Motion compensation method and device using bidirectional optical flow
摘要
說明書
In Embodiment 1 described above, the texture complexity of the current block is estimated using the pixels in the reference block. However, the texture complexity of the current block may be calculated using the actual pixels in the current block. For example, the encoding apparatus may calculate the horizontal complexity and the vertical complexity using the horizontal and vertical gradients of the pixels in the current block. That is, the horizontal complexity is calculated using the sum of squares of the horizontal gradients of the respective pixels in the current block, and the vertical complexity is calculated using the sum of squares of the vertical gradients. The horizontal and vertical complexities are then used to determine whether to skip the BIO process. In this case, unlike the encoding apparatus, the decoding apparatus does not know the pixels in the current block. Accordingly, the decoding apparatus cannot calculate the texture complexity in the same manner as the encoding apparatus. Therefore, the encoding apparatus should additionally signal information indicating whether BIO is skipped to the decoding apparatus. That is, the skip determiner implemented in the decoding apparatus decodes the information indicating whether to skip the BIO received from the encoding apparatus and selectively skips the BIO process as indicated by the information.
As described above, the CU corresponding to a leaf node of a tree structure, that is, the current block, may have various sizes according to the tree structure splitting from the CTU.
