摘要 |
A method of coding a video signal at a fixed bit rate with use of a vector quantization codebook, wherein advantageous codebook updates are determined by comparing a coding error associated with a first provisional coding of a frame with a coding error associated with a second provisional coding of the frame. The first provisional coding uses a fixed available number of bits to code a frame with use of the unmodified codebook, whereas the second provisional coding uses a modified codebook to code the same frame. However, the second provisional coding codes both the frame and the codebook updates with the fixed available number of bits. The provisional coding having the smaller coding error is selected as the coding of the frame which will be adopted. In addition, the codebook may be replaced with the modified codebook when the second provisional coding is selected. In this manner, the coder will adapt the codebook to the characteristics of the scene.
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