公开(公告)号：US09848209B2

公开(公告)日：2017-12-19

申请号：US12061567

申请日：2008-04-02

申请人： Gang Ji ,  Yongjun Wu ,  Florin Folta ,  Naveen Thumpudi

发明人： Gang Ji ,  Yongjun Wu ,  Florin Folta ,  Naveen Thumpudi

IPC分类号： H04N19/46 ,  H04N19/895 ,  H04N19/176 ,  H04N19/134 ,  H04N19/61 ,  H04N19/18

CPC分类号： H04N19/895 ,  H04N19/134 ,  H04N19/176 ,  H04N19/18 ,  H04N19/46 ,  H04N19/61

摘要： A decoder which can detect errors in MPEG-2 coefficient blocks can identify syntactically-correct blocks which have out-of-bounds coefficients. The decoder computes coefficient bounds based on quantization scalers and quantization matrices and compares these to coefficient blocks during decoding; if a block has out-of-bounds coefficients, concealment is performed on the block. In a decoder implemented all in software, coefficient bounds checking is performed on iDCT coefficients against upper and lower bounds in a spatial domain. In a decoder which performs iDCT in hardware, DCT coefficients are compared to an upper energy bound.

公开(公告)号：US08255230B2

公开(公告)日：2012-08-28

申请号：US13326315

申请日：2011-12-14

申请人： Naveen Thumpudi ,  Wei-Ge Chen

发明人： Naveen Thumpudi ,  Wei-Ge Chen

IPC分类号： G10L19/00 ,  G10L21/00 ,  G10L21/04

CPC分类号： G10L19/00 ,  G10L19/008 ,  G10L19/0212

摘要： An audio encoder and decoder use architectures and techniques that improve the efficiency of multi-channel audio coding and decoding. The described strategies include various techniques and tools, which can be used in combination or independently. For example, an audio encoder performs a pre-processing multi-channel transform on multi-channel audio data, varying the transform so as to control quality. The encoder groups multiple windows from different channels into one or more tiles and outputs tile configuration information, which allows the encoder to isolate transients that appear in a particular channel with small windows, but use large windows in other channels. Using a variety of techniques, the encoder performs flexible multi-channel transforms that effectively take advantage of inter-channel correlation. An audio decoder performs corresponding processing and decoding. In addition, the decoder performs a post-processing multi-channel transform for any of multiple different purposes.

摘要翻译： 音频编码器和解码器使用提高多声道音频编码和解码效率的架构和技术。 所描述的策略包括可以组合或独立使用的各种技术和工具。 例如，音频编码器对多声道音频数据执行预处理多声道变换，改变变换以便控制质量。 编码器将来自不同通道的多个窗口分组成一个或多个瓦片并输出瓦片配置信息，这允许编码器隔离出具有小窗口的特定通道中的瞬态，但在其他通道中使用大窗口。 使用各种技术，编码器执行灵活的多通道变换，有效利用信道间相关性。 音频解码器执行相应的处理和解码。 此外，解码器对于多个不同目的中的任一个执行后处理多信道变换。

公开(公告)号：US08189666B2

公开(公告)日：2012-05-29

申请号：US12364325

申请日：2009-02-02

申请人： Yongjun Wu ,  Naveen Thumpudi ,  Kim-chyan Gan

发明人： Yongjun Wu ,  Naveen Thumpudi ,  Kim-chyan Gan

IPC分类号： H04N7/36 ,  H04N11/02

CPC分类号： H04N19/44 ,  H04N19/102 ,  H04N19/159 ,  H04N19/176 ,  H04N19/46 ,  H04N19/513 ,  H04N19/61 ,  H04N19/70

摘要： Video decoding innovations for using local picture identifiers and computing co-located information are described. In one aspect, a decoder identifies reference pictures in a reference picture list of a temporal direct prediction mode macroblock that match reference pictures used by a co-located macroblock using local picture identifiers. In another aspect, a decoder determines whether reference pictures used by blocks are the same by comparing local picture identifiers during calculation of boundary strength. In yet another aspect, a decoder determines a picture type of a picture and based on the picture type selectively skips or simplifies computation of co-located information for use in reconstructing direct prediction mode macroblocks outside the picture.

摘要翻译： 描述了使用本地图片标识符和计算共址信息的视频解码创新。 在一个方面，解码器识别与使用本地图像标识符的同位置宏块使用的参考图片相匹配的时间直接预测模式宏块的参考图片列表中的参考图片。 在另一方面，解码器通过在计算边界强度期间比较局部图像标识符来确定块使用的参考图片是否相同。 在另一方面，解码器确定图像的图像类型并且基于图像类型有选择地跳过或简化用于重建图像外部的直接预测模式宏块的共位信息的计算。

