JP2004088187A - Image processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high image quality and improve the usability even for outputting a copy in a system composed of a scanner and a printer connected to a computer. <P>SOLUTION: The image processor has a scanner 2 as an image inputting means and a printer 3 as an image outputting means connected through a computer 1. The scanner 2 comprises a means for processing a taken original copy image suitably to an output of the printer 3 before transferring the taken image to the computer 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image processing apparatus having a configuration in which image input means as a scanner and image output means as a printer are connected via a computer.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, printer image quality design is based on font data and graphic data of a word processor or the like, and the output image quality of raster data is not taken into account. On the other hand, the image quality design policy on the scanner side itself is intended to take in the read data without additional processing from the viewpoint of reading the original as faithfully as possible.
[0003]
In recent years, such printers and scanners are often connected to a computer, and are often used as a copier that immediately outputs a document read by the scanner to the printer.
[0004]
[Problems to be solved by the invention]
However, when the scan data is printed out in this manner, there arises a problem that only low-quality images can be obtained as compared with the output by the copying machine, such as blurred characters and thin lines, fogging of the background, and occurrence of moire.
[0005]
To improve this, if the user performs image processing on the raster data captured by the scanner using a computer-based photo retouching software, the image quality can be improved to some extent, but a lot of know-how is required. In addition, a user who desires quick output from the viewpoint of the quality obtained with respect to the work time cannot sufficiently satisfy the demand.
[0006]
Further, even if an attempt is made to output in an optimal print mode at the time of printing, normal printing and raster image printing cannot be automatically determined, and the user has to specify the printing.
[0007]
Furthermore, from the viewpoint of output speed, the speed of the interface for transferring the print image is low, and the output of the raster image takes an enormous amount of time for the print output of the normal font data. is not.
[0008]
The present invention solves the above-mentioned problems such as (1) raster image output image quality, (2) improvement in usability, and (3) reduction in output time, and can easily reduce image quality comparable to copy in a scan image in a short time. It is an object of the present invention to provide an image processing apparatus that can be obtained by the following.
[0009]
[Means for Solving the Problems]
In order to achieve such an object, the present invention provides an image processing apparatus to which an image input unit and an image output unit are connected via a computer. And image processing means for performing image processing suitable for output by the image output means on the original image.
[0010]
In the present invention, when an image of a document is fetched by the image input means and the data is transferred to the computer, the image is processed after being subjected to image processing suitable for output by the image output means. Thus, an image output suitable for output by the image output means can be quickly obtained without performing. That is, even with a system configuration in which an image input unit and an image output unit are connected via a computer, a copy output with excellent image quality can be obtained immediately.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a system configuration diagram of the image processing apparatus according to the present embodiment. That is, this image processing apparatus has a configuration in which a scanner 2 serving as image input means and a printer 3 serving as image output means are connected via a computer 1 such as a personal computer. The print data is sent to the printer 3 via the computer 1 to obtain a print output. Although FIG. 1 shows an example in which the scanner 2 and the printer 3 are directly connected to the computer 1 via a serial line or the like, the configuration may be such that they are connected via another network.
[0012]
In particular, the present embodiment is characterized in that image quality can be improved and processing speed can be shortened when performing a copy operation (so-called scan print) in which an image captured by the scanner 2 is immediately output by the printer 3.
[0013]
Here, the main image quality deterioration items when a document image is captured by the ordinary scanner 2 and printed using the data are shown below.
(1) Thin lines of characters and line drawings are blurred.
(2) The scalp is worn.
{Circle around (3)} Moire occurs in the halftone dot image portion.
[0014]
Therefore, in the present embodiment, from the viewpoint of preventing such deterioration in image quality, the scanner 2 is provided with an image processing means for performing image processing suitable for output by the printer 3 in advance.
[0015]
The image processing means is realized by an ASIC (Application Specific Integrated Circuit) provided in the scanner 2. FIG. 2 is a block diagram of the image processing apparatus according to the present embodiment. In the present embodiment, an ASIC implemented as an image processing unit of the scanner 2 includes image processing blocks of a color conversion unit 22, an edge enhancement unit 23, a background removal unit 24, a color conversion unit 25, and a γ correction unit 26. ing. Further, the printer 3 is provided with an image processing block for performing the error diffusion processing unit 33 as necessary.
[0016]
That is, the color conversion unit 22 converts the RGB data of the document image captured by the CCD (Charge Coupled Devices) 21 of the scanner 2 into Lab data. The edge emphasizing unit 23 performs an edge emphasizing process using the Lab data to sharpen the character.
[0017]
The background removing unit 24 removes a signal which becomes the background level of the original image to perform background removal processing, and the color conversion unit 25 converts Lab data into RGB data again. Further, the γ correction unit 26 performs a predetermined compression before the data is transferred to the computer 1 after the gradation correction is applied to the RGB data. By compressing the data, the data transfer time from the scanner 2 to the computer 1 can be reduced.
[0018]
