Abstract: An image-area discrimination section in an image processing apparatus improves the accuracy of white-ground-region discrimination by more minutely classifying brightnesses with an edge discrimination section and a combination of the edge discrimination section and a contrast discrimination section.

Abstract: When a plurality of image data are to be compressed, an image correlation information extraction unit extracts respective image correlation information of image data, using first image data as reference image data. An encoding unit compresses the extracted image correlation information to produce encoded data. A data output unit outputs the compressed data and the reference image data to a page memory. When the compressed data are to be restored, a data input unit supplies the image correlation data input from the page memory to an image correlation information decoding unit, and supplies the reference image data to an image restoring unit. The image correlation information decoding unit decodes the image correlation data into the respective image correlation information and supplies the image correlation information to the image restoring unit. The image restoring unit restores the plural image data from the respective image correlation information and the reference image data.

Abstract: An image region discrimination section in an image processing apparatus subjects each pixel to a plurality of kinds of intermediate determinations as a pre-stage of a final attribute determination. Where necessary, the determination results are mutually referred to, and intermediate determination results are corrected once or more. The corrected intermediate determination results are synthesized to produce a final determination result.

Abstract: In an image region discrimination section in an image processing section, a characteristic signal calculation result obtained by hardware is subjected to macro-scoped correction and macro-discrimination by a processor. Further, in the image region discrimination section, a resolution and a signal bit number of a characteristic signals are decreased, the resultant characteristic signals is stored in a memory, and both a macro-discrimination result and the characteristic signals are synthesized to produce a final discrimination signal.

Abstract: In an image segmentation section in an image processing apparatus, a screen dot area judgment result, a line width judgment result, a color judgment result, a first edge detection result and a second edge detection result are respectively substituted by logic values to make judgment, and an image segmentation result is output.

Abstract: Not only one color conversion matrix is used for color conversion from a first color space to a second color space, but an appropriate color conversion parameter is calculated for each of a plurality of areas, into which the first color space is divided in advance. Further, an overlapping area is set between each set of adjacent ones of the divided areas of the first color space to construct a look-up table of a smaller conversion error.

Abstract: Plural line sensors are arranged parallel to each other in a predetermined order and with a predetermined interval, and they read different lines on a manuscript respectively. A delay module outputs an image signal output from at least one of the plural line sensors with a delay for a number of lines according to a number of pixels which corresponds to shifts of reading positions of the plural line sensors. An ahead-reading signal acquiring module outputs the image signal acquired from at least one line sensor other than a last stage line sensor of the plural line sensors as an ahead-reading signal. The image processing device outputs the image signal wherein the shifts of the reading positions of the plural line sensors are corrected by the delay module, and outputs the ahead-reading signal acquired by the ahead-reading signal acquiring module.

Abstract: Plural line sensors are arranged parallel to each other in a predetermined order and with a predetermined interval, and they read different lines on a manuscript respectively. A delay module outputs an image signal output from at least one of the plural line sensors with a delay for a number of lines according to a number of pixels which corresponds to shifts of reading positions of the plural line sensors. An ahead-reading signal acquiring module outputs the image signal acquired from at least one line sensor other than a last stage line sensor of the plural line sensors as an ahead-reading signal. The image processing device outputs the image signal wherein the shifts of the reading positions of the plural line sensors are corrected by the delay module, and outputs the ahead-reading signal acquired by the ahead-reading signal acquiring module.

Abstract: In an image processing apparatus, first image data and first discrimination data is generated on the basis of page information described in a page description language. Second discrimination data is generated on the basis of the generated first image data and first discrimination data. Second image data is generated on the basis of the generated second discrimination data and the first image data. An image processing is performed based on the generated second image data and second discrimination data, and the processed data is transferred on a printing medium.

Abstract: In an image processing apparatus, a first recognition section recognizes a black character portion and a color character portion in CMY color signals input from a color conversion section, and outputs a recognition result to a third recognition section. A second recognition section recognizes a low-density region (including a white portion) and a narrow region surrounded by the low-density region in the CMY color signals input from the color conversion section as a low-density region, and outputs a recognition result to the third recognition section. The third recognition section synthesizes the recognition result from the first recognition section and the recognition result from the second recognition section, and delivers a resultant recognition signal to a filtering section, a black signal generating section and a tone processing section.

Abstract: A number of character string determination sections determine whether a pixel of interest corresponds to a character or a line drawing. The character string determination sections use mutually different determination methods. A character determination selector section selects a determination result output from the character determination section that uses a determination method most suited to a background sensing result obtained by a background sensing section. In this manner, either the character or the line drawing can be determined using an efficient method in accordance with the background state of a color image.