according to the first aspect of the invention, wherein a predetermined position is determined for a basic dot position calculated from recording density data corresponding to the recording density based on the state of the detected neighboring pixel data of the target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the target pixel, and the distribution data calculating step adds a predetermined variation amount to the basic reflectance distribution data based on the state of the pixel data in the vicinity of the detected pixel of interest. Calculating the dot reflectance distribution data for the pixel; and in the reflectance distribution calculating step, when the input image data is recorded and output based on the calculated dot position of each pixel and the calculated dot reflectance distribution data of each pixel. The reflectance distribution of the expected image is calculated, and the reflectance distribution of the image output from the image recording apparatus is recorded in the image recording such as the difference in the amount of dot fluctuation due to the image data. Enables highly accurate prediction and evaluation of the output image quality including the characteristics of the device, and reflects the reflectance distribution of the image output from the image recording device, including the characteristics of the image recording device such as differences in the amount of dot variation due to image data. This enables highly accurate prediction and evaluation of the output image quality, and enables evaluation in a short time.

According to a fifteenth aspect of the present invention, there is provided the image simulation method according to the thirteenth or fourteenth aspect, further comprising the step of calculating the reflectance distribution. And a deterioration characteristic correcting step of correcting according to one or more deterioration characteristics related to image formation in the recording step.

According to a fifteenth aspect of the present invention, in the reflectance distribution calculating step, the calculated reflectance distribution is corrected according to one or more deterioration characteristics related to image formation in the recording step. In addition, the reflectance distribution of the image output from the image recording device can be accurately estimated and evaluated in a short time by including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Can be evaluated.

According to a sixteenth aspect of the present invention, in the image simulation method, a recording step of recording input image data, and when simulating the recording output of the recording step, the input image data is located near a pixel of interest from the input image data. A detecting step of detecting pixel data; a position calculating step of calculating a dot position of the target pixel based on the detected pixel data; and a density, brightness, luminance, etc., based on the pixel data of the target pixel detected in the detecting step. A specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of the image output from the recording step based on the specific physical quantity.

In the image simulation method according to the present invention, the input image data is recorded, and when simulating the recording output, the pixel data near the target pixel is detected from the input image data, and the detected pixel data is detected. The dot position of the target pixel is calculated based on the detected pixel data. The density, brightness,
The distribution of the specific physical quantity of the image recorded and output based on the specific physical quantity such as the luminance is obtained, and the reflectance distribution of the image output from the image recording apparatus is determined based on the image data such as the difference in the amount of dot fluctuation due to the image data. The output image quality including the characteristics of the recording apparatus can be predicted and evaluated with high accuracy, and the evaluation can be performed in a short time.

An image simulation method according to a seventeenth aspect of the present invention is the image simulation method according to the sixteenth aspect, further comprising:
Calculate the dot position of the target pixel by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the neighboring pixel data of the target pixel detected in the detection step It is characterized by doing.

According to a seventeenth aspect of the present invention, in the image simulation method, a predetermined dot position is calculated for a basic dot position calculated from recording density data corresponding to a recording density based on the state of pixel data adjacent to the detected target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the image recording device, and the reflectance distribution of the image output from the image recording device is converted to the output image quality including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Enables highly accurate prediction and evaluation, and enables evaluation in a short time.

According to the image simulation method of the present invention, a dot position of a pixel of interest is calculated from the input image data when simulating a recording step of recording input image data and a recording output of the recording step. A position calculation step, a reflectance distribution data calculation step of calculating dot reflectance distribution data of the pixel of interest, a dot position of each pixel detected in the detection step, and a dot of each pixel calculated in the reflectance distribution data calculation step Using the reflectance distribution data, a reflectance distribution calculating step of calculating a reflectance distribution of an image output from the recording step with respect to the input image data, and a reflectance distribution of the image calculated in the reflectance distribution calculating step. A reflectance variation data adding step of adding reflectance variation data according to the characteristics of the image output target,
It is characterized by including.

According to the image simulation method of the present invention, in the recording step of recording the input image data, and when simulating the recording output of the recording step, the dot position of the pixel of interest is calculated from the input image data. Position calculating step, a reflectance distribution data calculating step of calculating dot reflectance distribution data of the pixel of interest, a dot position of each pixel detected in the detecting step, and a pixel position of each pixel calculated in the reflectance distribution data calculating step. A reflectance distribution calculating step of calculating a reflectance distribution of an image output from the recording step with respect to the input image data using the dot reflectance distribution data; and a reflectance distribution of the image calculated in the reflectance distribution calculating step. Is added to the reflectance variation data according to the characteristics of the image output target, and the reflectance distribution of the image output from the image recording device is added. Accurate prediction of the properties, including the output image quality of an image recording apparatus such as a difference dot fluctuation amount due to the image data, to enable evaluation, can be evaluated in a short time.

According to a nineteenth aspect of the present invention, in the image simulation method according to the eighteenth aspect, the position calculating means further comprises a recording density data corresponding to a recording density and a dot position variation data. Calculating the dot position of each pixel; calculating the dot reflectance distribution data of each pixel from the basic dot reflectance data and the dot reflectance variation data in the reflectance distribution data calculating step; A deterioration characteristic correction step of correcting the reflectance distribution calculated in step (1) according to one or more deterioration characteristics relating to image formation in the recording step.

In the image simulation method according to the nineteenth aspect, in the position calculation, the recording density data corresponding to the recording density, the dot position variation data, and the dot position of each pixel are calculated, and the reflectance distribution data calculation is performed. Calculating the dot reflectance distribution data of each pixel from the basic dot reflectance data and the dot reflectance variation data, and applying the reflectance distribution calculated in the reflectance variation data adding step to the image formation in the recording step. Highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data, and the reflectance distribution of the image output from the image recording device corrected according to the above degradation characteristics , And the evaluation can be performed in a short time.

According to a twentieth aspect of the present invention, there is provided an image simulation method in which a recording step of recording input image data and, when simulating a recording output of the recording step, the input image data are located near a pixel of interest from the input image data. A detecting step of detecting pixel data; a position calculating step of calculating a dot position of the target pixel based on the detected pixel data; and a density, brightness, luminance, etc., based on the pixel data of the target pixel detected in the detecting step. A specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of the image output from the recording step based on the specific physical quantity.

In the image simulation method according to the twentieth aspect, when simulating the recording output in the recording step, pixel data near the pixel of interest is detected from the input image data, and the detected pixel data is detected. , The dot position of the pixel of interest is calculated based on the pixel data of the pixel of interest, and the distribution of the specific physical quantity of the image output from the recording process is obtained based on the specific physical quantities such as density, brightness, and luminance from the detected pixel data. In this way, the reflectance distribution of the image output from the image recording apparatus can be accurately predicted and evaluated for the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data, and the Can be evaluated.

According to an image simulation program of the present invention, when a recording step of recording input image data and a recording output of the recording step are simulated, the image simulation program is located near a pixel of interest from the input image data. A detecting step of detecting pixel data, a position calculating step of calculating a dot position of the pixel of interest based on the detected pixel data, and distribution data of calculating distribution data from pixel data of the pixel of interest detected in the detecting step A calculating step, and a reflectance distribution for calculating an expected reflectance distribution data of the image based on the dot position of each pixel calculated in the position calculating step and the distribution data of each pixel calculated in the distribution data calculating step. And a calculating step.

The image simulation program according to the invention of claim 21 records the input image data and, when simulating the recording output, detects pixel data near the target pixel from the input image data and detects The dot position of the target pixel is calculated based on the obtained pixel data, the distribution data is calculated from the detected pixel data of the target pixel, and the dot position of each pixel calculated by the position calculation and the calculated distribution data of each pixel are calculated. Calculate the expected reflectance distribution data of the image based on the pixel distribution data, and calculate the reflectance distribution of the image output from the image recording device, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. This enables highly accurate prediction and evaluation of the output image quality, and enables evaluation in a short time.

An image simulation program according to a twenty-second aspect of the present invention is the image simulation program according to the twenty-first aspect, wherein the position calculating step further includes a step of determining a state of pixel data adjacent to the target pixel detected in the detecting step. Calculating the dot position of the pixel of interest by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density based on
The distribution data calculation step calculates dot reflectance distribution data for the target pixel by adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the neighboring pixel data of the target pixel detected in the detection step, The reflectivity distribution calculating step includes performing the recording on the input image data based on the dot position of each pixel calculated in the position calculating step and the dot reflectivity distribution data of each pixel calculated in the distribution data calculating step. The method is characterized in that a reflectance distribution of an image expected to be output from the process is calculated.

The image simulation program according to the twenty-second aspect of the present invention is a computer-readable storage medium storing an image simulation program for determining a basic dot position calculated from recording density data corresponding to a recording density based on the detected state of pixel data in the vicinity of a target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the target pixel, and the distribution data calculating step adds a predetermined variation amount to the basic reflectance distribution data based on the state of the pixel data in the vicinity of the detected pixel of interest. Calculating the dot reflectance distribution data for the pixel; and in the reflectance distribution calculating step, when the input image data is recorded and output based on the calculated dot position of each pixel and the calculated dot reflectance distribution data of each pixel. The expected image reflectance distribution is calculated, and the reflectance distribution of the image output from the image recording device is calculated based on the difference in the amount of dot variation due to the image data. Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, and the characteristics of the image recording device, such as differences in the amount of dot variation due to the image data and the reflectance distribution of the image output from the image recording device , Which enables highly accurate prediction and evaluation of the output image quality, and enables evaluation in a short time.

An image simulation program according to the present invention as set forth in claim 23, is an image simulation program according to claim 21 or claim 2.
2. In the image simulation program according to 2,
Further, the reflectance distribution calculation step includes a deterioration characteristic correction step of correcting the calculated reflectance distribution according to one or more deterioration characteristics related to image formation in the recording step.

According to an image simulation program of the present invention, in the reflectance distribution calculating step, the calculated reflectance distribution is corrected in accordance with one or more deterioration characteristics relating to image formation in the recording step. In addition, the reflectance distribution of the image output from the image recording device can be accurately estimated and evaluated in a short time by including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Can be evaluated.

According to a twenty-fourth aspect of the present invention, in the image simulation program, a recording step of recording the input image data, and when simulating the recording output of the recording step, the simulation is performed in the vicinity of the pixel of interest from the input image data. A detecting step of detecting pixel data; a position calculating step of calculating a dot position of the target pixel based on the detected pixel data; and a density, brightness, luminance, etc., based on the pixel data of the target pixel detected in the detecting step. A specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of the image output from the recording step based on the specific physical quantity.

The image simulation program according to the invention of claim 24 records input image data, detects pixel data near the target pixel from the input image data when simulating the recording output, and detects the detected pixel data. Calculating the dot position of the target pixel based on the detected pixel data, the density, brightness, and the distribution of the specific physical amount of the image recorded and output based on the specific physical amount such as the brightness from the detected pixel data of the target pixel. It is possible to accurately predict and evaluate the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot fluctuation due to the image data, and reduce the reflectance distribution of the image output from the image recording device. You can evaluate by time.

An image simulation program according to a twenty-fifth aspect of the present invention is the image simulation program according to the twenty-fourth aspect, further comprising the step of calculating the position of the neighboring pixel data of the pixel of interest detected in the detection step. And calculating a dot position of the pixel of interest by adding a predetermined amount of variation to the basic dot position calculated from the recording density data corresponding to the recording density.

An image simulation program according to the twenty-fifth aspect of the present invention is a computer-readable storage medium storing an image simulation program for determining a basic dot position calculated from recording density data corresponding to a recording density based on a state of detected neighboring pixel data of a target pixel. The dot position of the pixel of interest is calculated by adding the variation amount of the image recording device, and the reflectance distribution of the image output from the image recording device is converted to the output image quality including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. Enables highly accurate prediction and evaluation, and enables evaluation in a short time.

