公开(公告)号：US06111913A

公开(公告)日：2000-08-29

申请号：US859544

申请日：1997-05-20

申请人： John Ashley Murdock ,  Agnes Yee Ngai ,  Stephen Philip Pokrinchak

发明人： John Ashley Murdock ,  Agnes Yee Ngai ,  Stephen Philip Pokrinchak

IPC分类号： H04N7/30 ,  H04N7/26 ,  H04N7/50

CPC分类号： H04N19/42 ,  H04N19/126 ,  H04N19/132 ,  H04N19/152 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61 ,  H04N19/149 ,  H04N19/15 ,  H04N19/70

摘要： An MPEG2 compliant digital video encoder system employs an I-frame video encoder module having a quantization unit and variable length encoding to encode coefficients of each macroblock of a picture. Bit regulation schemes are presented for constraining selected coefficients of a macroblock if the bit rate of two prior macroblocks in a row exceeded a bit rate limit, or if the bit rate of the current nonintra macroblock is greater than a predetermined megabits per second (Mbps) limit. Pattern constraining is implemented within the quantization unit. For nonintra pictures, the conventional variable length coding process is modified to generate a Fixed Coded Block Pattern (FCBP) header for each macroblock of the picture for outputting in the bitstream prior to coding of the coefficients. The FCBP signifies that each block of the macroblock contains at least one nonzero coefficient. The regulation scheme then ensures that each block of the macroblock includes at least one nonzero coefficient by setting one of the coefficients in an all zeros block to a nonzero value.

摘要翻译： MPEG2兼容的数字视频编码器系统采用具有量化单位和可变长度编码的I帧视频编码器模块来编码图像的每个宏块的系数。 如果一行中的两个先前宏块的比特率超过比特率限制，或者如果当前nonintra宏块的比特率大于每秒预定兆比特（Mbps），则给出限制宏块的选定系数的比特调节方案， 限制。 模式约束在量化单元内实现。 对于非暗视频图像，常规可变长度编码处理被修改以在图像的每个宏块之前生成用于在编码系数之前在比特流中输出的固定编码块模式（FCBP）头部。 FCBP表示宏块的每个块包含至少一个非零系数。 调节方案然后通过将全零块中的系数之一设置为非零值来确保宏块的每个块包括至少一个非零系数。

公开(公告)号：US06999511B1

公开(公告)日：2006-02-14

申请号：US09255892

申请日：1999-02-23

申请人： Charles Edward Boice ,  James David Greenfield ,  John Mark Kaczmarczyk ,  Agnes Yee Ngai ,  Stephen Philip Pokrinchak

发明人： Charles Edward Boice ,  James David Greenfield ,  John Mark Kaczmarczyk ,  Agnes Yee Ngai ,  Stephen Philip Pokrinchak

IPC分类号： H04B1/66

CPC分类号： H04N19/126 ,  H04N19/159 ,  H04N19/174 ,  H04N19/186 ,  H04N19/61

摘要： A digital video encoder is presented adapted for dynamically switching between sets of quantizer matrix tables without pausing encoding of a stream of video data. Two or more sets of quantizer matrix tables are held at the encoder's quantization unit and compressed store interface for dynamically switching between sets of quant matrix tables at a picture boundary of the sequence of video data, i.e., without stopping encoding of the sequence of video data. Further, while one set of matrix tables is being employed to quantize the stream of video data, the encoder can be updating or modifying another set of quantization matrix tables, again without stopping encoding of the sequence of video data.

摘要翻译： 呈现适于在不暂停视频数据流的编码的情况下在量化器矩阵表的集合之间动态切换的数字视频编码器。 在编码器的量化单元和压缩存储接口处保存两组或多组量化器矩阵表，用于在视频数据序列的图像边界处动态切换量化矩阵表的集合，即不停止对视频数据序列的编码 。 此外，当采用一组矩阵表来量化视频数据流时，编码器可以在不停止对视频数据序列的编码的情况下，更新或修改另一组量化矩阵表。