公开(公告)号：US20120035941A1

公开(公告)日：2012-02-09

申请号：US13276163

申请日：2011-10-18

申请人： Naveen Thumpudi ,  Wei-Ge Chen

发明人： Naveen Thumpudi ,  Wei-Ge Chen

IPC分类号： G10L19/00

CPC分类号： G10L19/032 ,  G10L19/008

摘要： An audio encoder and decoder use architectures and techniques that improve the efficiency of quantization (e.g., weighting) and inverse quantization (e.g., inverse weighting) in audio coding and decoding. The described strategies include various techniques and tools, which can be used in combination or independently. For example, an audio encoder quantizes audio data in multiple channels, applying multiple channel-specific quantizer step modifiers, which give the encoder more control over balancing reconstruction quality between channels. The encoder also applies multiple quantization matrices and varies the resolution of the quantization matrices, which allows the encoder to use more resolution if overall quality is good and use less resolution if overall quality is poor. Finally, the encoder compresses one or more quantization matrices using temporal prediction to reduce the bitrate associated with the quantization matrices. An audio decoder performs corresponding inverse processing and decoding.

摘要翻译： 音频编码器和解码器使用在音频编码和解码中提高量化（例如，加权）和逆量化（例如，反加权）的效率的架构和技术。 所描述的策略包括可以组合或独立使用的各种技术和工具。 例如，音频编码器对多个信道中的音频数据进行量化，应用多个信道专用量化器步进修改器，这使得编码器更多地控制平衡信道之间的重建质量。 编码器还应用多个量化矩阵并改变量化矩阵的分辨率，这允许编码器在整体质量好的情况下使用更高的分辨率，并且如果整体质量差，则使用较小的分辨率。 最后，编码器使用时间预测来压缩一个或多个量化矩阵，以减少与量化矩阵相关联的比特率。 音频解码器执行相应的反向处理和解码。

公开(公告)号：US07548855B2

公开(公告)日：2009-06-16

申请号：US11475301

申请日：2006-06-26

申请人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

发明人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

IPC分类号： G10L19/00

CPC分类号： G10L25/69

摘要： An audio processing tool measures the quality of reconstructed audio data. For example, an audio encoder measures the quality of a block of reconstructed frequency coefficient data in a quantization loop. The invention includes several techniques and tools, which can be used in combination or separately. First, before measuring quality, the tool normalizes the block to account for variation in block sizes. Second, for the quality measurement, the tool processes the reconstructed data by critical bands, which can differ from the quantization bands used to compress the data. Third, the tool accounts for the masking effect of the reconstructed data, not just the masking effect of the original data. Fourth, the tool band weights the quality measurement, which can be used to account for noise substitution or band truncation. Finally, the tool changes quality measurement techniques depending on the channel coding mode.

摘要翻译： 音频处理工具测量重建音频数据的质量。 例如，音频编码器在量化循环中测量重构频率系数数据块的质量。 本发明包括可以组合或分开使用的几种技术和工具。 首先，在测量质量之前，刀具将程序段归一化以考虑块大小的变化。 第二，对于质量测量，该工具通过临界频带处理重构数据，这可能与用于压缩数据的量化频带不同。 第三，该工具解决了重构数据的掩蔽效应，而不仅仅是原始数据的掩蔽效应。 第四，工具带对质量测量进行加权，可用于考虑噪声替代或带截断。 最后，该工具根据信道编码模式改变质量测量技术。

公开(公告)号：US07299175B2

公开(公告)日：2007-11-20

申请号：US11067018

申请日：2005-02-24

申请人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

发明人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

IPC分类号： G10L19/14

CPC分类号： G10L19/24 ,  G10L19/002

摘要： An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. First, an encoder regulates quantization using quality, minimum bit count, and maximum bit count parameters. Second, an encoder regulates quantization using a noise measure that indicates reliability of a complexity measure. Third, an encoder normalizes a control parameter value according to block size for a variable-size block. Fourth, an encoder uses a bit-count control loop de-linked from a quality control loop. Fifth, an encoder addresses non-monotonicity of quality measurement as a function of quantization level when selecting a quantization level. Sixth, an encoder uses particular interpolation rules to find a quantization level in a quality or bit-count control loop. Seventh, an encoder filters a control parameter value to smooth quality. Eighth, an encoder corrects model bias by adjusting a control parameter value in view of current buffer fullness.

摘要翻译： 音频编码器通过控制策略来调节质量和比特率。 该策略包括几个功能。 首先，编码器使用质量，最小位计数和最大位计数参数来调节量化。 第二，编码器使用指示复杂性度量的可靠性的噪声测量来调节量化。 第三，编码器根据可变大小块的块大小对控制参数值进行归一化。 第四，编码器使用从质量控制环路去链接的位计数控制环路。 第五，当选择量化级别时，编码器将质量测量的非单调性作为量化级别的函数。 第六，编码器使用特定的内插规则来在质量或位计数控制环路中找到量化级别。 第七，编码器过滤控制参数值以平滑质量。 第八，编码器通过根据当前缓冲区饱和度调整控制参数值来校正模型偏差。

