公开(公告)号：US20090248424A1

公开(公告)日：2009-10-01

申请号：US12055223

申请日：2008-03-25

申请人： Kazuhito Koishida ,  Sanjeev Mehrotra ,  Radhika Jandhyala

发明人： Kazuhito Koishida ,  Sanjeev Mehrotra ,  Radhika Jandhyala

IPC分类号： G10L21/04

CPC分类号： G10L19/24 ,  G10L19/0017 ,  G10L19/008 ,  G10L19/0212

摘要： A scalable audio codec encodes an input audio signal as a base layer at a high compression ratio and one or more residual signals as an enhancement layer of a compressed bitstream, which permits a lossless or near lossless reconstruction of the input audio signal at decoding. The scalable audio codec uses perceptual transform coding to encode the base layer. The residual is calculated in a transform domain, which includes a frequency and possibly also multi-channel transform of the input audio. For lossless reconstruction, the frequency and multi-channel transforms are reversible.

摘要翻译： 可扩展音频编解码器将输入音频信号编码为高压缩比的基本层和作为压缩比特流的增强层的一个或多个残留信号，其允许在解码时对输入音频信号进行无损或近无损重建。 可扩展音频编解码器使用感知变换编码来对基本层进行编码。 在变换域中计算残差，其包括输入音频的频率和可能的多通道变换。 对于无损重建，频率和多通道变换是可逆的。

公开(公告)号：US20090210222A1

公开(公告)日：2009-08-20

申请号：US12032119

申请日：2008-02-15

申请人： Sanjeev Mehrotra ,  Hui Gao ,  Kazuhito Kioshida ,  Chao He

发明人： Sanjeev Mehrotra ,  Hui Gao ,  Kazuhito Kioshida ,  Chao He

IPC分类号： G10L19/00

CPC分类号： G10L19/008 ,  G10L19/0204

摘要： Multi-channel hole-filling for audio compression is disclosed. Channel dependency groups (CDGs) are explicitly extracted based on channel transform information. Holes are detected within each CDG for each bark, and a CDG hole is identified as requiring filling as a particular section of frequency bandwidth larger than a predetermined hole bandwidth threshold and with all zero-value coefficients in all channels after quantizing. Bark weights are adjusted by multiplying the original bark weights with one calculated scalar so as to remove each detected CDG hole.

摘要翻译： 公开了用于音频压缩的多通道孔填充。 基于信道变换信息明确提取频道依赖组（CDG）。 在每个CDG内为每个树皮检测孔，并且将CDG孔识别为需要填充作为大于预定孔带宽阈值的频率带宽的特定部分，并且在量化之后具有所有通道中的所有零值系数。 通过将原始树皮重量乘以一个计算标量来调整树皮重量，以便去除每个检测到的CDG孔。

公开(公告)号：US20090083046A1

公开(公告)日：2009-03-26

申请号：US12324689

申请日：2008-11-26

申请人： Sanjeev Mehrotra ,  Wei-Ge Chen

发明人： Sanjeev Mehrotra ,  Wei-Ge Chen

IPC分类号： G10L19/00

CPC分类号： G10L19/0208 ,  G10L19/0204 ,  G10L19/035

摘要： Traditional audio encoders may conserve coding bit-rate by encoding fewer than all spectral coefficients, which can produce a blurry low-pass sound in the reconstruction. An audio encoder using wide-sense perceptual similarity improves the quality by encoding a perceptually similar version of the omitted spectral coefficients, represented as a scaled version of already coded spectrum. The omitted spectral coefficients are divided into a number of sub-bands. The sub-bands are encoded as two parameters: a scale factor, which may represent the energy in the band; and a shape parameter, which may represent a shape of the band. The shape parameter may be in the form of a motion vector pointing to a portion of the already coded spectrum, an index to a spectral shape in a fixed code-book, or a random noise vector. The encoding thus efficiently represents a scaled version of a similarly shaped portion of spectrum to be copied at decoding.

