| 主权项 |
1. A video encoding and decoding system comprising:
a video encoding apparatus for generating video encoding information by dividing each frame of a video into blocks of a predetermined size and by encoding blocks by using a quantization parameter defined corresponding to the blocks of the predetermined size, the video encoding apparatus including: an orthogonal transform unit configured to compress information of image data in a spatial direction; and a quantization unit configured to quantize an orthogonal transform coefficient of the image data that is orthogonal-transformed by the orthogonal transform unit, wherein the quantization unit divides the blocks of the predetermined size into sub-blocks based on quantization division information for dividing the blocks of the predetermined size into the sub-blocks of a size smaller than the predetermined size, each of which is quantized by using the quantization parameter according to an image property, quantizes the orthogonal transform coefficient by using a quantization parameter decided for each of the sub-blocks, and encodes the decided quantization parameter for each of the sub-blocks, each of the sub-blocks for which the quantization parameter is decided has a size equal to or larger than a block size that is a unit of processing in the orthogonal transform, the quantization unit quantizes a difference of a quantization parameter, which is used to quantize the orthogonal transform coefficient, from a more suitable quantization parameter among quantization parameters of encoded neighboring blocks of the predetermined size or sub-blocks, the more suitable quantization parameter is an intermediate value of the quantization parameters of the encoded neighboring blocks of the predetermined size or sub-blocks, when a plurality of left blocks that are adjacent to an left end of the sub-block to be encoded are present and a plurality of upper blocks that are adjacent to an upper end of the sub-block to be encoded are present as an encoded block of the predetermined size or an encoded sub-block, a difference between an intermediate value between a quantization parameter of further upper block among the left blocks and a quantization parameter of further left block among the upper blocks, and a quantization parameter the sub-block to be encoded is encoded; and a video decoding apparatus for decoding the video encoded by the video encoding apparatus including: a quantization division obtaining unit configured to obtaining the quantization division information set in the video encoding information; and an inverse quantization unit configured to perform inverse quantization for an orthogonal transform coefficient quantized for each of sub-blocks according to the obtained quantization division information in a block of the predetermined size to be processed. |
