Image processing apparatus, image display apparatus, image forming apparatus, image processing method and storage medium

An image processing apparatus comprising:

• a storage section for storing a plurality of different pixel patterns, indices indicating the respective pixel patterns, and contour vector information indicating contours appearing in the pixel patterns in association with each other;
• a decoding section for decoding image data, which has been encoded by replacing an image composed of a plurality of pixels on a block-by-block basis, each block consisting of a predetermined number of pixels, with any of the pixel patterns and representing the pixel patterns by the indices, on the block-by-block basis by referring to the storage section and using a pixel pattern indicated by an index representing the image data;
• and
• a scaling section for scaling a pixel pattern used for each block to be decoded by said decoding section and redrawing pixels near a contour in the pixel pattern after scaling by using the contour vector information corresponding to the pixel pattern,
• wherein said scaling section
• calculates a line segment vector corresponding to a contour according to a scale factor by using the contour vector information corresponding to an index representing the image data, and
• corrects pixel values of pixels near the contour after scaling the pixel pattern corresponding to the index so that the pixel values gradually decrease or increase according to distances from the line segment vector.