摘要翻译： 传统的音频编码器可以通过编码少于所有频谱系数来节省编码比特率，这可以在重建中产生模糊的低通声音。 使用广义感知相似性的音频编码器通过编码被忽略的频谱系数的感知相似版本来提高质量，表示为已编码频谱的缩放版本。 省略的频谱系数被划分为多个子带。 子带被编码为两个参数：比例因子，其可以表示频带中的能量; 以及形状参数，其可以表示带的形状。 形状参数可以是指向已编码频谱的一部分的运动矢量的形式，固定码本中的频谱形状的索引或随机噪声向量。 因此，编码有效地表示在解码时要复制的类似形状的频谱部分的缩放版本。

公开(公告)号：US07460990B2

公开(公告)日：2008-12-02

申请号：US10882801

申请日：2004-06-29

申请人： Sanjeev Mehrotra ,  Wei-Ge Chen

发明人： Sanjeev Mehrotra ,  Wei-Ge Chen

IPC分类号： G10L11/04

CPC分类号： G10L19/0208 ,  G10L19/0204 ,  G10L19/035

摘要： Traditional audio encoders may conserve coding bit-rate by encoding fewer than all spectral coefficients, which can produce a blurry low-pass sound in the reconstruction. An audio encoder using wide-sense perceptual similarity improves the quality by encoding a perceptually similar version of the omitted spectral coefficients, represented as a scaled version of already coded spectrum. The omitted spectral coefficients are divided into a number of sub-bands. The sub-bands are encoded as two parameters: a scale factor, which may represent the energy in the band; and a shape parameter, which may represent a shape of the band. The shape parameter may be in the form of a motion vector pointing to a portion of the already coded spectrum, an index to a spectral shape in a fixed code-book, or a random noise vector. The encoding thus efficiently represents a scaled version of a similarly shaped portion of spectrum to be copied at decoding.

摘要翻译： 传统的音频编码器可以通过编码少于所有频谱系数来节省编码比特率，这可以在重建中产生模糊的低通声音。 使用广义感知相似性的音频编码器通过编码被忽略的频谱系数的感知相似版本来提高质量，表示为已编码频谱的缩放版本。 省略的频谱系数被划分为多个子带。 子带被编码为两个参数：比例因子，其可以表示频带中的能量; 以及形状参数，其可以表示带的形状。 形状参数可以是指向已编码频谱的一部分的运动矢量的形式，固定码本中的频谱形状的索引或随机噪声向量。 因此，编码有效地表示在解码时要复制的类似形状的频谱部分的缩放版本。

公开(公告)号：US07224731B2

公开(公告)日：2007-05-29

申请号：US10186473

申请日：2002-06-28

申请人： Sanjeev Mehrotra

发明人： Sanjeev Mehrotra

IPC分类号： H04N7/12 ,  G06K9/36

CPC分类号： H04N5/145 ,  H04N19/105 ,  H04N19/132 ,  H04N19/139 ,  H04N19/147 ,  H04N19/152 ,  H04N19/17 ,  H04N19/172 ,  H04N19/176 ,  H04N19/18 ,  H04N19/51 ,  H04N19/53 ,  H04N19/557 ,  H04N19/56 ,  H04N19/59 ,  H04N19/60 ,  H04N19/61 ,  H04N19/91

摘要： The present invention relates to motion estimation and compensation. For example, a screen capture encoder performs motion estimation that is adapted to screen capture video in various respects. For example, the motion estimation uses a distortion measure based upon the count of equal/unequal pixels in two regions, sub-samples the distortion measure to speed up motion estimation, and/or uses a search pattern that prioritizes types of motion common in screen capture video. Or, a screen capture decoder performs motion compensation that is adapted to screen capture video in various respects. For example, the decoder performs the motion compensation for pixels with different values at corresponding locations in a current frame and a reference frame, but not for all pixels of the current frame. Alternatively, an encoder/decoder performs the motion estimation/compensation to compress/decompress other kinds of content.

