JPS63114463A - Image processor - Google Patents

Abstract

PURPOSE:To reproduce a density area that an operator wants to reproduce so that it can be identical with its original by selecting luminous energy from an image based on the density of an image to be read in an area that a specification means specifies. CONSTITUTION:The operator places an original that he wants to copy on a digitizer 200 with the face up, and specifies a part that he especially wants to reproduce so as to be identical with its original with an input pen. Next, he places the original on an original glass platen with the bottom up, and measures the density at specified coordinates. If the density is high, a drive signal 12 is outputted to increase luminous energy inputted to an unmagnified color splitting line sensor 6, and an ND filter 48 is removed from an optical path. By increasing the luminous energy inputted to a CCD driver and amplifier 8 in such a way, an area with high density can be reproduced faithfully.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an image processing device, and particularly to an image processing device that reads and reproduces an image.

[Prior Art] Conventionally, this type of device can make the printed image darker or lighter, but it is not possible to finely adjust the gradation of only a portion of the shadow, for example. There were drawbacks such as it was difficult to distinguish between the hair of the person in front of the dark background and the background, and the pattern on black clothing that had a pattern disappeared, leaving the person looking like black clothing.

[Problems to be Solved by the Invention] The present invention provides an image processing device that eliminates the above-mentioned drawbacks and finely adjusts the gradation of a specified area. This provides an image processing device that can faithfully reproduce the density range that is desired to be reproduced, especially in the original.

[Means for Solving the Problem] As a means for solving this problem, the image processing apparatus of the present invention includes a designating unit for designating an area on an image to be read, and an area designated by the designating unit. and a selection means for selecting the amount of light from the image based on the density of the image to be read.

[Operation] In this configuration, the amount of light from the image is selected based on the density of the image to be read in the area specified by the specifying means.

[Embodiment] FIG. 1 shows a block diagram of an image processing apparatus according to this embodiment, and FIG. 2 shows an internal diagram of the image processing apparatus according to this embodiment.

FIG. 2 is an internal explanatory diagram of an image processing device consisting of a digitizer, a color image reading device, and a color image printer device, where 200 is a digitizer, 1 is a color image reading device (hereinafter referred to as color reader 1), and 2 is a color image processing device. This is an image printer device (hereinafter referred to as color printer 2).

First, place the original 201 you want to copy on the digitizer 2 facing upward.
00, and use the manual bender 202 to specify the part that you want to copy and reproduce with particular fidelity. The control board 15 in FIG. 1 stores the coordinates of this point.

Next, place the original 201 face down on the original glass and press the copy key.The original scanning unit 4 moves to the arrow A to read the image of the original 201 on the original glass in order to measure the density at the specified coordinates. At the same time as scanning in the direction of
The exposure lamp 7 in the document scanning unit 4 is turned on. Hara 1
The reflected light from 201 is guided to the rod array lens 5, passes through an ND filter 48 for reducing the amount of light, and forms an image on the same-magnification color separation line sensor 6.

The equal-magnification color separation line sensor 6 responds to the amount of light input.
Outputs color-separated analog image signals. This analog image signal is amplified by the COD driver & amplifier 8 in FIG. is sent to circuit 10. The control board 15 stores the value of the 8-bit digital image signal at a location previously designated by the digitizer 200.

By the way, when the original is a photograph, the black density is 2.6 or more and the white density is about 0.01, but the black density that can be reproduced with electrophotography is about 1.5. It is impossible to reproduce the exact same density as the original, and the relationship between the density of the original and the density of the printed image is
It will look like the figure. Note that the concentrations appearing in this example are:
It can be expressed by the following formula.

DC? ! A degree) = 1. og1/R However, since R is a reflective element, it is usually no use reading the high-density parts of the original in fine gradation, so the output of the 1-magnification color separation line sensor 6 is amplified and A/D converted. The relationship between the digital image signal obtained and the document density is shown in FIG.