An image simulation program according to a twenty-sixth aspect of the present invention calculates a dot position of a target pixel from input image data when simulating a recording step of recording input image data and a recording output of the recording step. A position calculation step, a reflectance distribution data calculation step of calculating dot reflectance distribution data of the pixel of interest, a dot position of each pixel detected in the detection step, and a dot of each pixel calculated in the reflectance distribution data calculation step Using the reflectance distribution data, a reflectance distribution calculating step of calculating a reflectance distribution of an image output from the recording step with respect to the input image data, and a reflectance distribution of the image calculated in the reflectance distribution calculating step. A reflectance variation data adding step of adding reflectance variation data according to the characteristics of the image output target. And butterflies.

The image simulation program according to the twenty-sixth aspect of the present invention provides a recording step of recording input image data and calculating a dot position of a pixel of interest from the input image data when simulating a recording output of the recording step. Position calculating step, a reflectance distribution data calculating step of calculating dot reflectance distribution data of the pixel of interest, a dot position of each pixel detected in the detecting step, and a pixel position of each pixel calculated in the reflectance distribution data calculating step. A reflectance distribution calculating step of calculating a reflectance distribution of an image output from the recording step with respect to the input image data using the dot reflectance distribution data; and a reflectance distribution of the image calculated in the reflectance distribution calculating step. To reflect the fluctuation of the reflectance of the image output from the image recording device. Distribution highly accurate prediction of output image quality, including the characteristics of the image recording apparatus such as a difference in the dot variation of the image data, to enable evaluation, can be evaluated in a short time.

An image simulation program according to a twenty-seventh aspect of the present invention is the image simulation program according to the twenty-sixth aspect, wherein the position calculating means further comprises recording density data corresponding to recording density and dot position variation data. Calculating the dot position of each pixel; calculating the dot reflectance distribution data of each pixel from the basic dot reflectance data and the dot reflectance variation data in the reflectance distribution data calculating step; A deterioration characteristic correction step of correcting the reflectance distribution calculated in step (1) according to one or more deterioration characteristics relating to image formation in the recording step.

The image simulation program according to the twenty-seventh aspect of the present invention calculates the reflectance distribution data by calculating the recording density data corresponding to the recording density, the fluctuation data of the dot position, and the dot position of each pixel in the position calculation. Calculating the dot reflectance distribution data of each pixel from the basic dot reflectance data and the dot reflectance variation data, and applying the reflectance distribution calculated in the reflectance variation data adding step to the image formation in the recording step. Highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data, and the reflectance distribution of the image output from the image recording device corrected according to the above degradation characteristics , And the evaluation can be performed in a short time.

An image simulation program according to the invention of claim 28 is a recording step of recording input image data, and when simulating a recording output of the recording step, the image simulation program is located near a pixel of interest from the input image data. A detecting step of detecting pixel data; a position calculating step of calculating a dot position of the target pixel based on the detected pixel data; and a density, brightness, luminance, etc., based on the pixel data of the target pixel detected in the detecting step. A specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of the image output from the recording step based on the specific physical quantity.

According to the image simulation program of the present invention, when simulating the recording output in the recording step, pixel data near the pixel of interest is detected from the input image data, and the detected pixel data , The dot position of the pixel of interest is calculated based on the pixel data of the pixel of interest, and the distribution of the specific physical quantity of the image output from the recording process is obtained based on the specific physical quantities such as density, brightness, and luminance from the detected pixel data. In this way, the reflectance distribution of the image output from the image recording apparatus can be accurately predicted and evaluated for the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data, and the Can be evaluated.

As described above, according to the program according to the present invention, the reflectance distribution of the image output from the image recording apparatus can be determined by using the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data. This enables highly accurate prediction and evaluation of the output image quality, and enables evaluation in a short time.

According to a twenty-ninth aspect of the present invention, there is provided a computer-readable recording medium having recorded thereon a program.

According to the recording medium of the present invention, the reflectance distribution of the image output from the image recording apparatus can be adjusted based on the characteristics of the image recording apparatus such as differences in the amount of dot fluctuation due to image data. Precise prediction of quality,
Enables evaluation and enables quick evaluation

[0072]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of an image simulation apparatus, an image simulation method, and an image simulation method program according to the present invention. The form will be described in detail.

[First Embodiment] First, the configuration of an entire image simulation system including an image simulation apparatus according to an embodiment of the present invention will be described.

(Configuration of Image Simulation System)
FIG. 1 is a diagram illustrating a block configuration of the image simulation system according to the first embodiment of the present invention.

First, the image simulation system 10
The data required for the image simulation processing is input to the 0 image input unit 101. The input data is at least temporarily stored in the input image storage unit 102.

The reflectance distribution (or other specificity) of an image that will be output when certain image data is input to an image recording device (not shown) (not shown) that is a target device of the simulation. The purpose of this is to obtain image data (input image data).

The image recording apparatus is also supplied with recording density data and basic reflectance distribution data as basic specification data. However, when calculating the reflectance distribution of an output image with respect to certain image data, if the previously input recording density data and basic reflectance distribution data can be used as they are, only image data needs to be input.

Conversely, when it is desired to simulate an output image by changing the recording density data and / or the dot reflectance distribution data using the same image data,
The image data is not required to be input again.

As input image data, when the target device is a binary image recording device, dots are ON or OFF.
Is a 1-bit / pixel data string representing 0 or 1, or 8 bi representing 0 or 255 whether the dot is ON or OFF.
This is a data string of t / pixel, and in the case of a multi-valued image recording apparatus, a data string representing the size or density of a dot by a plurality of bits (usually 8 bits / pixel). The recording density data generally indicates the resolution of the image recording apparatus in dpi (dot)
(per inch).

The calculating means 103 includes a dot reflectivity distribution data calculating means 104 for calculating dot reflectivity distribution data from the dot reflectivity fluctuation data 107 and the basic dot reflectivity distribution data 108, a recording density 109 and dot position fluctuation data 110. And a dot distribution calculating means 106 for calculating a dot distribution based on the result of the dot reflectivity distribution data calculating means 104 and the result of the dot position calculating means 105. . Further, the reflectance distribution variation adding means 112 makes a reflectance distribution 113 based on the result of the reflectance distribution calculating means 106.

When simulating an output image of an image recording apparatus for forming a color image, data of each component of the color image is input as input image data (if necessary, the dot reflectance distribution data is also input to each component). Prepared separately). In the following description, unless otherwise specified, the input image data has dots ON or OFF.
It is assumed that the image data is binary image data representing 0 or 1.

FIG. 2 is a diagram showing the basic reflectance distribution data in FIG. The basic reflectance distribution data (FIG. 2) is prepared in advance based on the measurement result of the output image or based on prediction / estimation.
And basic data for calculating the distribution up to the distance 201 from the dot center.

The basic reflectance distribution data is actually obtained by, for example, a function (for example, the form of f (r) or f (x, y)) using the distance 201 from the center of the dot and the x and y coordinates as variables or Given in the form of a two-dimensional lookup. After the necessary data is input, a repetitive process for each pixel of the input image data described below with reference to FIG. 1 starts. In addition, there are some input data as described below, which will be added as necessary.

First, one pixel in the input image data is selected as a target pixel, and it is determined whether the target pixel is ON (1). This determination is made by, for example, the reflectance distribution calculating means 106 in FIG. If the target pixel is OFF (0), that pixel is ignored, the process returns to target pixel selection, and the next target pixel is selected. If the target pixel is ON,
Pixel data adjacent to the pixel of interest is detected from the input image data.

The neighboring pixel data indicates the state of pixel data in the vicinity of the target pixel. For example, in the simplest case, one of the upper, lower, left, and right neighboring pixel data of the target pixel is ON.
, 1 when all adjacent pixel data is OFF
Output.

The dot position of the target pixel is determined with respect to the basic dot position at which dots are to be printed based on the recording density data (disposed at equal pitches in both x and y directions at a reciprocal pitch of the recording density). The calculation is performed by adding a predetermined fluctuation amount based on the state of the neighboring pixel data.

The calculation of the dot position is performed by the dot position calculating means 105 in FIG.
The basic dot reflectivity distribution data 108 of the target pixel, that is, data representing the reflectivity distribution of dots recorded corresponding to the target pixel is the basic dot reflectivity distribution data 108.
Is calculated by adding a predetermined amount of variation based on the neighboring pixel data of each pixel.
The basic dot reflectance distribution data 108 is attached to a dot position corresponding to the target pixel.

The basic dot reflectance distribution data 108 is stored in association with the dot position. In FIG. 1, the calculation of the basic dot reflectance distribution data 108 is performed by the dot reflectance distribution data calculating means 104, and the sticking of the target pixel to the dot position is performed by the reflectance distribution calculating means 106. I have.

The addition of the amount of variation based on the neighboring pixel data when calculating the dot position and dot reflectance data is performed as needed.
Either or both of them can be omitted, and are set according to the purpose of the simulation or according to the characteristics of the image recording apparatus.

Further, regardless of whether the target pixel is ON or OFF, detection of neighboring pixel data, calculation of dot reflectance distribution data based on the state of the neighboring pixel data, and calculation of dot position are performed by the calculating means 103. ,
Only when the target pixel is ON, the calculated dot reflectance distribution data may be attached to the corresponding dot position.

The calculation of the neighboring pixel data is performed by the method described above,
Alternatively, more generally, pixel data (0 or 1) of about 1 to 10 pixels around the target pixel is detected, and a weight corresponding to the distance from the target pixel, for example, k of the distance from the target pixel is detected. The weight is multiplied by a power (k> 1) and added.

FIG. 3 is an explanatory diagram schematically showing one example of the specific calculation method. In FIG. 3, the recording density 300 is a size of 4015 × 5 and the distance from the target pixel is
A mask having a weight of the square of (unit: pixel) is set. In the dot position calculation unit 301,
Each component of the mask corresponding to the image data in the vicinity of the target pixel is calculated by the basic dot position calculation 302. Further, the dot position variation 303 is multiplied by the normal random number 304.

The result of the dot position calculation unit 301 and the output of the multiplier 305 are added by the adder 306, whereby
23/40 neighboring pixel data is calculated for the target pixel. In the calculation of the dot position 310, a dot amount to be applied to each pixel is calculated by adding a predetermined variation amount based on neighboring pixel data to the basic dot position.

FIG. 4 is a characteristic diagram showing the relationship between the spatial frequency and the amplitude of fluctuation in the system shown in FIG. FIG.
, A peak characteristic starts at a low-frequency fluctuation 402, a periodic position fluctuation 403 due to a paper feed speed fluctuation, and a spatial frequency 400 exhibits a drooping characteristic at a random high-frequency fluctuation 404.

As described above, the reflectance is used as the physical quantity of the output image finally obtained, but the distribution may be obtained by using any other physical quantity such as density and lightness. In that case, the "reflectance" used in the following description, such as reflectance distribution, dot reflectance distribution data, dot reflectance distribution variation data, and reflectance distribution correction data, is used for density, brightness, etc. What is necessary is just to read "physical quantity".

FIG. 5 is a diagram showing an example of the internal configuration of the dot position calculating means in FIG. As shown in FIG. 5, the dot position calculating means 5 when the spatial frequency characteristic of the dot position fluctuation is given as basic dot position fluctuation data
00 is the internal configuration. The basic dot position calculation 501 is
The calculation is performed based on the data of the recording density 502. On the other hand, white noise is generated by the white noise generating means 503, and this is subjected to fast Fourier transform (FFT) by the FFT means 504.

This converted data is supplied to the inverse FFT processing means 506.
Performs an inverse FFT process. As a result, noise having the desired spatial frequency characteristic, that is, the amount of fluctuation of the dot position 510 is generated.

