发明名称 |
Variable length coding method and apparatus for video compression |
摘要 |
A method and an apparatus to encode a series of quantized coefficients of a transform of a block of image data. The transform is such that 0 is the most likely coefficient amplitude and 1 is the next most likely coefficient amplitude. The method includes forming modes for each encountered non-zero amplitude and forming events for the modes in the mode-modified series formed by setting to zero all non-zero amplitudes other than the amplitude defining the mode. An event for modes for amplitudes greater than 1 is a run of none or more zero-valued coefficients followed a non-zero amplitude in the mode-modified series. In one embodiment, a first mode is defined for amplitude 1 wherein an event is a run of none or more zero-valued coefficients followed the amplitude 1 coefficient in the mode-modified series. In another embodiment, a first mode is defined for amplitude 1 wherein an event is a run in the mode-modified series of none or more zero-valued coefficients followed by a run of one of a predefined set of sequences, each sequence in the set being a sequence of 1's and 0's starting with a coefficient of amplitude 1. In another embodiment, a first mode is defined for amplitude 1 wherein an event is a sequence of 0's and 1's of the length of the series of quantized coefficients. The method includes forming a codeword for each encountered mode and forming codewords for the formed events in the mode. Relatively short codewords are formed to represent events that are relatively more likely to occur.
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申请公布号 |
US2004228540(A1) |
申请公布日期 |
2004.11.18 |
申请号 |
US20030439536 |
申请日期 |
2003.05.16 |
申请人 |
CHEN WEN-HSIUNG;WU FANG;PELTON GREGORY D. |
发明人 |
CHEN WEN-HSIUNG;WU FANG;PELTON GREGORY D. |
分类号 |
H03M7/40;H04N7/26;H04N7/30;H04N7/32;H04N7/50;(IPC1-7):G06K9/36 |
主分类号 |
H03M7/40 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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