VIDEO SIGNAL CODING METHOD AND DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the image quality by deciding a object code quantity in the unit of a prescribed image area based on a generated code quantity that depends on a quantization width, a generated code quantity that is independent thereof, and a total object code quantity and applying variable control to the quantization width so as to approach the generated code quantity to the object code quantity thereby preventing local deficiency of the shared code quantity. SOLUTION: A 1st coding circuit applies quantization and coding to a received image based on a fixed quantization width to generate a 1st generated code quantity that depends on the quantization width and a 2nd code quantization that is independent thereof respectively in a prescribed unit and they are stored in a storage circuit 2. A 2nd coding circuit 4 applies quantization with variable quantization width an coding to image data from an image delay buffer 3 and uses information of results of 1st and 2nd code quantities in the case of coding to set an object code quantity in the unit of pictures and also sets the object code quantity in the unit of blocks in each picture by using the object code quantity and the information of results of 1st and 2nd code quantities. Thus, local deficiency in the shared code quantity is prevented.