摘要翻译： 本发明涉及运动估计和补偿。 例如，屏幕捕获编码器执行适于在各个方面屏幕捕获视频的运动估计。 例如，运动估计使用基于两个区域中的相等/不等像素的计数的失真度量，对失真测量进行子采样以加速运动估计，和/或使用对屏幕中共同的运动类型进行优先排序的搜索模式 捕获视频 或者，屏幕捕获解码器执行适于在各个方面屏幕捕获视频的运动补偿。 例如，解码器对当前帧和参考帧中的相应位置处的具有不同值的像素执行运动补偿，但不对当前帧的所有像素执行运动补偿。 或者，编码器/解码器执行运动估计/补偿来压缩/解压缩其他种类的内容。

公开(公告)号：US07072512B2

公开(公告)日：2006-07-04

申请号：US10202223

申请日：2002-07-23

申请人： Sanjeev Mehrotra

发明人： Sanjeev Mehrotra

IPC分类号： G06K9/34

CPC分类号： H04N19/12 ,  G06T9/00 ,  H04N19/14 ,  H04N19/17 ,  H04N19/27 ,  H04N19/85

摘要： For encoding of mixed-content images containing palettized and continuous-tone content, continuous tone content regions in the image are detected and separated. Continuous tone content segmentation classifies pixels as continuous tone content by counting a number of unique pixel values within a pixel neighborhood. Pixels whose count exceeds a threshold are classified as continuous tone content. The technique further scans the image for regions of high continuous tone pixel density. The segmented continuous-tone and palettized content can be encoded separately for efficient compression, and then reassembled at decompression.

摘要翻译： 对于包含调色和连续色调内容的混合内容图像的编码，检测和分离图像中的连续色调内容区域。 连续色调内容分割通过对像素邻域内的唯一像素值进行计数来将像素分类为连续色调内容。 计数超过阈值的像素被分类为连续色调内容。 该技术进一步扫描图像以获得高连续色调像素密度的区域。 分段的连续色调和调色的内容可以单独编码以进行有效的压缩，然后在解压缩时重新组合。

公开(公告)号：US06980695B2

公开(公告)日：2005-12-27

申请号：US10186481

申请日：2002-06-28

申请人： Sanjeev Mehrotra

发明人： Sanjeev Mehrotra

IPC分类号： H04N7/26 ,  H04N7/50 ,  G06K9/36

CPC分类号： H04N19/17 ,  H04N19/124 ,  H04N19/152 ,  H04N19/30 ,  H04N19/46 ,  H04N19/61

摘要： The present invention relates to regulating the quality and/or bitrate of content within mixed content video when the video is compressed subject to a bitrate constraint. For example, a screen capture encoder encodes palletized content within a frame of screen capture video. Subject to an overall bitrate constraint, the encoder then allocates bits for continuous tone content within the frame. By controlling the allocation of bits used to encode the continuous tone content, the encoder regulates bitrate for the continuous tone content. This in turn can allow the encoder to regulate spatial quality and/or overall temporal quality for the video. In one scenario, for screen capture video encoded to a (relatively) constant overall bitrate, the screen capture encoder reduces the bitrate (and quality) of the continuous tone content, instead spending bits to increase the overall frame rate of the video.

摘要翻译： 本发明涉及当视频被比特率约束压缩时，调节混合内容视频内容的质量和/或比特率。 例如，屏幕捕获编码器在屏幕捕获视频的帧内编码码垛内容。 在总体比特率约束的情况下，编码器然后为帧内的连续色调内容分配比特。 通过控制用于编码连续色调内容的位的分配，编码器调节连续色调内容的比特率。 这又可以允许编码器调节视频的空间质量和/或整体时间质量。 在一种情况下，为了编码为（相对）恒定的总比特率的屏幕捕获视频，屏幕捕获编码器降低连续色调内容的比特率（和质量），而是花费比特来增加视频的总体帧速率。