The fluctuation amount of the dot position 510 is corrected, for example, by a position fluctuation amount correction unit based on the neighboring pixel data, and is added to the basic dot position by adding means. In this way, the dot position 110 to which the position variation according to the dot position variation data (spatial frequency characteristic) 507 is added is obtained, and this is given to the reflectance distribution calculation unit.

FIG. 6 is a diagram showing a variation amount according to the characteristics of the image recording apparatus. FIG. 6 shows the characteristics of the reflectance 600 and the distance 601 from the dot center.
03 and the basic dot reflectivity distribution data 602, the dot reflectivity distribution is calculated based on the neighboring pixel data by using at least one of the intensity and size of the basic dot reflectivity distribution data 602 as a characteristic of the image recording apparatus. A corresponding variation 603 is added.

FIG. 7 is a diagram showing the amount of fluctuation according to the characteristics of the image recording apparatus. The dot reflectivity distribution is calculated based on neighboring pixel data based on neighboring pixel data, and is calculated based on a characteristic amount of the reflectivity 700 and a distance 701 from the dot center according to the characteristics of the image recording apparatus. On the other hand, a variation 703 corresponding to the characteristics of the image recording apparatus is added to at least one of the intensity and the size. As described above, the dot reflectance distribution data to be applied to the target pixel can be calculated.

FIG. 8 is an explanatory view schematically showing one example of a specific calculation method. The dot reflectance distribution data calculation unit 820 is dot reflectance variation data composed of the basic variation data 800 of the dot size variation 801 and the dot intensity variation 802. This is one of the basic data of the variation amount of the dot reflectivity distribution based on the data, or one of the input data that can be arbitrarily input.

Here, the dot size variation 801 and the dot intensity variation 802 are, for example, the standard deviation of the dot size variation 801 and the dot intensity variation 802, respectively.
These basic reflectance fluctuation amounts are respectively corrected based on the neighboring pixel data of each pixel.

[0103] The normal random numbers 803 and 804 are
After the multiplication at 5, 806, the variation is added to the basic dot reflectance distribution data 807 by the calculation units 808, 809. As described above, the reflectance distribution calculator 810 calculates the dot reflectance distribution data of each dot.

As described above, the addition of these fluctuations is performed in the calculation units 808 and 809. A normal random number of 80 is used for the standard deviation of the reflectance distribution variation.
By multiplying by 3,804, it is possible to satisfactorily reproduce the dot reflectance variation when the spatial frequency dependence of the variation amount of the dot reflectance distribution is low.

Further, the variation of the dot reflectance distribution is corrected based on the neighboring pixel data according to the characteristics of the image recording apparatus. In an output device that is larger than in the case of the above, the dot reflectance distribution variation is smaller for pixels with larger neighboring pixel data so that the variation in dot reflectance distribution is relatively larger for pixels with smaller neighboring pixel data. The correction is made as follows.

Conversely, for an output device in which isolated dots are hardly reproduced, correction is made so that the variation in dot reflectance distribution is reduced for pixels with small neighboring pixel data.

FIG. 9 schematically shows another example of the specific calculation method in FIG. The reflectance calculation pitch 900 is at the dot recording pitch 901 and is applied to an output device in which the reproduction of one isolated dot is weak.
A step of correcting the intensity or size of the basic reflectance distribution data by the neighboring pixel data is added. The dots A and B are shown.

A simulation result for certain input image data, that is, a reflectance distribution of an output image is schematically shown as a grayscale image. In FIG. 9, regularly arranged black points indicate basic dot positions at which dots calculated based on the recording density data are to be recorded.

A dot is recorded at the dot position of each dot obtained by adding a predetermined amount of variation to the basic dot position when the pixel corresponding to that dot position is ON.
As described above, the reflectance distribution data calculated based on the state of the neighboring pixel data of the corresponding pixel is attached to the dot position.

The reflectivity distribution calculating means 106 in FIG. 1 calculates the reflectivity of each point at a pitch finer than the recording density, as schematically shown by broken lines in FIG. For example, when determining the reflectance of the point a, the calculation is performed based on the distance or coordinates from the center of the closer dot A and the dot reflectance distribution data attached to the dot position.

When the dot reflectance distribution data is given by the above function, the reflectance is calculated by substituting the center or the calculated distance or coordinates from the dot position of the dot A into the function. .

At points such as point b which are affected by dots A and B, generally a plurality of dots, the dot reflectance distribution data affixed to dot A and the center of dot A Calculates the reflectivity of point b using the distance or coordinates of point b, and calculates the reflectivity of point b using the dot reflectivity distribution data attached to dot B and the distance or coordinates from the center of dot A. I do. Thus, the reflectance at the point b is obtained by multiplying the two reflectances.

As described above, the reflectance distribution data of the output image can be obtained by sequentially calculating the reflectance at each point on the output image. At the time of this calculation, as described above, the calculated dot position is the center of the dot of the corresponding pixel,
In other words, it is treated as the center of the reflectance distribution. The reflectance distribution data thus obtained is output to an auxiliary storage device or the like, and a series of simulation processing ends.

The dot reflectance distribution data selected according to the state of the neighboring pixel data of the pixel is pasted to the dot position corresponding to the OFF pixel, and the reflectance at each point of the output image is calculated. At this time, ON / OFF of the pixel corresponding to the related dot position is checked. In this way, the dot reflectance distribution data at the dot position corresponding to the OFF pixel may be ignored. This is the same in the following embodiments.

When the reflectance of the recording paper cannot be approximated by 1 and 0, the reflectance at the peripheral portion of the dot reflectance distribution is 1.0 (1).
(00%) cannot be approximated. In this case, the reflectance distribution of the output image as described above is calculated using the dot reflectance distribution data normalized by dividing by the reflectance Rp of the recording paper itself, which is the maximum value of the dot reflectance distribution.

Thereafter, R is calculated for the entire calculated reflectance distribution.
The final reflectance distribution may be obtained by multiplying by p. This is the same in each embodiment. In addition, when a plurality of dots are overlapped and the reflectance is multiplied sequentially, for example, when the ratio of ON dots is high, the reflectance may become extremely small.

For example, in the case of a black solid image output example described later, for example, it is desirable to set the reflectance at the time of outputting a solid black image as a limiter so that the reflectance does not become smaller than this.

As described above, other than the reflectance, (optical) density, brightness, etc. can be used as the physical quantity of the output image, but the method of superimposing the physical quantity in the overlapping portion of the dots depends on the physical quantity used. It is necessary to set appropriately according to. Various image quality evaluation methods can be applied by using the reflectance distribution of the output image obtained as described above.

For example, since the image density can be obtained by taking the average value of the reflectance distribution, the gamma characteristic and the gradation density characteristic of the image recording apparatus can be evaluated. Also, the reflectance distribution is graphed, or converted into a luminance signal corresponding to the reflectance, and the CRT is displayed.
Displaying the image on a monitor or the like enables simple image evaluation. Further, by inputting the reflectance distribution data to an image quality evaluation device (or a program), a desired image quality evaluation amount can be calculated quantitatively.

For example, noise can be evaluated for an image by inputting reflectance distribution data to an image evaluation device as disclosed in Japanese Patent Application Laid-Open No. Hei 10-23191. Further, it is possible to obtain the reflectance distribution by inputting the data of the line pair image as the input image data, and obtain the MTF from the reflectance distribution.

The present invention can be applied to a case where input image data is multi-valued data expressing the size or density of a dot with, for example, 8 bits / pixel. For example, when calculating neighboring pixel data, each element of the mask is used. If it is set to 1/255, it can be applied as it is. Further, regarding the reflectance data of the target pixel, the dot intensity may be continuously changed according to the pixel data (0 to 255).

In the following description, the reflectance is used as the physical quantity of the output image finally obtained, but the distribution may be obtained by using any other physical quantity such as density and brightness. In that case, it will be used in the following description. "Reflectance" such as reflectance distribution, dot reflectance distribution data, dot reflectance distribution variation data, and reflectance distribution correction data may be read as "physical quantities" such as density and brightness to be used.

In this embodiment, it goes without saying that the present invention may be implemented by dedicated hardware, but may be implemented by software using a general computer. When implemented in software, a program for the image simulation method of the present invention is read directly from a recording medium, such as a magnetic disk, an optical disk, a magneto-optical disk, or a memory card, on which the program is recorded into a main memory of a computer. To be executed by the CPU.

Alternatively, in an auxiliary storage device such as a hard disk, the image simulation method of the present embodiment is implemented by temporarily storing the data, reading it into the main memory when necessary, and executing the program by the CPU. It is also possible to implement the program in a computer as a ROM storing the program.

In a system in which a plurality of computers are connected by a LAN or a WAN, a processing form in which a certain local computer loads the same program from another computer and executes the processing, or stores the same program. The computer is provided with necessary data from a local computer to execute processing.

The result can be processed by a local computer. Data necessary for starting the processing is input from, for example, a recording medium, from an input device such as an image scanner, or from an external device via a network or the like. A storage area for data necessary for starting such processing and intermediate data for processing is statically or dynamically allocated, for example, on a main memory of a computer.

The final processing result is passed, for example, to another application program running on a computer, written to an auxiliary storage device such as a hard disk or a recording medium such as a floppy (registered trademark) disk, or The data is output to an external device via a network or the like.

According to the first embodiment of the present invention described above, it is possible to easily evaluate the qualitative and quantitative effects of the dot fluctuation on the output image.

(Operation of Image Simulation System)

The operation of the image simulation system according to the first embodiment of the present invention will be described in further detail. Less than,
The operation of the first embodiment will be described, but it can be implemented on a general computer.

In the first embodiment of the present invention, an image recording apparatus (hereinafter, referred to as a target apparatus for simulation) is used.
The purpose of this is to obtain the reflectance distribution (or other specific physical quantity distribution) of an image that would be output when certain image data is input to an image recording apparatus. First, there is image data (input image data).

Further, recording density data and basic reflectance distribution data, which are basic specification data of the image recording apparatus, are also input. However, when calculating the reflectance distribution of an output image with respect to certain image data, if the previously input recording density data and basic reflectance distribution data can be used as they are, only image data needs to be input.

Conversely, when it is desired to simulate an output image by changing the recording density data and / or the dot reflectance distribution data using the same image data,
There is no need to input image data again.

In FIG. 1, input image data is input from the image input means 101. In the input image data, dots are ON when the target device is a binary image recording device.
A 1-bit / pixel data string representing "0" and "1" as to whether the dot is OFF or an 8-bit / pixel data string as "0" and "255" to indicate whether the dot is ON or OFF.

In the case of a multi-valued image recording apparatus, the size or density of a dot is determined by a plurality of bits (usually 8 bits).
/ Pixel). The recording density data is a unit data of the resolution of the image recording apparatus, generally in dpi (dotperinch).

When simulating the output image of an image recording apparatus for forming a color image, data of each component of the color image is input as input image data (if necessary, the dot reflectance distribution data is also used for each component). Prepared separately). In the following description, unless otherwise specified, input image data is binary image data representing whether a dot is ON or OFF by “0” and “1”.

The basic reflectance distribution data shown in FIG. 2 is prepared in advance based on the measurement result of the output image, or based on prediction / estimation, and is used when calculating the reflectance distribution of one dot. It is. Basic dot reflectivity distribution data is actually a function (for example, f (r) or f (x, y) form) using the distance from the center of the dot or the xy coordinate as a variable, or a two-dimensional LUT ( Lookup table).

When necessary data is input, thereafter, a repetitive process for each pixel of the input image data is started (FIG. 1). In addition, as described later, some input data may be present in some cases, and these may be added as necessary. First, one pixel in the input image data is selected as a target pixel, and it is determined whether the target pixel is ON “1”. This determination is made by, for example, the reflectance distribution calculating means 106 in FIG. Attention pixel is OFF
If "0", the pixel is ignored and the process returns to the target pixel selection step, where the next target pixel is selected.