Therefore, if the location specified by the digitizer 200 during blisscanning is a dark area, for example, around density 2.4, the 8-bit digital image signal value will be 14, as can be seen from FIG. This is the curved part of the graph, and the change in density is not proportional to the change in the image signal, so it is not possible to read minute changes in gradation.

In this embodiment, for example, when the density of a designated portion is 2.4 or more, the drive signal 12 is outputted to increase the amount of light input to the 1-magnification color separation line sensor 6.
Remove filter 48 from the optical path.

The relationship between the document density and the digital image signal at this time is as shown in FIG.

Thereafter, in order to actually output an image, the original scanning unit 4 in FIG. 2 moves and scans again in the direction of the arrow A, and at the same time turns on the exposure lamp 7 in the original scanning unit 4. The reflected light from the original is guided to a rod array lens 5 and focused on a 1-magnification color separation line sensor 6.

The same-magnification color separation line sensor 6 outputs color-separated image signals according to the amount of input light. This analog signal is amplified by the CCD driver & amplifier 8 in Figure 1, and
The signal is converted into an 8-bit, 256-gradation digital signal by the /D conversion circuit 9, and separated into each color by the serial-parallel conversion circuit 47.
A γ conversion circuit 10 performs γ conversion. One of the colors is selected by a selection signal 46 from the control board 15, and then the recording dot to be output is determined by comparing the density data of the pixel with a threshold value in order to reproduce halftones.

Well-known dither processing is performed in the dither circuit 11 in FIG. 1, and the image information converted into binary values is sent to the color blink 2.

FIG. 2 The binary image information sent to the color printer 2 is
Figure Laser driver 52 is manually powered, Laser driver 5
2 turns on the laser element 53 according to the image information
F L/ modulates the laser light. This modulated laser light is irradiated onto the photosensitive drum 101.

Before the photosensitive drum 101 is exposed to light, static electricity is removed by the removing electrode 102 shown in FIG. 1, and then charged by the f electrode 103, and an electrostatic latent image is formed on the photosensitive drum by the ON10 F F of the laser beam. .

Further, 105 is a developing device, yellow developing device 105Y.
, a magenta developer 105M, a cyan developer 105C, and a black developer 105. First, yellow development is performed by the yellow developer 105Y, which is set in advance at the development position shown in FIG. On the other hand, reference numeral 106 indicates a transfer drum, on which a film or mesh-like screen made of a conductor (not shown) is stretched.

Cassette 107, paper feed roller 109 or cassette 108
The transfer paper, which has passed through the paper feed guide 111 from the paper feed roller 110, is held by a gripper 112 built into the transfer drum 106, and is held by the corona of the charging electrode 113 to the electrostatic film or mesh screen. At this time, the electrostatic attraction effect is increased by pressing the transfer paper with the connectable pressing roller 114.

The transfer drum 106 rotates in synchronization with the photosensitive drum 101, and the visible image on the photosensitive drum 101, which has been developed yellow by the yellow developing device 105Y, is transferred onto the transfer paper by the transfer charging electrode 115.

The transfer drum 106 continues to rotate and prepares for transfer of the next color (magenta).

After the photosensitive drum 101 has been transferred onto the transfer paper, it is cleaned by the cleaning member 116, and then the charged electrode 1
03 to prepare for the next exposure by the laser 104. On the other hand, the photosensitive drum 103 is
After being cleaned by the charging electrode 103, it is charged by the charging electrode 103.

This process will be performed for magenta, cyan, and black.

When the transfer of yellow, magenta, cyan, and black is completed, the removal electrodes 11 provided on the inside and outside of the transfer drum
At step 7, for example, an AC high voltage is applied to release the gripper 112, and the image is separated by the transfer drum 106 by the separation claw 118 and sent to the fixing device 120 by the conveyor belt 119, where a copy image is formed.

