公开(公告)号：US06434197B1

公开(公告)日：2002-08-13

申请号：US09226796

申请日：1999-01-07

申请人： Limin Wang ,  Ajay Luthra

发明人： Limin Wang ,  Ajay Luthra

IPC分类号： H04N718

CPC分类号： H04N21/23655 ,  H04N19/117 ,  H04N19/162 ,  H04N19/172 ,  H04N19/40 ,  H04N19/80 ,  H04N19/86

摘要： A method and apparatus for transcoding digital video data, for example, at the headend of a cable or satellite television network. A generic multi-functional transcoder architecture has a “post-pre-processing engine” that provides a number of processing functions for implementing desired format conversions according to a user selection signal or an automatically generated selection signal. The processing functions can change frame size, frame rate, color space sampling format, interlaced or progressive scan format, resolution, and provide noise/deblocking filtering, for example. The system also allows the control of several transcoders to convert several bit streams with different formats into corresponding bit streams with a common format. Furthermore, the transcoder avoids the need for motion estimation.

摘要翻译： 一种用于例如在有线或卫星电视网络的前端对数字视频数据进行代码转换的方法和装置。 通用多功能代码转换器架构具有“后预处理引擎”，其提供用于根据用户选择信号或自动生成的选择信号来实现所需格式转换的多个处理功能。 处理功能可以改变帧大小，帧速率，色彩空间采样格式，隔行或逐行扫描格式，分辨率，并提供噪声/去块滤波。 该系统还允许控制多个代码转换器，将具有不同格式的多个比特流以通用格式转换成相应的比特流。 此外，代码转换器避免了对运动估计的需要。

公开(公告)号：US07020198B2

公开(公告)日：2006-03-28

申请号：US10131414

申请日：2002-04-22

申请人： Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

发明人： Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

IPC分类号： H04N7/12 ,  H04N11/04 ,  H04N11/02

CPC分类号： H04N21/23655 ,  H04N19/114 ,  H04N19/152 ,  H04N19/157 ,  H04N19/159 ,  H04N19/172 ,  H04N19/177 ,  H04N19/40 ,  H04N19/577 ,  H04N19/61

摘要： A rate control system suitable for use with a digital video transcoder, such as one conforming to the MPEG standard. The proposed rate control system starts coding with any reasonable set of assumed Group of Pictures (GOP) parameters, thereby avoiding a processing delay of about one GOP which would otherwise be incurred to extract the complete GOP structure information from a pre-compressed bit stream. In addition, the system avoids the need to store the data corresponding to the GOP, thereby reducing the memory required for transcoding. Encoding of a first picture in a sequence or GOP begins without a priori knowledge of the picture type of subsequent pictures. A reasonable set of GOP parameters is assumed to determine an encoding bit budget. The bit budget is gradually corrected as successive pictures are coded according to their picture types. Changes in the GOP structure of pre-compressed bitstreams can be addressed, for example, when switching channels, inserting commercials, and the like. Target rates with incorrect starting GOP parameters will converge within a few GOPs.

公开(公告)号：US06570922B1

公开(公告)日：2003-05-27

申请号：US09198867

申请日：1998-11-24

申请人： Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

发明人： Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

IPC分类号： H04N712

CPC分类号： H04N21/23655 ,  H04N19/114 ,  H04N19/152 ,  H04N19/157 ,  H04N19/159 ,  H04N19/172 ,  H04N19/177 ,  H04N19/40 ,  H04N19/577 ,  H04N19/61

摘要： A rate control system suitable for use with a digital video transcoder, such as one conforming to the MPEG standard. The proposed rate control system starts coding with any reasonable set of assumed Group of Pictures (GOP) parameters, thereby avoiding a processing delay of about one GOP which would otherwise be incurred to extract the complete GOP structure information from a pre-compressed bit stream. In addition, the system avoids the need to store the data corresponding to the GOP, thereby reducing the memory required for transcoding. Encoding of a first picture in a sequence or GOP begins without a priori knowledge of the picture type of subsequent pictures. A reasonable set of GOP parameters is assumed to determine an encoding bit budget. The bit budget is gradually corrected as successive pictures are coded according to their picture types. Changes in the GOP structure of pre-compressed bitstreams can be addressed, for example, when switching channels, inserting commercials, and the like. Target rates with incorrect starting GOP parameters will converge within a few GOPs.