If the target pixel is ON, pixel data near the target pixel is detected from the input image data. The detection of the neighboring pixel data is performed by the neighboring pixel data detecting unit. The neighboring pixel data indicates the state of the pixel data in the vicinity of the target pixel. For example, in the simplest case, one of the upper, lower, left, and right neighboring pixel data of the target pixel is 1 when all the neighboring pixel data are on. Are output as 0 when off.

The dot position of the target pixel is determined by the position of the target pixel relative to the basic dot position at which dots are to be printed based on the recording density data (disposed at equal pitches in both x and y directions at the reciprocal pitch of the recording density). Is calculated by adding a predetermined variation amount based on the state of the neighboring pixel data. The calculation of the dot position is performed by the dot position calculation means 105 in FIG.

Next, the dot reflectivity distribution data of the target pixel, that is, the data representing the reflectivity distribution of the dot recorded corresponding to the target pixel is compared with the basic reflectivity distribution data by the neighboring pixel data of each pixel. Is calculated by adding a predetermined amount of variation based on.

The data of the reflectance distribution 113 of the dot is pasted at the dot position corresponding to the pixel of interest. That is, the dot reflectance distribution data is stored in association with the dot position. In FIG. 1, the calculation of the dot reflectance distribution data is performed by the dot reflectance distribution data calculating means 104, and the sticking of the target pixel to the dot position is performed by the reflectance distribution calculating means 106.

The addition of the amount of variation based on the neighboring pixel data in the step of calculating the dot position and dot reflectance data is performed as necessary, and can be omitted in one or both steps. is there. In addition, it should be set according to the purpose of the simulation or according to the characteristics of the image recording apparatus.

Further, the detection of the neighboring pixel data, the calculation of the dot reflectance distribution data based on the state of the neighboring pixel data, and the calculation of the dot position are performed regardless of whether the target pixel is ON or OFF. Calculation means 10
In 6, the calculated dot reflectance distribution data may be attached to the corresponding dot position only when the target pixel is ON. This is the same in each embodiment.

The calculation of the neighboring pixel data is performed by the method described above.
Alternatively, more generally, pixel data (0 or 1) of about one to several tens of pixels around the target pixel is detected, and a weight corresponding to the distance from the target pixel, for example, the k-th power of the distance from the target pixel is detected. It is obtained by multiplying by a weight of (k> 1) and adding.

FIG. 3 is an explanatory diagram schematically showing an example of a specific calculation method. The basic position fluctuation amount is one of basic data of the dot position fluctuation amount 303 based on a measurement result of an output image and prediction / estimation, or one of input data that can be arbitrarily input.

Here, the basic position variation is, for example, the standard deviation of the dot position variation in the x and y directions.
The basic position fluctuation amount is calculated by the dot position calculation unit 301 based on the neighboring pixel data of each pixel. That is, after being multiplied by the normal random number 304, the dot position 310 of each dot is calculated by being added to the basic dot position 302 of each dot calculated from the recording density data as a variation in the adder 306.

By multiplying the standard deviation of the dot position variation by the normal random number 304, the dot position variation can be reproduced well when the spatial frequency dependence of the dot position variation is low. In the dot position calculation unit 301,
The correction based on the neighboring pixel data is performed according to the characteristics of the image recording apparatus.

For example, in an output device in which the position fluctuation of one isolated dot is larger than that in other image patterns, the neighboring pixel data is set so that the dot position fluctuation amount becomes relatively large for the pixel having small neighboring pixel data. For pixels with large data, correction is made so that the dot position fluctuation amount becomes small. The dot position variation can be given as a spatial frequency characteristic of the dot position variation.

FIG. 4 shows an example of such a spatial frequency characteristic. Examples of this include periodic dot position fluctuations due to recording paper feed errors, random high frequency dot position fluctuations due to component processing errors in the image recording device, and low frequency fluctuations associated with recording media (such as photoconductors in electrophotography). It contains various spatial frequency components such as dot position fluctuations.

FIG. 5 is a diagram showing an example of the internal configuration of the dot position calculating means in FIG. As shown in FIG. 4, the dot position calculating means 5 when the spatial frequency characteristic of the dot position change is given as the basic dot position change data
00.

The basic dot position is calculated based on the recording density data. On the other hand, white noise generating means 503
To generate white noise, which is
To perform a fast Fourier transform (FFT) to convert to a spatial frequency space.

This converted data is supplied to the inverse FFT processing means 50.
6. Perform an inverse FFT treatment according to 6. As a result, noise having the desired spatial frequency characteristic, that is, a dot position variation amount is generated. The dot position variation is corrected by the dot position calculator 500 based on the neighboring pixel data, and is added to the basic dot position by the adder 508. In this way, the dot position 510 to which the position variation according to the dot position variation data (spatial frequency characteristic) is added is obtained, and this is given to the reflectance distribution calculating means 106 in FIG.

FIG. 6 is a diagram showing a variation amount according to the characteristics of the image recording apparatus. This is a variation amount according to the characteristics of the image recording apparatus. In calculating the dot reflectance distribution, at least one of the intensity and size of the basic reflectance distribution data is added to the basic pixel distribution data by a variation amount according to the characteristics of the image recording apparatus based on the neighboring pixel data.

FIG. 7 is a diagram showing a variation amount according to the characteristics of the image recording apparatus. This is a variation amount according to the characteristics of the image recording apparatus. In calculating the dot reflectance distribution, at least one of the intensity and size of the basic reflectance distribution data is added to the basic pixel distribution data by a variation amount according to the characteristics of the image recording apparatus based on the neighboring pixel data. As described above, the dot reflectance distribution data to be applied to the target pixel can be calculated.

FIG. 8 is an explanatory diagram schematically showing an example of a specific calculation method. Here, the basic reflectance fluctuation data consisting of the basic fluctuation amount of the dot size and dot intensity. These can be input as the basic data of the fluctuation amount of the dot reflectance distribution based on the measurement results of the actual output image and the prediction / estimation. Input data.

Here, the dot size variation 801 and the dot intensity variation 802 are, for example, the standard deviation of the dot size variation and the standard deviation of the dot intensity variation, respectively, and the basic reflectance variation is the neighboring pixel of each pixel. Each is corrected based on the data.

After being multiplied by the normal random numbers 803 and 804, the reflectance distribution calculator 810 calculates the dot reflectance distribution data of each dot by adding the variation to the basic dot reflectance distribution data 807. .

As described above, the addition of these fluctuations is calculated by the calculation units 808 and 809. By multiplying the standard deviation of the reflectance distribution variation by the normal random numbers 803 and 804, the dot reflectance variation can be reproduced well when the spatial frequency dependence of the dot reflectance distribution variation is low.

Further, the variation of the dot reflectance distribution is corrected based on the neighboring pixel data in accordance with the characteristics of the image recording apparatus. In an output device that is larger than at the time of, the variation in dot reflectance distribution is relatively large for pixels with small neighboring pixel data,
Correction is performed so that the dot reflectance distribution fluctuation amount of pixels having large neighboring pixel data is small.

Conversely, for an output device in which isolated dots are hardly reproduced, correction is made so that the variation in dot reflectance distribution is reduced for pixels with small neighboring pixel data.

FIG. 9 is a diagram schematically showing a simulation result for certain input image data. FIG. 3 schematically shows a simulation result for certain input image data, that is, a reflectance distribution of an output image, as a grayscale image. In FIG. 9, the regularly arranged black dots are
The basic dot position where the dot calculated based on the recording density data should be recorded

The basic dot position is when a dot is recorded at the dot position of each dot to which a predetermined amount of variation has been added, and the pixel corresponding to that dot position is ON. As described above, the reflectance distribution data calculated based on the state of the neighboring pixel data of the corresponding pixel is attached to the dot position.

The reflectance distribution calculation means 106 in FIG. 1 calculates the reflectance at each point at a pitch finer than the recording density, which is schematically shown by a broken line in FIG. For example, when determining the reflectance of the point a, the calculation is performed based on the distance or coordinates from the center of the closer dot A and the dot reflectance distribution data attached to the dot position.

When the dot reflectance distribution data is given by the above function, the reflectance is calculated by substituting the center or the calculated distance or coordinates of the dot A from the dot position into the function. .

At points such as point b which are affected by dots A and B, generally a plurality of dots, the dot reflectance distribution data affixed to dot A and the center of dot A Calculates the reflectivity of point b using the distance or coordinates of point b, and calculates the reflectivity of point b using the dot reflectivity distribution data attached to dot B and the distance or coordinates from the center of dot A. I do. Thus, the reflectance at the point b is obtained by multiplying the two reflectances.

As described above, the reflectance distribution data of the output image can be obtained by sequentially calculating the reflectance at each point on the output image. At the time of this calculation, as described above, the calculated dot position is the center of the dot of the corresponding pixel,
In other words, it is treated as the center of the reflectance distribution. The reflectance distribution data thus obtained is output to an auxiliary storage device or the like, and a series of simulation processing ends.

At the dot position corresponding to the OFF pixel, the dot reflectance distribution data selected according to the state of the neighboring pixel data of the pixel is pasted, and the reflectance at each point of the output image is calculated. At this time, ON / OFF of the pixel corresponding to the related dot position is checked. In this way, the dot reflectance distribution data at the dot position corresponding to the OFF pixel may be ignored. This is the same in each embodiment described later.

If the reflectance of the recording paper cannot be approximated by 1.0, the reflectance at the peripheral portion of the dot reflectance distribution is 1.0 (1).
(00%) cannot be approximated. In this case, the reflectance distribution of the output image is calculated using the dot reflectance distribution data normalized by dividing by the maximum value (reflectance of the recording paper itself) Rp of the dot reflectance distribution.

Thereafter, R is calculated for the entire calculated reflectance distribution.
The final reflectance distribution may be obtained by multiplying by p. This is the same in each embodiment. Also ON
For example, when the ratio of the dots is high and a plurality of dots are overlapped and the reflectance is sequentially multiplied, the reflectance may become extremely small. In such a case, for example, it is desirable to set the reflectivity at the time of outputting a solid black image as a limiter so that the reflectivity does not become smaller than this.

As described above, the (optical) density and lightness other than the reflectance can be used as the physical quantity of the output image, but the method of superimposing the physical quantity in the overlapping portion of the dots depends on the physical quantity used. It is necessary to set appropriately according to. Various image quality evaluation methods can be applied by using the reflectance distribution of the output image obtained as described above.

For example, since the image density can be obtained by taking the average value of the reflectance distribution, it is possible to evaluate the gamma characteristic and the gradation density characteristic of the image recording apparatus. Also, the reflectance distribution is graphed, or converted into a luminance signal corresponding to the reflectance, and the CRT is displayed.
Displaying the image on a monitor or the like enables simple image evaluation. Further, by inputting the reflectance distribution data to an image quality evaluation device (or a program), a desired image quality evaluation amount can be calculated quantitatively.

For example, noise of an image is evaluated by inputting reflectance distribution data to an image evaluation device as disclosed in Japanese Patent Application Laid-Open No. Hei 10-23191.
Further, as input image data, data of a line pair image is input to obtain a reflectance distribution, and MT is calculated from the reflectance distribution.
F can be obtained.

The present invention can be applied to a case where input image data is multi-valued data expressing dot size or density with, for example, 8 bits / pixel. For example, when calculating neighboring pixel data, each element of the mask If it is set to 1/255, it can be applied as it is. Further, regarding the reflectance data of the target pixel, the dot intensity may be continuously changed according to the pixel data (0 to 255).

(Operation of Image Simulation Apparatus) The operation of the image simulation apparatus according to Embodiment 1 of the present invention is shown in FIGS.

First, in step S1010, data is input. Next, in step S1011, a target pixel is selected. When the process proceeds to step S1011 and a target pixel is selected, a dot position is calculated in step S1013. Next, step S1014
In, dot reflectance distribution data is calculated.

