Image processing apparatus for data compression, control method, and computer-readable medium

A control method of an image processing apparatus, which applies correction processing to input image data, comprising:

• a compression step of controlling a compression unit to compress the image data based on values of pixels and a layout of the pixels for each tile including the predetermined number of pixels;
• a representative value calculation step of controlling a representative value calculation unit to calculate a representative value from the values of the pixels included in the tile;
• a determination step of controlling a determination unit to determine based on a distribution of the representative values of tiles included in a first area including the first number of tiles whether or not a tile of interest included in the first area is to be corrected;
• a correction value calculation step of controlling a correction value calculation unit to calculate a correction value for the tile of interest based on the representative values of tiles included in a second area including the second number of tiles;
• and
• an addition step of controlling an addition unit to add representative values of the tiles, determination results of the tiles by the determination unit, and the correction value to the image data compressed in the compression step.

A non-transitory computer-readable medium storing a program for controlling a computer to function as:

• a compression unit configured to compress image data based on values of pixels and a layout of the pixels for each tile including the predetermined number of pixels;
• a representative value calculation unit configured to calculate a representative value from the values of the pixels included in the tile;
• a determination unit configured to determine based on a distribution of the representative values of tiles included in a first area including the first number of tiles whether or not a tile of interest included in the first area is to be corrected;
• a correction value calculation unit configured to calculate a correction value for the tile of interest based on the representative values of tiles included in a second area including the second number of tiles;
• and
• an addition unit configured to add representative values of the tiles, determination results of the tiles by said determination unit, and the correction value to the image data compressed by said compression unit.