| 摘要 |
PURPOSE:To encode effectively an image having small ratio of intermediate tone on such as a writing and picture having high texture density, by assigning the shortest code to the specified condition having a high probability of generation. CONSTITUTION:The density level of an image signal is detected by a multiple quantizer 52 and further, the number of picture elements of the same density level (run length) are detected by a run length counter 54. In a condition decision circuit 56, within the detection results of multiple quantizer 52 and run length counter 54, one peculiar code is generated for a special combination having a high probability of generation, and as to the other combination, sets of peculiar code are respectively generated for density level and run length. |