Next, in step S1015,
It is determined whether or not the pixel is the last pixel. If the pixel is the last pixel, the process proceeds to step S1016, where the reflectance distribution is calculated, the reflectance variation is added in step S1017, the result is output in step S1018, and the above process ends (END).

If it is not the pixel of interest in step S1012, and if it is not the last pixel in step S1015, the process returns to step 1011 again to perform the processing so far.

The operation of the image simulation system according to the first embodiment of the present invention will be described in more detail. Hereinafter, the operation of the first embodiment will be described with reference to FIG. 1, but the operation can be performed on a general computer.

According to the first embodiment of the present invention, an image recording apparatus (hereinafter simply referred to as an image recording apparatus) which is a target apparatus for simulation receives an image which is to be output when certain image data is input. FIG. 7 is a diagram schematically illustrating a simulation result for input image data for the purpose of obtaining a reflectance distribution (or a distribution of another specific physical quantity). The data input here includes image data (input image data) first.

Further, recording density data and basic reflectance distribution data, which are basic specification data of the image recording apparatus, are also input. However, when calculating the reflectance distribution of an output image with respect to certain image data, if the previously input recording density data and basic reflectance distribution data can be used as they are, only image data needs to be input.

Conversely, when it is desired to simulate the output image by changing the recording density data and / or the dot reflectance distribution data using the same image data,
There is no need to input image data again.

According to the first embodiment of the present invention described above, it is possible to easily evaluate the qualitative and quantitative effects on the output image due to dot fluctuation.

(Embodiment 2) An example of a simplified block configuration of an image simulation apparatus according to Embodiment 2 of the present invention will be described. FIG. 11 shows Embodiment 2 of the present invention.
1 is a block diagram illustrating a configuration of an image simulation apparatus according to the first embodiment. Note that, for the same configuration as that of the first embodiment in FIG.

As is apparent from a comparison between FIG. 11 and FIG. 1, a reflectance distribution correcting means 1100 is added to the output side of the reflectance variation adding means 112. The point where correction data is input,
Response function 1 is stored in the reflectance distribution correction data storage unit 1101,
The second embodiment is different from the first embodiment in that blurring due to transfer and crushing due to fixing can be corrected. Different components will be described, and the same components will be denoted by the same reference numerals and detailed description thereof will be omitted.

Also, the reflectance distribution correction data storage means 11
01 enables correction of blurring due to transfer of the response functions 1 and 2 and crushing due to fixing, and sends these correction data to the reflectance distribution correction unit 1100 to obtain the reflectance distribution 113.

For example, in an image recording apparatus such as an electrophotographic image recording apparatus which forms an image by a plurality of steps such as development, transfer and fixing, the image quality deteriorates in each step. Further, the influence of the optical dot gain that blurs the image recorded on the paper due to the scattering of light inside the recording paper may not be ignored. It is possible to obtain a reflectance distribution of an output image reflecting the influence of deterioration due to such various factors. In the present embodiment, the reflectance distribution data output from the reflectance distribution calculation of the reflectance distribution correction unit 1100 can be corrected according to the reflectance distribution correction data.

The reflectance distribution correction data represents deterioration characteristics and the like in processes such as development, transfer, and fixing. Specifically, for example, the reflectance distribution correction data is in the form of a response function or a spatial frequency characteristic corresponding to the deterioration characteristics. Can be given. As an example, as shown in FIG. 11, a response function 1 corresponding to the deterioration (blurring) characteristic of the transfer process and a response function 2 corresponding to the deterioration (crushing) characteristic of the fixing process are given as the reflectance distribution correction data. Can be

In this case, the reflectance distribution correcting means 1100
Performs a convolution operation on the reflectance distribution (corresponding to the reflectance distribution after the development process) data calculated by the reflectance distribution calculating means 106 using the response function 1, and applies the response function 2 Performs a convolution operation using. As a result, final reflectance distribution data is obtained in which the influence of blurring due to the transfer step and crushing due to the fixing step is added.

The reflectance distribution correction data may be provided with response functions corresponding to three or more deterioration characteristics due to different factors. Conversely, response functions representing two or more deterioration characteristics are converted into one response function. It may be given in a summarized form.

In the second embodiment, since the correction can be performed in consideration of the blur at the time of transfer and the crush at the time of fixing, the correction including the characteristics of the image recording apparatus can be performed, and the reliability and the like can be improved. Can be improved.

The processing flow of this embodiment is obtained by adding a correction processing step by the reflectance distribution correction means 1100 between the step of calculating the reflectance distribution and the step of outputting the result in the processing flow shown in FIG. . The data input in the data input step of the processing flow also includes the reflectance distribution correction data.

FIG. 12 is a diagram showing the internal structure of the reflectance distribution correcting means in FIG. As described above, the spatial frequency characteristic according to the deterioration characteristic may be given as the reflectance distribution correction data. Reflectance distribution correction means 120 in this case
In an example of the internal configuration of 0 (1100) (contents of the correction processing), as the reflectance distribution correction data, a spatial frequency characteristic 11203 representing the degradation characteristic of the transfer process and a spatial frequency characteristic 21204 representing the degradation characteristic of the fixing process are given. .

In the reflectance distribution correcting means 1200,
The reflectance distribution data generated by the reflectance distribution calculation means 106 is converted by the FFT 1201, the converted data is multiplied by the spatial frequency characteristic 1203, and the result is multiplied by the spatial frequency characteristic 1204 by the multiplication means.

As described above, the reflection distribution is corrected in accordance with the deterioration characteristic, and the corrected result is subjected to the inverse Fourier transform by the inverse FFT 1202 to obtain the final reflectance distribution data reflecting the deterioration due to the transfer step and the fixing step. Can be obtained.

Also in this case, three or more spatial frequency characteristics may be given as the reflectance distribution correction data, and these may be sequentially multiplied by the reflectance distribution converted to the spatial frequency space. It is also possible to give one or more spatial frequency characteristics in one form.

In the above embodiment, the dot position of the target pixel and the variation of the dot reflectance distribution are variably added based on the state of the neighboring pixel data of the target pixel.

By doing so, it is possible to perform an image simulation capable of calculating a highly accurate reflectance distribution including the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation depending on the image data. Further, it is possible to easily perform high-precision prediction and evaluation of the output image quality using the calculated reflectance distribution without actually outputting the image.

(Modification 1 of Embodiment 2) FIG. 13 shows Modification 1 of the reflectance distribution variation adding section 1300. The arithmetic function for comparing and adding is B. Reflectance distribution calculator 1
The reflectance distribution data Rij 301 is compared by the reflectance distribution variation adding unit 1300 with Rij> R0.

The reflectance distribution variation adding section 1300 also
The reflectance variation data is multiplied by the normal random number, the result value is added to the comparison pass / fail data, and the reflectance distribution data with the variation added can be sent. Note that the comparison Rij
When the reflectance distribution data is smaller than the reference value R0 in> R0, the above processing is not performed in the first place. This makes it possible to increase the processing speed.

FIG. 14 is a characteristic diagram showing the relationship between the amplitude of the reflectance fluctuation and the spatial frequency in FIG. Looking at the characteristic from the peak value 1400 to the down value 1401 from this characteristic diagram, it can be seen that the variation in the amplitude of the reflectance variation gradually decreases as the spatial frequency increases.

(Modification 2 of Embodiment 2) FIG. 15 is a block diagram showing Modification 2 of Embodiment 2. 15, a reflectance distribution variation adding unit 1500 performs white noise 1502, an FFT 1503 that performs fast Fourier transform based on white noise, and a filtering of an FET output, in addition to the calculation function B for performing comparison and addition in FIG. It comprises a filtering unit 1504 and an inverse FFT 1505 for performing an inverse Fourier transform on the filtering output.

The filtering unit 1504 performs filtering output to the inverse FFT 1505 according to the FFT output and the reflectance variation data based on the frequency characteristics of the reflectance distribution of the recording paper. In this modified example, it is possible to perform correction in consideration of the frequency characteristic of the reflectance distribution of the recording paper.

[Third Embodiment] First, the configuration of an entire image simulation system including an image simulation device according to a third embodiment of the present invention will be described.

(Configuration of Image Simulation System)
FIG. 16 is a diagram illustrating a block configuration of an image simulation system device according to the third embodiment of the present invention.

First, differences from the configuration of the first embodiment will be described, and the same components will be denoted by the same reference numerals and detailed description thereof will be omitted. In the configuration of FIG. 16, the same parts as those of the first embodiment in FIG.
It is represented by

The difference is that the neighboring pixel data detecting unit 1600 is detected based on one output of the image input unit 101, and the basic dot reflectance distribution data is calculated by the dot reflectance distribution data calculating unit 104 according to the detection result. That is, the dot position variation data 110 is determined according to the detection result. Thus, the dot position can be calculated based on the data detected by the neighboring pixel data detection unit 1600.

FIG. 17 is a characteristic diagram showing the relationship between the reflectance and the distance from the dot center. It can be seen that the reflectance becomes closer to 0 as the point 1700 becomes closer to the distance of the dot center to 0.

FIG. 18 is a view for explaining a method of superimposing a target pixel of a mask and image data. In FIG. 18, a mask 1800 assigned to each pixel
And the pixel of interest 1801 of the image data are superimposed and 23
Image data 1802 composed of pixels corresponding to / 40 can be obtained.

FIG. 19 is a block diagram showing the structure of the dot position calculating means in FIG. The same parts as those in the configuration of the first embodiment are denoted by D. Dot position calculator 190
The position variation correction means 1902 of 0 calculates a correction value based on the basic position variation 1901 and the neighboring pixel data 1903. The multiplier 1905 calculates the correction value and the normal random number 190.
4 and a basic dot position value is added by an adder 508 to obtain a dot position.

FIG. 20 is a characteristic diagram showing the relationship between the spatial frequency and the amplitude of fluctuation. In FIG. 20, starting from a low-frequency fluctuation 2001, a periodic position fluctuation 2002 due to a paper feed speed fluctuation has a peak characteristic, and a random high-frequency fluctuation 2003 shows a drooping characteristic of a spatial frequency.

As described above, the reflectance is used as the physical quantity of the output image finally obtained, but the distribution may be obtained by using any other physical quantity such as density and brightness. In that case, the "reflectance" used in the following description, such as reflectance distribution, dot reflectance distribution data, dot reflectance distribution variation data, and reflectance distribution correction data, is used for density, brightness, etc. What is necessary is just to read "physical quantity".

FIG. 21 is a block diagram showing the configuration of the dot position calculation unit. The same parts as in the configuration of the first embodiment are denoted by E. The position variation correction means 2100 of the dot position calculation unit 2100 calculates a correction value based on the output of the inverse FFT 506 and the neighboring pixel data 2106. The result and the basic dot position value can be added by the adder 508 to determine the dot position.

FIG. 22 is a diagram showing the amount of change according to the characteristics of the image recording apparatus. FIG. 22 shows the characteristics of the reflectance 2202 and the distance 2201 from the center of the dot, the variation 2203 in the characteristics and the basic reflectance distribution data 2204. This is a variation amount according to the characteristics of the image recording apparatus. In calculating the dot reflectance distribution, at least one of the intensity and size of the basic reflectance distribution data is added to the basic pixel distribution data by a variation amount according to the characteristics of the image recording apparatus based on the neighboring pixel data.

FIG. 23 is a diagram showing the amount of fluctuation according to the characteristics of the image recording apparatus. In FIG. 23, the characteristics are the reflectance 2302 and the distance 2301 from the dot center. The variation 2303 in the characteristics and the basic reflectance distribution data 2304 are shown. The dot reflectivity distribution calculation, which is a variation amount according to the characteristics of the image recording apparatus, determines at least one of the intensity and size of the basic reflectivity distribution data based on the neighboring pixel data according to the characteristics of the image recording apparatus. The amount of fluctuation.
As described above, the dot reflectance distribution data to be applied to the target pixel can be calculated.

