JP6205893B2 - Image processing apparatus, image processing method, and program - Google Patents

Description

  The present invention relates to an image processing apparatus, an image processing method, and a program for performing toner saving of a solid portion.

  In recent years, in addition to a normal output mode that generates and outputs a high-quality image, an apparatus having a toner save mode that saves and outputs toner more than usual has been developed. The use case of the toner save mode is a case where the image quality is basically not so much, for example, the layout check of the output image.

  There are several methods for saving the toner consumption, such as density conversion, logical product of dithered image and thinning pattern, pulse width modulation and writing light quantity control. In any case, since the image density is reduced and output, the image quality is inferior to that in the normal output mode.

  However, even in the toner save mode, there is a demand to maintain readability without degrading image quality, especially for highly important character images. Therefore, by extracting the outline (edge) part of the image, assuming that the toner usage of the outline part is normal, and reducing the toner usage in the area other than the outline part, both character readability and saving of toner usage are achieved. The technique which performs is proposed (for example, refer patent document 1). A method for switching toner save processing with reference to object information has also been proposed. Proposes a technique to improve visibility when multiple objects overlap, for example, when characters are drawn on a filled object, when the background drawing color and the foreground character drawing color are nearly equal. (For example, see Patent Document 2).

  That is, object information such as characters, graphics, and photographs is identified by the type of printer command generated by the printer driver in the host computer, and line drawings and fills are identified for graphics. In addition, by switching to save toner for other objects without performing toner save for characters and line drawings, the readability of characters and line drawings is excellent and toner consumption is reduced. Output can be obtained.

  However, as described above, the solid toner save processing that improves the visibility of thin characters in solids will certainly improve the visibility of characters, but the solid portions do not look solid and are used in banners. When an image of a thick character, a stamp such as an electronic seal, or a character with a thin solid portion is output on paper, the solid portion image changes. Further, when the solid portion is output on paper in the same way as the original image, there is a problem that there is no toner saving effect.

The present invention has been made in view of the above problems,
An object of the present invention is to obtain a solid toner saving effect, and when outputting an image of a thick character used in a banner, a stamp such as an electronic seal, or a thin character of a solid portion on paper, An object of the present invention is to provide an image processing apparatus, an image processing method, and a program for performing toner save so that an image does not change.

In the present invention , the solid density is determined based on the image output means for writing a plurality of different patterns (hereinafter referred to as the first pattern) having a predetermined shape and the density detection information of the first pattern at the time of calibration. In accordance with the number of the first patterns, one pattern (hereinafter referred to as a second pattern) is determined based on the density detection information from a plurality of patterns in which the black pixels in the solid portion are replaced with white pixels. A first processing means to be selected in accordance with the selected second pattern with respect to predetermined image data input at the time of image output, and a black pixel in the solid portion of the image data is replaced with a white pixel. The main feature is that it includes a second processing means for performing toner saving to be replaced with.

  According to the present invention, when printing an image such as a thick character used in a banner, a stamp such as an electronic seal, or a character with a thin solid portion, the image is not changed and toner is saved in the solid portion. it can.

The structure of the Example of this invention is shown. The conventional structure is shown. The structure of the calibration process part of this invention is shown. A dot diameter determination pattern is shown. A solid part mask pattern is shown. 1 shows a configuration of an image processing unit of the present invention. The processing result of 84μ <X <126μ is shown. It is a figure explaining the effect of the thin character of a solid part by the comparison at the time of paper output of this invention (a) and the conventional (b). It is a figure explaining the effect of thick characters, such as a banner, by the comparison at the time of paper output of the present invention (a) and conventional (b). It is a figure explaining the effect of an electronic seal | sticker by the comparison at the time of paper output of this invention (a) and the conventional (b).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows the configuration of an embodiment of the present invention. The present invention includes a printer driver 102, a host computer 101 including application software 103, and an image processing apparatus 104 including an image processing unit 105, an image output unit 106, and a calibration processing unit 107. The calibration processing unit 107 selects one white pixel determination pattern from a plurality of white pixel determination patterns during calibration.

  When outputting an image, the image is transferred from the host computer 101 to the image processing apparatus 104 via the printer driver 102. The image processing unit 105 performs toner save on the transferred image by using the selected white pixel determination pattern to replace the solid black pixels with white pixels during paper output (image output), and outputs the image. The data is transferred to the unit 106.