公开(公告)号：US20050249211A1

公开(公告)日：2005-11-10

申请号：US11177258

申请日：2005-07-08

申请人： Philip Chou ,  Albert Wang ,  Sanjeev Mehrotra ,  Alexander Mohr

发明人： Philip Chou ,  Albert Wang ,  Sanjeev Mehrotra ,  Alexander Mohr

IPC分类号： H04L1/00 ,  H04L1/06 ,  H04L1/08 ,  G06K5/04 ,  H04J3/24 ,  H04L12/28 ,  H04L12/56

CPC分类号： H04L1/007 ,  H04L1/0009 ,  H04L1/0017 ,  H04L1/06 ,  H04L1/1812 ,  H04L2001/0093

摘要： A system and method for correcting errors and losses occurring during a receiver-driven layered multicast (RLM) of real-time media over a heterogeneous packet network such as the Internet. This is accomplished by augmenting RLM with one or more layers of error correction information. This allows each receiver to separately optimize the quality of received audio and video information by subscribing to at least one error correction layer. Ideally, each source layer in a RLM would have one or more multicasted error correction data streams (i.e., layers) associated therewith. Each of the error correction layers would contain information that can be used to replace lost packets from the associated source layer. More than one error correction layer is proposed as some of the error correction packets contained in the data stream needed to replace the packets lost in the associated source stream may themselves be lost in transmission. A preferred process for generating the error correction streams involves the use of a unique adaptation of the Forward Error Correction (FEC) techniques. This process encodes the transmission data using a linear transform which adds redundant elements. The redundancy permits losses to be corrected because any of the original data elements can be derived from any of the encoded elements. Thus, as long as enough of the encoded data elements are received so as to equal the number of the original data elements, it is possible to derive all the original elements.

摘要翻译： 一种用于在异构分组网络（例如因特网）下校正在实时媒体的接收机驱动分层多播（RLM）期间发生的错误和损失的系统和方法。 这是通过用一层或多层纠错信息增强RLM来实现的。 这允许每个接收机通过订阅至少一个纠错层来分别优化所接收的音频和视频信息的质量。 理想地，RLM中的每个源层将具有与其相关联的一个或多个多播的纠错数据流（即，层）。 每个纠错层将包含可用于替换相关源层丢失的分组的信息。 提出了多于一个纠错层，因为包含在替换相关源流中丢失的分组所需的数据流中的一些纠错分组本身可能在传输中丢失。 用于产生纠错流的优选过程涉及使用前向纠错（FEC）技术的唯一适配。 该过程使用添加冗余元素的线性变换对传输数据进行编码。 冗余允许修正损失，因为任何原始数据元素可以从任何编码元素导出。 因此，只要接收到足够的编码数据元素以便等于原始数据元素的数量，就有可能导出所有的原始元素。

公开(公告)号：US06584226B1

公开(公告)日：2003-06-24

申请号：US08819587

申请日：1997-03-14

申请人： Navin Chaddha ,  Albert Wang ,  Sanjeev Mehrotra

发明人： Navin Chaddha ,  Albert Wang ,  Sanjeev Mehrotra

IPC分类号： G06K946

CPC分类号： G06T9/008 ,  G06T7/223 ,  G06T2207/10016 ,  H04N19/503 ,  H04N19/61 ,  H04N19/91 ,  H04N19/94 ,  H04N19/96

摘要： Methods and apparatus for processing video data that is divided into frames are presented. In one aspect, this relates to a method for processing video data that is divided into frames. The video data includes a current frame, which has an associated current macroblock, and an adjacent frame, which also has an associated macroblock. The method for processing video data involves obtaining an uncompressed current block that is a part of the current macroblock and an adjacent block that is part of the adjacent macroblock, and calculating a distance between the uncompressed current block and the adjacent block. It is determined whether the distance between the uncompressed current block and the adjacent block is acceptable. If the distance is unacceptable, then the motion between the uncompressed current block and the adjacent block is estimated, and the uncompressed current block is adaptively compressed.

摘要翻译： 提出了分割为帧的视频数据处理方法和装置。 一方面，这涉及一种用于处理被划分成帧的视频数据的方法。 视频数据包括具有相关联的当前宏块的当前帧以及也具有相关宏块的相邻帧。 用于处理视频数据的方法涉及获得作为当前宏块的一部分的未压缩的当前块和作为相邻宏块的一部分的相邻块，以及计算未压缩的当前块与相邻块之间的距离。 确定未压缩的当前块与相邻块之间的距离是否可接受。 如果距离不可接受，则估计未压缩的当前块和相邻块之间的运动，并且自压压缩未压缩的当前块。