FIG. 24 is an explanatory diagram schematically showing one example of a specific calculation method. The same components as those in FIG. 8 are denoted by F. 24 is different from FIG. 24 in that the correction units 2401 and 2402 correct the dot size variation 801 and the neighboring pixel data 2403.
The point is that the correction results of 1,402 and the normal random numbers 803, 804 are multiplied by multipliers 805, 806.

FIG. 25 is an explanatory diagram schematically showing an example of a specific calculation method. The same configuration as that of FIG. 8 is denoted by G. 25 is different from FIG. 25 in that the correction units 2501 and 2502 correct the dot size variation 801 and the neighboring pixel data 2503.
The point is that the correction results of 1,502 and the normal random numbers 803, 804 are multiplied by multipliers 805, 806.

FIG. 26 is a characteristic diagram showing the relationship between the reflectance and the adjacent pixel data 2601 in FIG. FIG. 26 shows a curve 2602 obtained by plotting the relationship between the reflectance 2600 and the neighboring pixel data.

FIG. 27 is a diagram schematically showing a simulation result for certain input image data. FIG. 3 schematically shows a simulation result for certain input image data, that is, a reflectance distribution of an output image, as a grayscale image. In FIG. 27, regularly arranged black points are basic dot positions at which dots calculated based on the recording density data are to be recorded. FIG. 27 shows a reflectance calculation pitch 2700 and a dot recording pitch 2701. In addition, dots A and B serving as targets are illustrated.

The basic dot position is when a dot is recorded at the dot position of each dot to which a predetermined amount of variation has been added, and the pixel corresponding to that dot position is ON. As described above, the reflectance distribution data calculated based on the state of the neighboring pixel data of the corresponding pixel is attached to the dot position.

FIG. 28 is a diagram showing the basic reflectance distribution data in FIG. The basic reflectance distribution data is prepared in advance based on a measurement result of an output image or based on prediction / estimation, and is used to calculate a reflectance 2800 of one dot and a distribution up to a distance 2801 from a dot center. Is the basic data.

The basic reflectance distribution data is actually obtained by, for example, a function (eg, f (r) or f (x, y)) using the distance 2801 from the dot center or the x, y coordinates as variables, or 2 Given in the form of a dimensional lookup. When the necessary data is input, a repetitive process for each pixel of the input image data described below starts thereafter. In addition, there are some input data as described below, which will be added as necessary.

FIG. 29 is a diagram showing an example of a solid black image output. In the case of such an output example 2900, for example, it is desirable to set the reflectivity at the time of outputting a solid black image as a limiter so that the reflectivity does not become smaller than this.

FIG. 30 is a block diagram illustrating a configuration of an image simulation apparatus according to a modification of the second embodiment of the present invention in FIG. The difference from the configuration in FIG. 12 is that a neighboring pixel data detection unit 3000 is provided.
Neighboring pixel data is detected based on the image from the image input unit 101, and is input to the dot position calculation unit 105 as dot reflectance distribution data calculation unit 104 and dot position variation data 110. Even in this case, an image simulation can be performed.

FIG. 31 is a diagram showing the internal structure of the reflectance distribution correcting means in FIG. As described above, the spatial frequency characteristic according to the deterioration characteristic may be given as the reflectance distribution correction data. Reflectance distribution correction means 310 in this case
In an example of the internal configuration of 0 (1200) (contents of the correction processing), a spatial frequency characteristic 13103 representing the deterioration characteristic of the transfer process and a spatial frequency characteristic 23104 representing the deterioration characteristic of the fixing process are given as the reflectance distribution correction data. .

In the reflectance distribution correcting means 3100,
The reflectance distribution data generated by the reflectance distribution calculating means 106 is converted by the FFT 3101, the converted data is multiplied by the spatial frequency characteristic 31031, and the result is multiplied by the spatial frequency characteristic 23104 by the multiplying means.

As described above, the reflection distribution is corrected according to the deterioration characteristics, and the corrected result is subjected to the inverse fast Fourier transform by the inverse FFT 3102 to obtain the final reflectance distribution data reflecting the deterioration due to the transfer step and the fixing step. Can be obtained.

FIG. 32 is a flowchart for explaining the operation in the third embodiment. Steps that perform the same processing as the steps in FIG. 11 are denoted by the same step names, and detailed description is omitted. In FIG. 32, step S320
If it is 0, the neighborhood data is detected when the pixel is the target pixel, and the dot position is calculated in step S3201. Then
In step S3202, a dot reflection position is obtained,
In step S3203, the dot reflection position is pasted. Next, in step S3204, it is determined whether or not the pixel is the last pixel. If it is the last pixel, the reflectance distribution is calculated in step S1016. If it is not the last pixel, the process returns to step S1011 again.

In the embodiments and the modifications described above, the reflectivity distribution of the image output from the image recording apparatus is determined based on the output image quality, including the characteristics of the image recording apparatus such as differences in the amount of dot variation due to image data. Enables highly accurate prediction and evaluation, and enables evaluation in a short time.

[0230]

As described above, according to the first aspect of the present invention, input image data is recorded, and when simulating recording output, pixel data near the target pixel is detected from the input image data. Calculating the dot position of the pixel of interest based on the detected pixel data; calculating distribution data from the pixel data of the detected pixel of interest; calculating the calculated dot position of each pixel and the calculated distribution of each pixel; The reflectance distribution data of the image expected based on the data is calculated, and the reflectance distribution of the image output from the image recording device is converted into the output image including the characteristics of the image recording device such as a difference in the amount of dot variation due to the image data. This makes it possible to perform high-precision prediction and evaluation of quality, and to enable an evaluation in a short time.

According to the second aspect of the present invention, the predetermined fluctuation with respect to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the detected neighboring pixel data of the target pixel. The dot position of the pixel of interest is calculated by adding the amount, and the reflectance distribution of the image output from the image recording apparatus is adjusted to include the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data. There is an effect that an image simulation apparatus that enables accurate prediction and evaluation and enables evaluation in a short time is obtained.

According to the third aspect of the present invention, a predetermined amount of variation is added to the basic reflectance distribution data based on the detected state of the neighboring pixel data of the target pixel, and the dot reflectance distribution for the target pixel is obtained. Data is calculated, and the reflectance distribution of the image output from the image recording device is accurately predicted and evaluated for the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data, There is an effect that an image simulation apparatus capable of performing evaluation in a short time can be obtained.

According to the invention described in claim 4, based on the calculated dot position of each pixel and the dot reflectance distribution data of each pixel calculated by the distribution data calculating means, the input image data is Calculating the reflectance distribution of the image expected to be output from the recording means, and calculating the reflectance distribution of the image output from the image recording device by using the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. This makes it possible to obtain an image simulation apparatus that enables highly accurate prediction and evaluation of output image quality, and enables evaluation in a short time.

According to the invention described in claim 5, the calculated reflectance distribution is corrected according to one or more deterioration characteristics related to image formation of the recording means, and the image output from the image recording apparatus is corrected. It is possible to accurately predict and evaluate the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot fluctuation due to the image data, and to evaluate the reflectance distribution in a short time. There is an effect that an image simulation device can be obtained.

According to the invention of claim 6, when input image data is recorded and a recording output is simulated, pixel data near the target pixel is detected from the input image data and detected. A dot position of a target pixel is calculated based on the pixel data, and a distribution of a specific physical quantity of an image recorded and output based on a specific physical quantity such as density, brightness, and luminance is obtained from the detected pixel data of the target pixel. In addition, the reflectance distribution of the image output from the image recording device can be accurately predicted and evaluated for the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data, and can be performed in a short time. This produces an effect that an image simulation device capable of evaluating the above is obtained.

According to the seventh aspect of the present invention, the predetermined variation with respect to the basic dot position calculated from the recording density data corresponding to the recording density based on the detected state of the neighboring pixel data of the target pixel. The dot position of the pixel of interest is calculated by adding the amount, and the reflectance distribution of the image output from the image recording apparatus is adjusted to include the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data. An effect is obtained that an image simulation apparatus that enables accurate prediction and evaluation and can perform evaluation in a short time is obtained.

Further, according to the present invention, when recording the input image data and simulating the recording output, the dot position of the target pixel is calculated from the input image data, and the dot reflectance of the target pixel is calculated. The distribution data is calculated, and the detected dot position of each pixel and the reflectance of the image recorded and output with respect to the input image data using the dot reflectance distribution data of each pixel calculated by the reflectance distribution data calculation means. Calculate the distribution, add the reflectance variation data according to the characteristics of the image output target to the calculated reflectance distribution of the image, and change the reflectance distribution of the image output from the image recording apparatus by the dot variation due to the image data. An image simulation device that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device such as differences in the amount, and enables evaluation in a short time. An effect that is obtained.

According to the ninth aspect of the present invention, in the position calculation, the recording density data corresponding to the recording density, the dot position variation data, and the dot position of each pixel are calculated.
Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation depending on the image data, and evaluates the reflectance distribution of the image output from the image recording device in a short time This provides an effect that an image simulation device capable of performing the above operation is obtained.

According to the tenth aspect of the present invention,
In calculating the reflectance distribution data, the dot reflectance distribution data of each pixel is calculated from the basic dot reflectance data and the dot reflectance variation data, and the reflectance distribution of the image output from the image recording apparatus is represented by a dot based on the image data. It is possible to obtain an image simulation apparatus that enables highly accurate prediction and evaluation of the output image quality, including characteristics of the image recording apparatus such as a difference in the amount of fluctuation, and that can perform evaluation in a short time.

According to the eleventh aspect of the present invention, the reflectance distribution calculated by adding the reflectance variation data is corrected according to one or more deterioration characteristics related to image formation of the recording means, and the image recording apparatus To enable highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to image data, and to evaluate the reflectance distribution of the image output from the printer in a short time. There is an effect that an image simulation device capable of performing the above is obtained.

According to the twelfth aspect of the present invention,
When recording the input image data and simulating the recording output, pixel data near the pixel of interest is detected from the input image data, and the dot position of the pixel of interest is calculated based on the detected pixel data. From the pixel data of the pixel of interest, density, brightness, to obtain the distribution of the specific physical quantity of the image recorded and output based on a specific physical quantity such as luminance, the reflectance distribution of the image output from the image recording device It is possible to obtain an image simulation device that enables highly accurate prediction and evaluation of output image quality, including characteristics of an image recording device such as differences in dot fluctuation amount due to image data, and that can perform evaluation in a short time. It works.

According to the thirteenth aspect of the present invention,
When recording the input image data and simulating the recording output, pixel data near the pixel of interest is detected from the input image data, and the dot position of the pixel of interest is calculated based on the detected pixel data. The distribution data is calculated from the pixel data of the target pixel, and the expected image reflectance distribution data is calculated based on the dot position of each pixel calculated by the position calculation and the distribution data of each pixel calculated by the distribution data. Then, the reflectance distribution of the image output from the image recording apparatus can be accurately predicted and evaluated for the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot variation due to the image data, and can be performed in a short time. There is an effect that an image simulation method capable of evaluating the above is obtained.

According to the fourteenth aspect of the present invention,
Based on the state of the neighboring pixel data of the detected pixel of interest, a predetermined amount of variation is added to the basic dot position calculated from the recording density data corresponding to the recording density to calculate the dot position of the pixel of interest, and the distribution data The calculating step calculates dot reflectance distribution data for the pixel of interest by adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the detected neighboring pixel data of the pixel of interest, and the reflectance distribution calculating step includes: Based on the calculated dot position of each pixel and the calculated dot reflectance distribution data of each pixel, calculate the reflectance distribution of the image that is expected to be recorded and output with respect to the input image data, and output the image from the image recording device. The image recording device is capable of accurately predicting and evaluating the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. To enable highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to image data, and to evaluate the reflectance distribution of the image output from the printer in a short time. There is an effect that an image simulation method capable of performing the above is obtained.

