Patent ID: 8259347

Claim:
An image forming apparatus comprising: a first holding unit that holds a pixel value data sequence which represents an image element as an aggregation of one-dimensional data sequences and in which each of the data sequences is formed by a pixel value, a number of pixels of the pixel value to be repeated, and attribute information of the pixel value, or by the pixel value, the number of pixels of the pixel value to be repeated, reference to a reference pixel corresponding to image value arrangement data stored in a predetermined data holding unit, and a number of pixels of the reference pixel to be repeated; a second holding unit that holds a transparency data sequence in which each of the one-dimensional data sequences is formed by a coefficient representing transparency of a pixel value in the image element, a number of pixels of the coefficient to be repeated, and attribute information of the coefficient, or by the coefficient, the number of pixels of the coefficient to be repeated, reference to a reference coefficient corresponding to coefficient arrangement data pertaining to the coefficient held in the predetermined data holding unit, and a number of pixels of the reference coefficient to be repeated; and an image generation unit that forms an image from the pixel value data sequence held in the first holding unit, and that generates information about transparency of the image from the transparency data sequence held in the second holding unit.