摘要翻译： 一种适用于数字视频转码器的速率控制系统，例如符合MPEG标准的数字视频转码器。 所提出的速率控制系统以任何合理的假想图像组（GOP）参数开始编码，从而避免了大约一个GOP的处理延迟，否则将从预压缩位流中提取完整的GOP结构信息。 此外，系统避免了存储对应于GOP的数据的需要，从而减少了转码所需的存储器。 序列或GOP中的第一图像的编码开始于对随后图像的图像类型的先验知识。 假设合理的GOP参数集合来确定编码比特预算。 随着连续的图像根据图像的类型被编码，位预算逐渐被校正。 可以解决预压缩比特流的GOP结构的变化，例如，当切换频道，插入商业广告等时。 具有不正确起始GOP参数的目标速率将在几个GOP内收敛。

公开(公告)号：US06259741B1

公开(公告)日：2001-07-10

申请号：US09252135

申请日：1999-02-18

申请人： Xuemin Chen ,  Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

发明人： Xuemin Chen ,  Limin Wang ,  Ajay Luthra ,  Robert O. Eifrig

IPC分类号： H04N712

CPC分类号： H04N19/186 ,  H04N19/40

摘要： A system for converting the color format of a digital video bitstream. The system accounts for the allowable formats of the pre- and-post-conversion bitstreams, including quantizer precision level, and whether luma and chroma data have separate quantization matrices, or share a common quantization matrix. In a particular implementation, an MPEG-2 4:2:2 P bitstream having a color format of 4:2:2 or 4:2:0 is converted to a MP bitstream having a color format of 4:2:0. Coding efficiencies are achieved by using the luma quantization matrix to re-quantize the chroma data, and re-using luma motion vectors for performing motion compensation of the chroma data. Further efficiencies can be achieved by representing a 4:2:2 reference picture in a 4:2:0 format for converting inter coded frames, and changing the position of a pixel downsizing filter and clip function. Adjustment of the quantization precision is provided as required. A transcoding function can also be achieved.

摘要翻译： 一种用于转换数字视频比特流的颜色格式的系统。 系统考虑了前后转换比特流的允许格式，包括量化器精度级别，以及亮度和色度数据是否具有单独的量化矩阵，或共享公共量化矩阵。 在具体实现中，将具有4:2:2或4:2:0的颜色格式的MPEG-2 4：2：2比特流转换为具有4:2:0的颜色格式的MP比特流。 通过使用亮度量化矩阵来重新量化色度数据并且重新使用亮度运动矢量来执行色度数据的运动补偿来实现编码效率。 通过以4：2：0格式表示4：2：2参考图像来转换帧间编码帧，并改变像素缩小滤波器和剪辑功能的位置，可以实现更高的效率。 根据需要提供量化精度的调整。 还可以实现转码功能。

公开(公告)号：US06441754B1

公开(公告)日：2002-08-27

申请号：US09642925

申请日：2000-08-17

申请人： Limin Wang ,  Ajay Luthra ,  Paul Moroney

发明人： Limin Wang ,  Ajay Luthra ,  Paul Moroney

IPC分类号： H03M700

CPC分类号： H04N19/162 ,  H04N5/4401 ,  H04N5/76 ,  H04N5/781 ,  H04N5/782 ,  H04N9/7921 ,  H04N9/8042 ,  H04N19/40 ,  H04N19/51 ,  H04N19/90 ,  H04N21/4147 ,  H04N21/4334 ,  H04N21/4351 ,  H04N21/440254 ,  H04N21/4622 ,  H04N21/47 ,  H04N21/8545

摘要： The present invention provides a transcoding architecture and a consumer set-top box with storage capability that is based on the transcoding architecture and capable of operating efficiently in an all-digital environment. In a preferred embodiment, a digital-VIDEO DEVICE employs an MPEG-2 compliant transcoder that includes a simplified cascaded decoder and encoder, and is capable of performing determinable bitrate re-encoding without conducting motion estimation. During recording, the decoder receives and processes a compressed source bitstream, producing a decoded bitstream that includes reconstructed video and preserved motion vectors. The encoder “re-encodes” the decoded bitstream using the preserved motion vectors and performs any applicable bitrate modifications. The re-encoded bitstream is then stored.