  FIG. 2 shows a conventional configuration. An image is transferred from the host computer 101 to the image processing apparatus 104 via the printer driver 102. The image transferred to the image processing device 104 is transferred to the image output unit 106 after the image processing unit 105 in the image processing device 104 performs toner save so that the solid image is not filled during paper output.

  The present invention is different from the conventional configuration in that it includes a calibration processing unit capable of performing an optimal toner save in which a solid image is filled regardless of the state of the machine.

  FIG. 3 shows the configuration of the calibration processing unit. The calibration processing unit 107 determines the dot diameter of the white pixel using the dot diameter determination pattern generation unit 201 that generates a test pattern necessary for obtaining the dot diameter and the density detection information feedback from the image output unit 106. From the determination results of the dot diameter determination unit 202 and the dot diameter determination unit 202, a white pixel determination pattern that replaces black pixels in the solid part with white pixels is selected, and a solid part mask pattern selection unit 203 that sends the pattern information to the image processing apparatus 104 Consists of

  Calibration can be set automatically or manually. In the case of manual operation, a more effective toner save can be achieved by setting a solid density. If it is possible to make it a little thinner, if the solid density MAX1.4 is 1.2, the number of pixels that can be whitened is increased from 1.4. In the case of automatic, by setting the calibration to be performed once every time several sheets are output, it is possible to calibrate solid even if deterioration with time occurs.

  FIG. 4 shows a dot diameter determination pattern. (A) is a 1 × 1 pixel white pixel, (b) is a 2 × 2 white pixel, (c) is a 3 × 3 white pixel, and (d) is a 4 × 4 white pixel in the solid portion. The black and white pixels are arranged vertically and horizontally. These patterns are sent to the image output unit 106, recorded on the drum, and density detection information of a pattern recognized as solid by a sensor on the drum is sent to the dot diameter determination unit 202.

The dot diameter determination unit 202 makes the following determination based on density detection information indicating which pattern has a solid density (X is the dot diameter).
(A) to (d) Solid: 210 μ <X <252 μ
(A) to (c) Solid: 168 μ <X <210 μ
(A) to (b) Solid: 126 μ <X <168 μ
(A) Only solid: 84 μ <X <126 μ

  FIG. 5 shows a solid mask pattern. The pattern (a) is a pattern that makes 1 × 1 central pixels surrounded by 1 × 1 black pixels white, and the pattern (b) is 2 × 2 that is surrounded by 2 × 2 black pixels. A pattern for whitening the center pixels, (c) a pattern for whitening 3 × 3 center pixels surrounded by 3 × 3 black pixels, and a pattern for 4 × 4 (d) In this pattern, 4 × 4 central pixels surrounded by black pixels are whitened.

  The solid portion mask pattern shown in FIGS. 5A to 5D is selected according to the dot diameter determined by the dot diameter determining unit 202. If only (a) in FIG. 4 is solid, the pattern in FIG. 5 (a) is selected. If (a) and (b) in FIG. 4 are solid, the pattern in FIG. 5 (b) is selected. In the case of 4 (a) to (c) solid, the pattern of FIG. 5 (c) is selected, and in the case of (a) to (d) solid of FIG. 4, the pattern of FIG. 5 (d) is selected. .

  FIG. 6 shows the configuration of the image processing unit of the present invention. The image processing unit 105 includes a 3DLUT 301 that performs color correction, a γ correction unit 302 that performs density adjustment, a gradation processing unit 303 that matches 256 gradation data to the number of bits to be written, and a solid unit determination unit that detects a solid unit. Reference numeral 305 denotes a solid part processing unit 306 that performs solid part toner save processing.

  The images sent from the printer driver 102 of the host computer 101 are sequentially processed by the image processing unit 105 in FIG. The solid portion determined by the solid portion determination unit 305 is subjected to toner save processing in which the solid portion processing unit 306 in FIG. 6 replaces the black pixels in the solid portion with white pixels using the information in FIG.

  FIG. 7 shows a processing result of 84 μ <X <126 μ. (A) shows a processing result by the solid part toner save processing unit 304 in FIG. 6, and the black pixel at the center of the solid part is replaced with a white pixel. On the electronic image of (a), it is a process of replacing with white, but since the dots at the time of paper output of (b) are 84 to 126 μm, the white portion on the electronic image also becomes black due to the influence. Since the toner is not put on the overlapped portion (dotted line portion) again, toner can be saved by this amount.

