发明名称 |
High-efficiency coding apparatus for compressing a digital video signal while controlling the coding bit rate of the compressed digital data so as to keep it constant |
摘要 |
Digital video signals are divided in blocks, maximum and minimum values of each block are extracted, and a frequency distribution of one frame period of a dynamic range in each block is detected. The coding condition is determined by the frequency distribution and a predetermined N kinds of characteristic tables, and by determining only one characteristic table, the signal obtained by subtracting the minimum value of each block from the digital video signals of each block is coded in variable length according to the dynamic range of each block. The characteristic table shows the relationship of the distortion or the number of quantization bits between the original signal and decoded signal after coding and decoding with respect to the dynamic range of digital video signal in each block, and the picture quality of decoded image is set as a parameter.
|
申请公布号 |
US5307177(A) |
申请公布日期 |
1994.04.26 |
申请号 |
US19910794218 |
申请日期 |
1991.11.19 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
SHIBATA, HIDEAKI;BANNAI, TATSUSHI |
分类号 |
H04N1/415;G06T9/00;H04N7/26;(IPC1-7):H04N1/417;H04N7/12 |
主分类号 |
H04N1/415 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|