摘要翻译： 本发明提供一种具有存储能力的代码转换架构和消费者机顶盒，其基于代码转换架构并且能够在全数字环境中有效地运行。 在优选实施例中，数字视频设备采用符合MPEG-2的代码转换器，其包括简化的级联解码器和编码器，并且能够执行可确定的比特率重新编码而不进行运动估计。 在记录期间，解码器接收并处理压缩源比特流，产生包括重构的视频和保存的运动矢量的解码比特流。 编码器使用保留的运动矢量对解码的比特流进行“重新编码”，并执行任何适用的比特率修改。 然后存储重新编码的比特流。

公开(公告)号：US20090161697A1

公开(公告)日：2009-06-25

申请号：US11960446

申请日：2007-12-19

申请人： Limin Wang ,  Xue Fang ,  Vivian Kung ,  Ajay Luthra ,  Yinqing Zhao ,  Jian Zhou

发明人： Limin Wang ,  Xue Fang ,  Vivian Kung ,  Ajay Luthra ,  Yinqing Zhao ,  Jian Zhou

IPC分类号： H04J3/22

CPC分类号： H04N21/4347 ,  H04N19/40 ,  H04N21/234354 ,  H04N21/2365 ,  H04N21/23655 ,  H04N21/2383 ,  H04N21/2385

摘要： A StatMux system and method are provided for efficiently allocating time slots on the transmission channel between bit streams representing video and bit streams representing data. By providing such a system and method, when a decreased number of data bits need to be transmitted, a decreased number of time slots may be allocated for transmitting the data bits and an increased number of time slots may be allocated for transmitting video bits. When a decreased number of video bits needs to be transmitted, a decreased number of time slots may be allocated for transmitting video bits and an increased number of time slots may be allocated for transmitting data bits.

摘要翻译： 提供了一种StatMux系统和方法，用于在表示视频的比特流和表示数据的比特流之间有效地分配传输信道上的时隙。 通过提供这样的系统和方法，当需要发送数据比特数减少时，可以分配减少数量的时隙用于发送数据比特，并且可以分配更多数量的时隙用于发送视频比特。 当需要发送减少数量的视频位时，可以分配减少数量的时隙用于发送视频比特，并且可以分配增加数量的时隙用于发送数据比特。

公开(公告)号：US06434195B1

公开(公告)日：2002-08-13

申请号：US09196709

申请日：1998-11-20

申请人： Ajay Luthra ,  Keith J. Kelley ,  Limin Wang

发明人： Ajay Luthra ,  Keith J. Kelley ,  Limin Wang

IPC分类号： H04N712

CPC分类号： H04N21/812 ,  H04N19/00 ,  H04N19/107 ,  H04N19/157 ,  H04N19/172 ,  H04N19/174 ,  H04N19/40 ,  H04N19/48 ,  H04N19/61 ,  H04N21/23424 ,  H04N21/2343 ,  H04N21/26233 ,  H04N21/44016 ,  H04N21/8455

摘要： A method is provided for replacing compressed video from a first source with video from a second source at a predefined insertion point in a video data stream. If the video from the second source is progressively refreshed video, it is decompressed sufficiently prior to the insertion point to enable the recovery and recompression of a first video frame (in encoding order) from the second source to be inserted at the insertion point. The recovered first video frame is then recompressed as an intra-coded (I) frame. The insertion of the video from the second source is then commenced at the insertion point using the I frame. The insertion point can, for example, indicate the commencement of a commercial break in the video stream, in which case the second source provides a commercial for insertion into the commercial break. Where the commercial is stored in memory, it can be stored with the first frame thereof (in encoding order) as an I frame.

摘要翻译： 提供了一种用于在视频数据流中的预定插入点处从来自第二源的视频替换来自第一源的压缩视频的方法。 如果来自第二源的视频是逐渐刷新的视频，则在插入点之前对其进行充分的解压缩，以便能够从插入点插入第二个源的第一个视频帧（以编码顺序）的恢复和重新压缩。 然后将恢复的第一视频帧作为帧内编码（I）帧重新压缩。 然后使用I帧在插入点处开始从第二源插入视频。 例如，插入点可以指示视频流中的商业中断的开始，在这种情况下，第二个源提供商业插入到商业中断。 在商业存储在存储器中的情况下，可以将其第一帧（以编码顺序）存储为I帧。

公开(公告)号：US06925501B2

公开(公告)日：2005-08-02

申请号：US09836006

申请日：2001-04-17

申请人： Limin Wang ,  Ajay Luthra

发明人： Limin Wang ,  Ajay Luthra

IPC分类号： H03M7/30 ,  H04J3/00 ,  H04L12/20 ,  H04N7/26 ,  H04N21/2343 ,  H04N21/236 ,  H04N21/24 ,  H04N21/258 ,  H04N21/2662 ,  H04N21/6373 ,  G06F15/16

CPC分类号： H04N21/2405 ,  H04N19/156 ,  H04N19/20 ,  H04N19/40 ,  H04N21/234354 ,  H04N21/23439 ,  H04N21/236 ,  H04N21/25833 ,  H04N21/2662 ,  H04N21/6373

摘要： Methods and apparatus are provided to produce a plurality of different rate output bitstreams from a common input bit stream. Overhead data is extracted from the input bit stream. The input bit stream is partially decoded. Thereafter, the at least partially decoded bit stream is re-encoded at different rates, to produce multiple re-encoded bit streams having different rates. The overhead data is combined with each re-encoded bit stream, thereby providing multiple versions of said encoded bit stream at different rates.