According to the fifteenth aspect of the present invention,
In the reflectivity distribution calculating step, the calculated reflectivity distribution is corrected according to one or more deterioration characteristics related to image formation in the recording step, and the reflectivity distribution of an image output from the image recording apparatus is converted into a dot by image data. It is possible to obtain an image simulation method that enables highly accurate prediction and evaluation of the output image quality including characteristics of the image recording apparatus such as a difference in the amount of fluctuation, and enables an evaluation in a short time.

According to the sixteenth aspect of the present invention,
When the input image data is recorded, when simulating the recording output, pixel data near the target pixel is detected from the input image data, and the dot position of the target pixel is calculated based on the detected pixel data. From the pixel data of the pixel of interest, the density, brightness, luminance, and the like, the specific physical quantity distribution of the image recorded and output based on the specific physical quantity is obtained, and the reflectance distribution of the image output from the image recording apparatus is obtained. The effect is that an image simulation method that enables highly accurate prediction and evaluation of output image quality, including characteristics of the image recording apparatus such as differences in dot fluctuation amount due to data, and enables evaluation in a short time is obtained. To play.

According to the seventeenth aspect of the present invention,
A predetermined amount of variation is added to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the detected neighboring pixel data of the target pixel to calculate the dot position of the target pixel, and image recording is performed. Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to image data, and evaluates the reflectance distribution of the image output from the device in a short time. There is an effect that an image simulation method capable of performing the above is obtained.

According to the eighteenth aspect of the present invention,
A recording step of recording the input image data, a position calculating step of calculating the dot position of the pixel of interest from the input image data when simulating the recording output of the recording step, and a reflection of calculating the dot reflectance distribution data of the pixel of interest. Rate distribution data calculation step, using the dot position of each pixel detected in the detection step, and the dot reflectance distribution data of each pixel calculated in the reflectance distribution data calculation step, the input image data from the recording step A reflectance distribution calculating step of calculating the reflectance distribution of the output image; and adding reflectance variation data corresponding to the characteristics of the image output target to the reflectance distribution of the image calculated in the reflectance distribution calculating step. ,
Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation depending on the image data, and evaluates the reflectance distribution of the image output from the image recording device in a short time This provides an effect of obtaining an image simulation method capable of performing the following.

According to the nineteenth aspect,
In the position calculation, the recording density data corresponding to the recording density, the variation data of the dot position, and the dot position of each pixel are calculated, and in the reflectance distribution data calculation, the basic dot reflectance data, Dot reflectivity distribution data is calculated, the reflectivity distribution calculated in the reflectivity variation data adding step is corrected according to one or more deterioration characteristics related to image formation in the recording step, and the image output from the image recording apparatus is corrected. An image simulation method that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as the difference in the amount of dot variation due to the image data, and enables the evaluation in a short time. Is obtained.

According to the twentieth aspect of the present invention,
When simulating the recording output of the recording process, pixel data near the target pixel is detected from the input image data, and the dot position of the target pixel is calculated based on the detected pixel data. From the pixel data, density, brightness, luminance, and the like, to obtain a distribution of the specific physical quantity of the image output from the recording process based on the specific physical quantity, the reflectance distribution of the image output from the image recording apparatus image data The effect of this method is that an image simulation method that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to Play.

According to the twenty-first aspect of the present invention,
When recording the input image data and simulating the recording output, pixel data near the pixel of interest is detected from the input image data, and the dot position of the pixel of interest is calculated based on the detected pixel data. The distribution data is calculated from the pixel data of the target pixel, and the expected image reflectance distribution data is calculated based on the dot position of each pixel calculated by the position calculation and the distribution data of each pixel calculated by the distribution data. Then, the reflectance distribution of the image output from the image recording apparatus can be accurately predicted and evaluated for the output image quality, including the characteristics of the image recording apparatus such as the difference in the amount of dot variation due to the image data, and can be performed in a short time. This produces an effect of obtaining an image simulation program capable of evaluating the above.

According to the twenty-second aspect of the present invention,
Based on the state of the neighboring pixel data of the detected pixel of interest, a predetermined amount of variation is added to the basic dot position calculated from the recording density data corresponding to the recording density to calculate the dot position of the pixel of interest, and the distribution data The calculating step calculates dot reflectance distribution data for the pixel of interest by adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the detected neighboring pixel data of the pixel of interest, and the reflectance distribution calculating step includes: Based on the calculated dot position of each pixel and the calculated dot reflectance distribution data of each pixel, calculate the reflectance distribution of the image that is expected to be recorded and output with respect to the input image data, and output the image from the image recording device. The image recording device is capable of accurately predicting and evaluating the output image quality, including the characteristics of the image recording device such as the difference in the amount of dot variation due to the image data. To enable highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to image data, and to evaluate the reflectance distribution of the image output from the printer in a short time. There is an effect that an image simulation program capable of performing the above is obtained.

According to the twenty-third aspect of the present invention,
In the reflectivity distribution calculating step, the calculated reflectivity distribution is corrected according to one or more deterioration characteristics related to image formation in the recording step, and the reflectivity distribution of an image output from the image recording apparatus is converted into a dot by image data. It is possible to obtain an image simulation program that enables highly accurate prediction and evaluation of the output image quality, including characteristics of the image recording apparatus such as a difference in the amount of fluctuation, and enables an evaluation in a short time.

According to the twenty-fourth aspect of the present invention,
When the input image data is recorded, when simulating the recording output, pixel data near the target pixel is detected from the input image data, and the dot position of the target pixel is calculated based on the detected pixel data. From the pixel data of the pixel of interest, the density, brightness, luminance, and the like, the specific physical quantity distribution of the image recorded and output based on the specific physical quantity is obtained, and the reflectance distribution of the image output from the image recording apparatus is obtained. The effect of obtaining an image simulation program that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot variation due to data, and that enables evaluation in a short time. To play.

According to the twenty-fifth aspect of the present invention,
A predetermined amount of variation is added to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the detected neighboring pixel data of the target pixel to calculate the dot position of the target pixel, and image recording is performed. Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to image data, and evaluates the reflectance distribution of the image output from the device in a short time. There is an effect that an image simulation program capable of performing the above is obtained.

According to the twenty-sixth aspect of the present invention,
A recording step of recording the input image data, a position calculating step of calculating the dot position of the pixel of interest from the input image data when simulating the recording output of the recording step, and a reflection of calculating the dot reflectance distribution data of the pixel of interest. Rate distribution data calculation step, using the dot position of each pixel detected in the detection step, and the dot reflectance distribution data of each pixel calculated in the reflectance distribution data calculation step, the input image data from the recording step A reflectance distribution calculating step of calculating the reflectance distribution of the output image; and adding reflectance variation data corresponding to the characteristics of the image output target to the reflectance distribution of the image calculated in the reflectance distribution calculating step. ,
Enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation depending on the image data, and evaluates the reflectance distribution of the image output from the image recording device in a short time This provides an effect of obtaining an image simulation program capable of performing the following.

According to the twenty-seventh aspect of the present invention,
In the position calculation, the recording density data corresponding to the recording density, the variation data of the dot position, and the dot position of each pixel are calculated, and in the reflectance distribution data calculation, the basic dot reflectance data and the dot reflectance variation data are used to calculate each pixel. Dot reflectivity distribution data is calculated, the reflectivity distribution calculated in the reflectivity variation data adding step is corrected according to one or more deterioration characteristics related to image formation in the recording step, and the image output from the image recording apparatus is corrected. An image simulation program that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation depending on the image data, and enables quick evaluation. Is obtained.

According to the twenty-eighth aspect of the present invention,
When simulating the recording output of the recording process, pixel data near the target pixel is detected from the input image data, and the dot position of the target pixel is calculated based on the detected pixel data. From the pixel data, density, brightness, luminance, and the like, to obtain a distribution of the specific physical quantity of the image output from the recording process based on the specific physical quantity, the reflectance distribution of the image output from the image recording apparatus image data This makes it possible to obtain an image simulation program that enables highly accurate prediction and evaluation of the output image quality, including the characteristics of the image recording device, such as differences in the amount of dot fluctuation due to differences, and that enables evaluation in a short time. Play.

Further, according to the recording medium of the present invention, the reflectance distribution of the image output from the image recording apparatus includes the characteristics of the image recording apparatus such as the difference in the amount of dot fluctuation due to the image data. As a result, it is possible to perform highly accurate prediction and evaluation of the output image quality and to perform the evaluation in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a block configuration of an image simulation system according to a first embodiment of the present invention;

FIG. 2 is a diagram showing basic reflectance distribution data in FIG.

FIG. 3 is an explanatory diagram schematically showing an example of a specific calculation method.

FIG. 4 is a characteristic diagram illustrating a relationship between a spatial frequency and a fluctuation amplitude in the system in FIG. 1;

FIG. 5 is a diagram illustrating an example of an internal configuration of a dot position calculation unit in FIG. 1;

FIG. 6 is a diagram illustrating a variation amount according to characteristics of the image recording apparatus.

FIG. 7 is a diagram illustrating a variation amount according to characteristics of the image recording apparatus.

FIG. 8 is an explanatory diagram schematically showing an example of a specific calculation method.

FIG. 9 is a diagram schematically showing a simulation result for certain input image data.

FIG. 10 is an example of a processing flow of the image simulation apparatus according to the first embodiment of the present invention.

FIG. 11 is a block diagram illustrating a configuration of an image simulation apparatus according to a second embodiment of the present invention.

FIG. 12 is a diagram showing an internal configuration of a reflectance distribution correction unit in FIG. 11;

FIG. 13 is a diagram illustrating a first modification of the reflectance distribution variation adding unit;

FIG. 14 is a characteristic diagram showing a relationship between the amplitude of the reflectance fluctuation and the spatial frequency in FIG.

FIG. 15 is a block diagram showing a second modification of the second embodiment.

FIG. 16 is a diagram illustrating a block configuration of an image simulation system device according to a third embodiment of the present invention;

FIG. 17 is a characteristic diagram illustrating a relationship between a reflectance and a distance from a dot center.

FIG. 18 is a diagram illustrating a method of superimposing a target pixel of a mask and image data.

19 is a block diagram illustrating a configuration of a dot position calculation unit in FIG.

FIG. 20 is a characteristic diagram showing a relationship between a spatial frequency and a fluctuation amplitude.

21 is a block diagram illustrating a configuration of a dot position calculation unit in FIG.

FIG. 22 is a diagram illustrating a variation amount according to characteristics of the image recording apparatus.

FIG. 23 is a diagram illustrating a variation amount according to characteristics of the image recording apparatus.

FIG. 24 is an explanatory diagram schematically showing one example of a specific calculation method.

FIG. 25 is an explanatory diagram schematically showing an example of a specific calculation method.

FIG. 26 is a characteristic diagram showing a relationship between reflectance and adjacent pixel data in FIG.

FIG. 27 is a diagram schematically showing a simulation result for certain input image data.

FIG. 28 is a diagram showing basic reflectance distribution data in FIG. 16;

FIG. 29 is a diagram illustrating an example of a solid black image output.