FIG. 6 shows a configuration diagram of the control board 15, and FIG. 7 shows a flowchart of a processing program of the control board 15.

The control board 15 includes a CPυ 150, a ROM 151 that stores a processing program, and a RAM 1 for auxiliary storage that stores coordinates specified by a digitizer, specified flags, etc.
52, a signal input section 153 that inputs a signal from a digitizer or an A/D conversion circuit, and a signal output section 154 that outputs a signal to an ND filter or dither circuit.

First, step S1. In step S8, the process waits for the start key or the digitizer 200 to specify the position. If the start key is pressed without specifying a position by the digitizer 200, the process jumps from step S2 to step S7.
Normal playback processing is performed.

If a position is designated by the digitizer 200, the process goes from step S8 to step 59-10, where the coordinates of the designated position are stored and a designation flag indicating that the designation has been made is turned ON.

When the start key is pressed after the position is designated by the digitizer 200, steps S1→2→3 are followed, the document is scanned in step S3.4, and the density of the stored coordinates is obtained in step S9. The density is checked in step S5, and if it is small, the process jumps to step S7 and normal reproduction processing is performed. On the other hand, if the concentration is large, step S
In step S6, the ND filter is removed to increase the amount of light from the document, and the reproduction process in step S7 is performed. Here, the density is determined by comparing it with a predetermined value, and the value can be changed at any time.

Note that ND is a method of increasing the amount of light input to the CCD.
Although this was done by removing the filter, the amount of light from the lamp may also be increased by increasing the voltage applied to the lamp. However, in this case, the light emission distribution of the lamp shifts toward blue (B), so the contents of the γ conversion circuit 10 are switched to match the output of B and G.
Although it is necessary to reduce the output of the filter, this method also provides the same effect as removing the ND filter. Furthermore, in this example, a simple two-stage switching was performed, but more delicate adjustments can be made by performing finer switching.

Further, in this embodiment, the position of one point is specified, but a region may be specified by specifying a plurality of points.

As explained above, according to the present invention, when a printer has a high density area and wants to reproduce it with fine gradation, it is possible to faithfully reproduce the high density area by increasing the amount of light input to the COD.

[Effects of the Invention] According to the present invention, it is possible to provide an image processing device that finely adjusts the gradation of a designated area. As a result, it was possible to provide an image processing apparatus that faithfully reproduces the density range that is desired to be reproduced, especially in the original.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the image processing apparatus of this embodiment, Fig. 2 is an internal explanatory diagram of the image processing apparatus of this embodiment, and Fig. 3 is a diagram showing the relationship between the density of the original and the density of the printout. , Figure 4 is a diagram showing the relationship between document density and digital image signal during normal copying, Figure 5 is a diagram showing the relationship between document density and digital image signal when a high density area is specified; FIG. 6 is a configuration diagram of the control board, and FIG. 7 is a flowchart of the processing program of the control board. In the figure, 1...Color reader, 2...Color printer, 6...1-size color separation line sensor, 8...CC
D driver & amplifier, 9... A/D conversion circuit, 10
00. γ conversion circuit, 11... dither circuit, 12...
Drive signal, 15... Control board, 46... Selection signal, 47... Serial-parallel conversion circuit, 48... ND filter. Patent applicant Canon Co., Ltd. Go0 0.5 1.0 1.
5 2.0 2.5 White □ Black 7
i Sou Figure 4 Figure I3 and

Claims (3)

[Claims] (1) In an image processing device that reads and reproduces an image, there is a specifying means for specifying an area on the image to be read, and the amount of light from the image is selected based on the density of the image to be read in the area specified by the specifying means. An image processing device comprising a selection means for selecting. (2) The image processing apparatus according to claim 1, wherein the specifying means is a digitizer. (3) Image processing according to claim 1, wherein the selection means removes the filter from the optical path to increase the amount of light when the density of the designated area on the image is equal to or higher than a predetermined value. Device.