| 摘要 |
PURPOSE:To reduce the degradation of picture quality at the important part of an image by allocating a quantizing matrix reducing the degradation to the important part of the image and allocating a quantizing matrix enlarging the degradation to the non-important part of the image. CONSTITUTION:An image dividing part 1 divides the images into the part having important meaning and the other part. Next, the image divided by a block dividing part 2 is further divided into units for executing orthogonal transformation such as the blocks of 8X8 picture elements, for example, and an orthogonal transformation part 3 executes the orthogonal transformation. A quantizing table allocation part 6 allocates the quantizing table for each unit divided by the picture dividing part 1. In that case, the table reducing the degradation of picture quality in the case of executing compression/extension is allocated to the part having the important meaning, and the quantizing table enlarging the degradation of picture quality is allocated to the other part. According to the respective quantizing tables, a quantizing part 4 executes quantizing, and the result is transmitted to a transmission line after executing variable length encoding at a variable length encoding part 5. |
