Patent ID: 9747533
Date: 2017-08-29
CPC Classifications: B41J,G06K

Claim:
1. An image processing apparatus that generates print data using a printing head having an ejection port array in which a plurality of ejection ports for ejecting inks is arrayed in a predetermined direction, the print data using the printing head in each of K (K≧3) times of relative scanning to a unit area on a printing medium in a crossing direction intersecting with the predetermined direction, and the print data determining ejection or non-ejection of ink to each of pixel-equivalent pixel regions in the unit area, the image processing apparatus comprising: a first acquiring unit configured to acquire image data in which information indicating the number of times of ejection of ink from zero to N (2≦N≦K) times for each of the plurality of pixel regions is determined for each pixel; a storage unit configured to store a first mask pattern in which information indicating the number of times of permission of ejection of ink from 0 to M (2≦M≦K) times for each of the plurality of pixel regions is determined for each pixel; a specifying unit configured to specify the first ejection port in which ejection failure of ink exists, of the plurality of ejection ports; a first selecting unit configured to select the information indicating the number of times of permission in the K pixels, of the information determined by the first mask pattern stored in the storage unit, the K pixels corresponding to K different ejection ports including at least the first ejection port specified by the specifying unit and capable of ejecting the inks to a same position to each other in the K times of scanning, and the K pixels being positioned in a same position to each other in the crossing direction; a second acquiring unit configured to acquire the information indicating the number of times of permission in a pixel corresponding to the first ejection port specified by the specifying unit, among the information selected by the first selecting unit; a third acquiring unit configured to acquire the information indicating the number of times of permission in a pixel corresponding to the second ejection port not specified by the specifying unit, among the information selected by the first selecting unit; a second selecting unit configured to select the first information having a smallest number of times of permission indicated by the information, from the information acquired by the third acquiring unit; a first generating unit configured to generate a second mask pattern by replacing the first information selected by the second selecting unit using the information acquired by the second acquiring unit when the number of times of permission indicated by the information acquired by the second acquiring unit is larger than the number of times of permission indicated by the first information selected by the second selecting unit; and a second generating unit configured to generate the print data based on the image data acquired by the first acquiring unit, and the second mask pattern generated by the first generating unit.