Video encoding apparatus and video decoding apparatus

摘要

While maintaining a high degree of freedom in choosing partition sizes and transformation sizes adapted for local characteristics of videos, the amount of metadata is decreased. A video encoding apparatus (10) divides an input video into blocks of a prescribed size and encodes the video block by block. The video encoding apparatus is provided with: a prediction parameter determining portion (102) that decides the block partition structure; a predictive image producing portion (103) that generates predictive images, partition by partition, as prescribed by the partition structure; a transform coefficient producing portion (107) which applies one of the frequency transformations included in a prescribed transformation preset to prediction residuals, i.e. the differences between predictive images and the input video; a transform restriction deriving portion (104) which generates the list of transform candidate, i.e. lists of frequency transformations that can be applied to each partition, on the basis of partition format information; and a variable-length-encoding portion (108) which, on the basis of the list of transform candidate and the transformation preset, performs variable-length encoding on transformation selection flags.

主权项

1. A video encoding apparatus that divides an input video into predetermined size blocks and executes an encoding processing for each block, comprising:
a prediction parameter determining portion that determines a partition structure of the block; a predictive image producing portion that produces a predictive image for each partition specified by the partition structure; a transform coefficient producing portion that applies any one of transforms included in a predetermined transform preset to a prediction residual that is a difference between the predictive image and the input video; a transform candidate deriving portion that determines a list of transform candidate that is a list of applicable transforms based on partition shape information, which partition shape information characterizes each partition with respect to at least one of partition size, a feature of partition size, and a layer in the partition structure; a frequency transform determining portion that, for each of the blocks, determines a transform selection flag indicating transforms to be applied to the prediction residual in the block from among transforms included in the list of transform candidate; and a variable-length-encoding portion that variable-length-codes the transform selection flag based on the list of transform candidate.