  The larger the dot diameter, the more the toner gets on the solid part, resulting in unevenness. Even if it does not become uneven, the solid is filled, so the toner consumption can be reduced by the unevenness. The larger the dot diameter, the larger the area that can be whitened, so the toner saving effect is enhanced.

  FIG. 8 is a diagram for explaining the effect of characters with a thin solid portion by comparison between the present invention (a) and the prior art (b) at the time of paper output. In the conventional toner save, the density of both the solid part and the light character in the solid part is lowered, so that the solid part and the light character become the same density and become invisible. Therefore, although it has been improved that only the outer frame of the character is dark and cannot be seen, the solid part is not visible and the image is changed from the original image. On the other hand, in the present invention (a), the original image is output on paper without changing from the image.

  FIG. 9 is a diagram for explaining the effect of a thick character such as a banner by comparing the paper output of the present invention (a) and the prior art (b). On wide machines, banners may be printed, and the quality of the product becomes a problem if the thick black letters are poorly filled. In the conventional toner saving method (b), the characters are thinned and white gaps are formed in the thick characters by gradation processing, and the appearance is considerably poor. On the other hand, in the present invention (a), black is reproduced during paper output.

  FIG. 10 is a diagram for explaining the effect of the electronic seal by comparing the paper output of the present invention (a) and the prior art (b). In the conventional method (b), the electronic seal is thinned, a gap is formed by gradation processing, the seal is blurred and difficult to see, and toner saving cannot be performed. On the other hand, in the present invention (a), it is printed in the same manner as an image when paper is output, and it looks clear.

  As described above, according to the present invention, in the toner saving process for the solid portion, the toner saving is performed by using the information on the writing dot diameter to whiten the solid portion pixels so that the solid portion is filled when paper is output. As a result, the toner can be saved in the solid portion without changing the image.

  According to the present invention, a storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or apparatus, and the computer (CPU or MPU) of the system or apparatus is stored in the storage medium. It is also achieved by reading and executing the program code. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment. As a storage medium for supplying the program code, for example, a hard disk, an optical disk, a magneto-optical disk, a nonvolatile memory card, a ROM, or the like can be used. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on an instruction of the program code. A case where part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing is also included. Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. A case where the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing is included. Further, the program for realizing the functions and the like of the embodiments of the present invention may be provided from a server by communication via a network.

DESCRIPTION OF SYMBOLS 101 Host computer 102 Printer driver 103 Application software 104 Image processing apparatus 105 Image processing part 106 Image output part 107 Calibration processing part

JP 2009-172970 A JP 2010-214665 A

Claims (6)

At the time of calibration, the image output means for writing a plurality of different patterns (hereinafter referred to as first patterns) having a predetermined shape, and the first density determined to be a solid density based on the density detection information of the first pattern According to the number of patterns, one pattern (hereinafter referred to as a second pattern) is selected from a plurality of patterns in which the black pixels in the solid portion are replaced with white pixels according to the dot diameter determined based on the density detection information. Toner save that replaces black pixels in the solid portion of the image data with white pixels by using the selected second pattern for the predetermined image data that is input at the time of image output with the first processing means An image processing apparatus comprising: a second processing unit that implements the above. The first pattern, the image processing apparatus according to claim 1, characterized in that the test pattern for determining the dot diameter. The test pattern is a pattern in which n × n (n = 1, 2, 3,...) White pixels are arranged every other black pixel vertically and horizontally in a solid portion. Item 3. The image processing apparatus according to Item 2.   The image processing apparatus according to claim 1, wherein the second pattern is a pattern in which n × n central pixels surrounded by n × n black pixels are replaced with white pixels. At the time of calibration, the first output determined to be a solid density based on an image output step of writing a plurality of different patterns (hereinafter referred to as a first pattern) having a predetermined shape and density detection information of the first pattern . According to the number of patterns, one pattern (hereinafter referred to as a second pattern) is selected from a plurality of patterns in which the black pixels in the solid portion are replaced with white pixels according to the dot diameter determined based on the density detection information. Toner save that replaces black pixels in the solid portion of the image data with white pixels using the selected second pattern for the predetermined image data that is input during the first processing step and image output The image processing method characterized by including the 2nd process process which implements.   A program for causing a computer to realize the image processing method according to claim 5.