| 摘要 |
PROBLEM TO BE SOLVED: To provide the method and device to use a full dynamic range for hybrid image processing operation while keeping a gray level used for a print. SOLUTION: The error spread method reduces the number of levels for a multi-level gradation picture element value denoting a picture element to spread an error caused by the reduction in the level number. This method receives a multi-level gradation picture element value denoting picture elements with a 1st resolution. The multi-level gradation picture element value is subjected to screen processing and the screen picture element value is equal to (GL-V1 )+(S1 -Th), where G1 is a maximum gray level of a picture element, V1 is a multi-level gradation picture element value with the 1st resolution, S1 is equal to a screen picture element value corresponding to the position of the picture element and Th is a threshold level. Then the level number of the multi-level gradation picture element value subjected to screen processing is reduced and an error is generated as a solution to the reproduction process. The error generated thereby is spread to the multi-level gradation picture element of an adjacent picture element. |
