| 摘要 |
PROBLEM TO BE SOLVED: To suppress a deterioration in image quality during decoding when dividing an image signal into a high region component and a low region component to encode each component.SOLUTION: Moving image data is divided into a high frequency moving picture data H composed of high frequency components of a spatial frequency and a low frequency moving picture data L composed of low frequency components. The low frequency moving picture data L is subjected to pixel thinning and entropy encoding. During thinning, pixels remaining in the thinning are used to perform curve approximation, finding out an error to the original low frequency moving picture data L, and the number of pixels to be subjected to thinning is determined on the basis of the found out error. A difference Lq between data obtained by the curve approximation and the low frequency moving picture data L is added to the high frequency moving picture data H, and compressedly encoded by an MPEG2 system, or the like. A stream by the low frequency moving picture data L subjected to the pixel thinning and the entropy encoding is synthesized with a stream in which the high frequency moving picture data H with the difference Lq added thereto is compressedly encoded and outputted as one stream. |