摘要翻译： 提供方法和装置以从公共输入比特流产生多个不同速率的输出比特流。 从输入比特流中提取开销数据。 输入比特流被部分解码。 此后，至少部分解码的比特流以不同的速率重新编码，以产生具有不同速率的多个重新编码比特流。 开销数据与每个重新编码的比特流组合，从而以不同的速率提供所述编码比特流的多个版本。

公开(公告)号：US06904094B1

公开(公告)日：2005-06-07

申请号：US09665372

申请日：2000-09-20

申请人： Vincent Liu ,  Robert S. Nemiroff ,  Siu-Wai Wu ,  Ajay Luthra ,  Limin Wang

发明人： Vincent Liu ,  Robert S. Nemiroff ,  Siu-Wai Wu ,  Ajay Luthra ,  Limin Wang

IPC分类号： H04N7/26 ,  H04N7/50 ,  H04N7/12 ,  H04N11/02

CPC分类号： H04N19/40 ,  H04N19/156 ,  H04N19/42 ,  H04N19/436 ,  H04N19/61

摘要： An efficient processing system, such as for transcoding video data. In an embodiment that is suitable for single or multiple processor embodiments, a processing mode is set for each input video frame, e.g., as a full transcode mode, which uses motion compensation, a requantization mode, which avoids motion compensation, or a bypass mode. The processing mode selection is based on a number of processing cycles that are available to process a frame, and an expected processing requirement of the frame. The bypass or requantization modes are selected to avoid a buffer overflow of the processor.

摘要翻译： 一种高效的处理系统，例如用于对视频数据进行代码转换。 在适用于单个或多个处理器实施例的实施例中，为每个输入视频帧设置处理模式，例如，使用运动补偿的全代码转换模式，避免运动补偿的再量化模式或旁路模式 。 处理模式选择基于可用于处理帧的多个处理周期以及帧的预期处理要求。 选择旁路或再量化模式以避免处理器的缓冲区溢出。

公开(公告)号：US6167084A

公开(公告)日：2000-12-26

申请号：US141265

申请日：1998-08-27

申请人： Limin Wang ,  Ajay Luthra

发明人： Limin Wang ,  Ajay Luthra

IPC分类号： H04N7/32 ,  H04J3/00 ,  H04N7/08 ,  H04N7/081 ,  H04N7/50 ,  H04N21/2365 ,  H04N21/434 ,  H04N7/58

CPC分类号： H04N21/23655 ,  H04N19/105 ,  H04N19/115 ,  H04N19/126 ,  H04N19/137 ,  H04N19/14 ,  H04N19/152 ,  H04N19/162 ,  H04N19/172 ,  H04N19/177 ,  H04N19/40 ,  H04N19/61 ,  H04N19/70

摘要： The present invention relates to a method and apparatus for allocating bits in a statistical multiplexing system (stat mux). A statistical multiplexer (stat mux) accommodates both compressed and uncompressed video programs using transcoding and encoding, respectively. Hierarchical dynamic bit allocation is used, starting from a super GOP level, then to a super frame level, and then to the regular (individual) frame level. At each level, a target number of bits is determined. A target number of bits for a super frame, which is a collection of frames across all channels at a given frame instance, is adaptive and is able to address any combination of picture types. Frames of the same picture type for a program are generally assigned the same (or similar) number of bits. Relative program quality can be controlled using a program priority weighting factor. Additionally, constraints on target bit rates and minimum and maximum bit rates are provided.

摘要翻译： 本发明涉及用于在统计复用系统（stat mux）中分配比特的方法和装置。 统计复用器（stat mux）分别使用代码转换和编码来容纳压缩和未压缩的视频节目。 使用分级动态位分配，从超级GOP级开始，然后到超级帧级，然后到常规（单独）帧级。 在每个级别，确定目标位数。 作为在给定帧实例的所有信道上的帧的集合的超帧的目标位数是自适应的，并且能够解决图像类型的任何组合。 程序的相同图像类型的帧通常被分配相同（或类似的）位数。 可以使用程序优先权重因子来控制相对程序的质量。 此外，还提供了对目标比特率和最小和最大比特率的限制。