FIG. 30 is a block diagram illustrating a configuration of an image simulation apparatus according to a modification of the second embodiment of the present invention in FIG. 12;

FIG. 31 is a diagram showing an internal configuration of a reflectance distribution correction unit in FIG. 30;

FIG. 32 is a flowchart illustrating an operation in the third embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 image simulation system 101 image input means 102 input image storage means 103 calculating means 104 dot reflectivity distribution data calculating means 105 dot position calculating means 106 reflectivity distribution calculating means 108 basic dot reflectivity distribution data 112 reflectivity distribution variation adding means 1200 Reflectance distribution correction means 1201 FET

Claims (29)

[Claims] A recording unit that records input image data; and a simulation of recording output of the recording unit.
Detecting means for detecting pixel data near the target pixel from the input image data; position calculating means for calculating a dot position of the target pixel based on the detected pixel data; and a target pixel detected by the detecting means Distribution data calculation means for calculating distribution data from the pixel data, and an image expected based on the dot position of each pixel calculated by the position calculation means and the distribution data of each pixel calculated by the distribution data calculation means And a reflectance distribution calculating means for calculating the reflectance distribution data. 2. The image processing apparatus according to claim 1, wherein the position calculating unit determines a predetermined position of a basic dot position calculated from recording density data corresponding to a recording density based on a state of neighboring pixel data of the target pixel detected by the detecting unit. 2. The image simulation apparatus according to claim 1, wherein a dot position of the pixel of interest is calculated by adding a variation amount. 3. The distribution data calculation means adds a predetermined variation to basic reflectance distribution data based on a state of neighboring pixel data of the pixel of interest detected by the detection means, and performs dot reflection on the pixel of interest. The image simulation apparatus according to claim 1, wherein rate distribution data is calculated. 4. The apparatus according to claim 1, wherein the reflectance distribution calculating means inputs the dot position of each pixel calculated by the position calculating means and the dot reflectance distribution data of each pixel calculated by the distribution data calculating means. The image simulation apparatus according to claim 1, wherein a reflectance distribution of an image expected to be output from the recording unit with respect to the image data is calculated. 5. The apparatus according to claim 1, wherein the reflectance distribution calculating means includes:
The image simulation apparatus according to claim 1, further comprising a deterioration characteristic correction unit configured to correct the calculated reflectance distribution according to one or more deterioration characteristics related to image formation of the recording unit. 6. A recording means for recording input image data, and: when simulating a recording output of said recording means,
Detecting means for detecting pixel data near the target pixel from the input image data; position calculating means for calculating a dot position of the target pixel based on the detected pixel data; and a target pixel detected by the detecting means Specific physical quantity distribution means for obtaining a distribution of the specific physical quantity of an image output from the recording means based on specific physical quantities such as density, brightness, luminance, etc. from the pixel data. Image simulation device. 7. The apparatus according to claim 1, wherein said position calculating means determines a predetermined dot position with respect to a basic dot position calculated from recording density data corresponding to a recording density based on a state of neighboring pixel data of the pixel of interest detected by said detecting means. The image simulation apparatus according to claim 6, wherein a dot position of the pixel of interest is calculated by adding a variation amount. 8. A recording unit for recording input image data, and: when simulating a recording output of the recording unit,
Position calculating means for calculating a dot position of a pixel of interest from the input image data; reflectance distribution data calculating means for calculating dot reflectance distribution data of the pixel of interest; and a dot position of each pixel detected by the detecting means. ,
Using the dot reflectance distribution data of each pixel calculated by the reflectance distribution data calculating means, a reflectance distribution calculating means for calculating a reflectance distribution of an image output from the recording means with respect to input image data, A reflectance variation data adding unit that adds reflectance variation data according to the characteristics of an image output target to the reflectance distribution of the image calculated by the reflectance distribution calculation unit. Simulation device. 9. The image simulation apparatus according to claim 8, wherein the position calculating means calculates recording density data corresponding to the recording density, fluctuation data of the dot position, and the dot position of each pixel. 10. The apparatus according to claim 9, wherein said reflectance distribution data calculating means calculates dot reflectance distribution data of each pixel from basic dot reflectance data and dot reflectance variation data. Image simulation device. 11. The image forming apparatus according to claim 11, further comprising a deterioration characteristic correction unit that corrects the reflectance distribution calculated by the reflectance fluctuation data adding unit according to one or more deterioration characteristics related to image formation of the recording unit. The image simulation device according to claim 8, wherein: 12. A recording unit for recording input image data, and: when simulating a recording output of the recording unit,
Detecting means for detecting pixel data near the target pixel from the input image data; position calculating means for calculating a dot position of the target pixel based on the detected pixel data; and a target pixel detected by the detecting means Specific physical quantity distribution means for obtaining the distribution of the specific physical quantity of the image output from the recording means based on the specific physical quantity such as density, brightness, luminance, etc. from the pixel data. Image simulation device. 13. A recording step of recording input image data, and in simulating a recording output of the recording step,
A detection step of detecting pixel data near the pixel of interest from the input image data; a position calculation step of calculating a dot position of the pixel of interest based on the detected pixel data; and a pixel of interest detected in the detection step. A distribution data calculation step of calculating distribution data from the pixel data, and an image predicted based on the dot position of each pixel calculated by the position calculation step and the distribution data of each pixel calculated by the distribution data calculation step A reflectance distribution calculating step of calculating the reflectance distribution data of the above. 14. The method according to claim 1, wherein the position calculating step is performed based on a state of pixel data in the vicinity of the target pixel detected in the detecting step. The dot position of the pixel of interest is calculated by adding the amount of variation, and the distribution data calculating step includes adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the neighboring pixel data of the pixel of interest detected in the detecting step. Calculating the dot reflectance distribution data for the pixel of interest by adding the dot position of each pixel calculated in the position calculation step and the dot reflection of each pixel calculated in the distribution data calculation step. Calculating a reflectance distribution of an image expected to be output from the recording step with respect to input image data, based on the reflectance distribution data; The image simulation method according to claim 13, wherein: 15. The method according to claim 15, wherein the reflectance distribution calculating step includes a deterioration characteristic correcting step of correcting the calculated reflectance distribution in accordance with one or more deterioration characteristics related to image formation in the recording step. An image simulation method according to claim 13 or claim 14, wherein 16. A recording step of recording input image data, and in simulating a recording output of the recording step,
A detection step of detecting pixel data near the pixel of interest from the input image data; a position calculation step of calculating a dot position of the pixel of interest based on the detected pixel data; and a pixel of interest detected in the detection step. And a specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of an image output from the recording step based on specific physical quantities such as density, brightness, and luminance from the pixel data. Image simulation method. 17. The apparatus according to claim 1, wherein the position calculating step includes a step of determining a predetermined position of a basic dot position calculated from recording density data corresponding to a recording density based on a state of neighboring pixel data of the target pixel detected in the detecting step. 17. The image simulation method according to claim 16, wherein a dot position of the pixel of interest is calculated by adding a variation amount. 18. A recording step of recording input image data, and in simulating a recording output of the recording step,
A position calculation step of calculating a dot position of a pixel of interest from the input image data; a reflectance distribution data calculation step of calculating dot reflectance distribution data of the pixel of interest; and a dot position of each pixel detected in the detection step. ,
Using the dot reflectance distribution data of each pixel calculated in the reflectance distribution data calculation step, a reflectance distribution calculation step of calculating a reflectance distribution of an image output from the recording step with respect to input image data, A reflectance variation data adding step of adding reflectance variation data according to the characteristics of an image output target to the reflectance distribution of the image calculated in the reflectance distribution calculating step. Method. 19. Further, in the position calculating step, recording density data corresponding to the recording density, dot position variation data, and dot position of each pixel are calculated, and in the reflectance distribution data calculating step, basic dot reflectance data is calculated. Calculating the dot reflectance distribution data of each pixel from the dot reflectance variation data, and applying the reflectance distribution calculated in the reflectance variation data adding step to one or more deterioration characteristics related to image formation in the recording step. 19. The image simulation method according to claim 18, further comprising a deterioration characteristic correction step for correcting the deterioration characteristic. 20. A recording step of recording input image data, and a step of simulating a recording output of the recording step,
A detection step of detecting pixel data near the target pixel from the input image data; a position calculation step of calculating a dot position of the target pixel based on the detected pixel data; and a target pixel detected in the detection step And a specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of an image output from the recording step based on specific physical quantities such as density, brightness, and luminance from the pixel data. Image simulation method. 21. A recording step of recording input image data, and a step of simulating a recording output of the recording step.
A detection step of detecting pixel data near the pixel of interest from the input image data; a position calculation step of calculating a dot position of the pixel of interest based on the detected pixel data; and a pixel of interest detected in the detection step. A distribution data calculation step of calculating distribution data from the pixel data, and an image predicted based on the dot position of each pixel calculated by the position calculation step and the distribution data of each pixel calculated by the distribution data calculation step A reflectance distribution calculating step of calculating the reflectance distribution data of the image simulation program. 22. The method according to claim 19, wherein the position calculating step includes a step of calculating a predetermined dot position with respect to the basic dot position calculated from the recording density data corresponding to the recording density based on the state of the neighboring pixel data of the target pixel detected in the detecting step. The dot position of the pixel of interest is calculated by adding the amount of variation, and the distribution data calculating step includes adding a predetermined amount of variation to the basic reflectance distribution data based on the state of the neighboring pixel data of the pixel of interest detected in the detecting step. Calculating the dot reflectance distribution data for the pixel of interest by adding the dot position of each pixel calculated in the position calculation step and the dot reflection of each pixel calculated in the distribution data calculation step. Calculating a reflectance distribution of an image expected to be output from the recording step with respect to input image data based on the reflectance distribution data; The image simulation program according to claim 21, wherein: 23. The method according to claim 23, wherein the reflectance distribution calculating step includes a deterioration characteristic correcting step of correcting the calculated reflectance distribution in accordance with one or more deterioration characteristics related to image formation in the recording step. An image simulation program according to claim 21 or claim 22, characterized in that: 24. A recording step of recording input image data, and a step of simulating a recording output of the recording step,
A detection step of detecting pixel data near the pixel of interest from the input image data; a position calculation step of calculating a dot position of the pixel of interest based on the detected pixel data; and a pixel of interest detected in the detection step. And a specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of an image output from the recording step based on specific physical quantities such as density, brightness, and luminance from the pixel data. Image simulation program. 25. The method according to claim 25, wherein the position calculating step includes a step of calculating a predetermined dot position from a basic dot position calculated from the recording density data corresponding to the recording density based on the state of the neighboring pixel data of the target pixel detected in the detecting step. The image simulation program according to claim 24, wherein a dot position of a pixel of interest is calculated by adding a variation amount. 26. A recording step of recording input image data, and a step of simulating a recording output of the recording step,
A position calculation step of calculating a dot position of a pixel of interest from the input image data; a reflectance distribution data calculation step of calculating dot reflectance distribution data of the pixel of interest; and a dot position of each pixel detected in the detection step. ,
Using the dot reflectance distribution data of each pixel calculated in the reflectance distribution data calculation step, a reflectance distribution calculation step of calculating a reflectance distribution of an image output from the recording step with respect to input image data, A reflectance variation data adding step of adding reflectance variation data according to the characteristics of an image output target to the reflectance distribution of the image calculated in the reflectance distribution calculating step. program. 27. Further, in the position calculating step, recording density data corresponding to the recording density, dot position variation data, and dot position of each pixel are calculated, and in the reflectance distribution data calculating step, basic dot reflectance data is calculated. Calculating the dot reflectance distribution data of each pixel from the dot reflectance variation data, and applying the reflectance distribution calculated in the reflectance variation data adding step to one or more deterioration characteristics related to image formation in the recording step. 27. The image simulation program according to claim 26, further comprising a deterioration characteristic correcting step of correcting the deterioration. 28. A recording step of recording input image data, and a step of simulating a recording output of the recording step,
A detection step of detecting pixel data near the pixel of interest from the input image data; a position calculation step of calculating a dot position of the pixel of interest based on the detected pixel data; and a pixel of interest detected in the detection step. And a specific physical quantity distribution step of obtaining a distribution of the specific physical quantity of an image output from the recording step based on specific physical quantities such as density, brightness, and luminance from the pixel data. Image simulation program. 29. A computer readable recording medium on which the image simulation program according to claim 21 is recorded.