In order to transfer data from the computer 1 to the printer 3, the color conversion unit 11 converts the data into YMCK (multi-valued) data, and the γ correction unit 31 of the printer 3 performs gradation conversion. Processing or moire removal processing by the error diffusion processing unit 33 is performed.
[0019]
Normally, in a system in which the scanner 2 and the printer 3 are connected to the computer 1, the scanner 2 is designed to exhibit a performance of faithfully reading a document as a function originally required, and output to the printer 3. It is not suitable for
[0020]
In the present embodiment, by providing the scanner 2 with image processing means for performing image processing suitable for output by the printer 3 in advance as described above, a document image captured by the scanner 2 is immediately output by the printer 3. However, it is possible to quickly obtain a high-quality print output without appropriately performing processing in the computer 1.
[0021]
Next, a flow from reading of a document by a scanner to print output will be described. First, when a scan instruction is issued from a scanner driver executed on the computer 1, for example, when scanning is performed in a unique mode called “Scan to Print mode”, the image data subjected to the above-described image processing is output from the scanner 2. Is done.
[0022]
The scanner driver converts the image data into a file on the computer 1 and adds some identification information indicating that the image data was scanned in this mode to the file. As a method of adding information to a file, any method of adding to a file header, adding to a file name, or embedding in image data itself may be used.
[0023]
In this embodiment, information is added to the file name. The addition of information to the file name has the advantages of (1) not fouling the file format, and (2) intuitively recognizing that the user has taken in by "Scan to Print".
[0024]
For example, when a document image is captured by “Scan to Print”, the file name is immediately preceding the extension such as “xxxxxx.extension” or “xxxxxx_s2p.extension”. A file name is generated by adding a discriminating symbol (in this example, $ or _s2p) indicating that the file is a file captured by “Scan to Print”.
[0025]
The discrimination symbol that is not usually used (or hardly used) may be set as a default, and the user may freely set the discrimination symbol from the scanner driver.
[0026]
Raster images captured in such a mode are specialized for document reproduction, and a certain degree of image quality improvement is expected even when output by an unspecified number of printers. However, in order to obtain an even better image, a combination with the processing on the printer side is effective. The operation at the time of printer output will be described below.
[0027]
Although this file can be output by a printer driver like a normal print file, printing in a mode that is uniquely added in the following two points provides higher image quality and usability.
[0028]
(A) Use of a screen optimal for raster image output. For example, processing is performed by the error diffusion processing unit 33 using an error diffusion screen in which moire is less likely to occur.
(B) In the case of a compressed file, the compressed file is transferred to the printer as it is.
[0029]
The additional information of the file described above is used when these are automatically executed (of course, the user can manually specify the additional information). Based on the additional information, the printer driver notifies the printer 3 that the print file is a “Scan to Print” file, and automatically selects an optimal screen.
[0030]
Regarding file transfer, even with a normal printer driver, even if the original file is a compressed file, it takes an enormous amount of time to transfer the data to the printer after it is first expanded into a raster file. There is an inconvenience.
[0031]
Therefore, in this embodiment, in order to greatly reduce the printing time, the compressed file is transferred to the printer in a compressed state, and the printer 3 expands the compression (at this time, the compression decompression is performed by the printer 3 itself). Configuration is required). As a result, the print output time can be significantly reduced.
[0032]
【The invention's effect】
As described above, the present invention has the following effects. That is, even if the image input unit (scanner) or the image output unit (printer) is connected via a computer, the image read by the image input unit is immediately printed out by the image output unit. And speeding up. This makes it possible to obtain a copy output comparable to a copying machine.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of an image processing apparatus according to an embodiment.
FIG. 2 is a block diagram of the image processing apparatus according to the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Computer, 2 ... Scanner, 3 ... Printer, 11 ... Color conversion part, 21 ... CCD, 22 ... Color conversion part, 23 ... Edge enhancement part, 24 ... Background removal part, 25 ... Color conversion part, 26 ... γ correction Unit, 31: γ correction unit, 32: screen processing unit, 33: error diffusion processing unit

Claims (5)

In an image processing apparatus to which an image input unit and an image output unit are connected via a computer,
The image input means is provided with image processing means for performing image processing suitable for output by the image output means on the document image before transferring the captured document image to the computer. Characteristic image processing device. 2. The image processing apparatus according to claim 1, wherein the image processing unit includes an edge enhancement unit that performs edge enhancement on the document image, and a background removal unit that removes background of the document image. 2. The image processing apparatus according to claim 1, wherein the image input unit includes a compression unit that compresses the original image processed by the image processing unit and transfers the compressed image to the computer. The image input unit, when transferring the document image processed by the image processing unit to the computer, informs that a file corresponding to the document image has been subjected to image processing suitable for output by the image output unit. 2. The image processing apparatus according to claim 1, further comprising an information adding unit for adding the information of (1). 2. The image processing apparatus according to claim 1, wherein the image output unit includes a moiré removing unit that removes moiré from the document image output from the computer.

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