公开(公告)号：US20070185706A1

公开(公告)日：2007-08-09

申请号：US11737072

申请日：2007-04-18

申请人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

发明人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

IPC分类号： G10L19/00

CPC分类号： G10L19/008 ,  G10L19/002 ,  G10L19/02

摘要： An audio encoder implements multi-channel coding decision, band truncation, multi-channel rematrixing, and header reduction techniques to improve quality and coding efficiency. In the multi-channel coding decision technique, the audio encoder dynamically selects between joint and independent coding of a multi-channel audio signal via an open-loop decision based upon (a) energy separation between the coding channels, and (b) the disparity between excitation patterns of the separate input channels. In the band truncation technique, the audio encoder performs open-loop band truncation at a cut-off frequency based on a target perceptual quality measure. In multi-channel rematrixing technique, the audio encoder suppresses certain coefficients of a difference channel by scaling according to a scale factor, which is based on current average levels of perceptual quality, current rate control buffer fullness, coding mode, and the amount of channel separation in the source. In the header reduction technique, the audio encoder selectively modifies the quantization step size of zeroed quantization bands so as to encode in fewer frame header bits.

摘要翻译： 音频编码器实现多信道编码决策，频带截断，多信道重叠矩阵和头缩减技术，以提高质量和编码效率。 在多信道编​​码决策技术中，音频编码器通过基于（a）编码信道之间的能量分离的开环决策，动态地在多声道音频信号的联合和独立编码之间进行选择，和（b）视差 在单独的输入通道的激励模式之间。 在频带截断技术中，音频编码器基于目标感知质量测量，以截止频率执行开环频带截断。 在多声道再现矩阵技术中，音频编码器根据当前平均感知质量水平，当前速率控制缓冲器充满度，编码模式和频道数量的比例因子按比例缩放差分信道的某些系数。 在源头分离。 在标题缩小技术中，音频编码器有选择地修改置零的量化频带的量化步长，以便以更少的帧头位编码。

公开(公告)号：US20070016406A1

公开(公告)日：2007-01-18

申请号：US11183297

申请日：2005-07-15

申请人： Naveen Thumpudi ,  Wei-Ge Chen ,  Chao He

发明人： Naveen Thumpudi ,  Wei-Ge Chen ,  Chao He

IPC分类号： G10L21/00

CPC分类号： G10L19/022 ,  G10L19/008 ,  G10L19/0212

摘要： Techniques and tools for reordering of spectral coefficients in encoding and decoding are described herein. For certain types and patterns of content, coefficient reordering reduces redundancy that is due to periodic patterns in the spectral coefficients, making subsequent entropy encoding more efficient. For example, an audio encoder receives spectral coefficients logically organized along one dimension such as frequency, reorders at least some of the spectral coefficients, and entropy encodes the spectral coefficients after the reordering. Or, an audio decoder receives entropy encoded information for such spectral coefficients, entropy decodes the information, and reverses reordering of at least some of the spectral coefficients.

摘要翻译： 本文描述了用于在编码和解码中重新排序频谱系数的技术和工具。 对于某些类型和内容模式，系数重新排序减少了由于频谱系数中的周期性模式造成的冗余，使后续的熵编码更有效率。 例如，音频编码器接收沿着诸如频率的一个维度逻辑组织的频谱系数，对至少一些频谱系数进行重新排序，以及对重新排序之后的频谱系数进行熵编码。 或者，音频解码器接收这种频谱系数的熵编码信息，熵解码信息，并且反转至少一些频谱系数的重新排序。

公开(公告)号：US20050015259A1

公开(公告)日：2005-01-20

申请号：US10622822

申请日：2003-07-18

申请人： Naveen Thumpudi ,  Wei-Ge Chen

发明人： Naveen Thumpudi ,  Wei-Ge Chen

IPC分类号： G10L19/14 ,  G10L19/00

CPC分类号： G10L19/24

摘要： CBR control strategies provide constant or relatively constant bitrate output with variable quality. The control strategies include various techniques and tools, which can be used in combination or independently. For example, an audio encoder uses a trellis in two-pass or delayed-decision CBR encoding. The trellis nodes are states derived by quantizing buffer fullness values. The transitions between nodes of a previous stage and nodes of a current stage depend on encoding a current chunk of audio at different quality levels. When pruning the trellis, the encoder uses a cost function that considers smoothness in quality as well as quality in absolute terms. The encoder may store compressed data at different quality levels, then output the compressed data after simplification of the trellis to a suitable point. If the two-pass or delayed-decision CBR encoding fails, the encoder uses one-pass CBR encoding for the sequence or part of the sequence.

摘要翻译： CBR控制策略提供恒定或相对恒定的可变质量的比特率输出。 控制策略包括可以组合或独立使用的各种技术和工具。 例如，音频编码器使用双向或延迟决定CBR编码中的网格。 网格节点是通过量化缓冲区满度值得到的状态。 先前阶段的节点和当前阶段的节点之间的转换取决于以不同质量级别编码当前音频块。 当修剪格子时，编码器使用考虑质量平滑度和绝对质量的成本函数。 编码器可以存储不同质量级别的压缩数据，然后在将格架简化为合适点之后输出压缩数据。 如果双通或延迟决策CBR编码失败，则编码器对序列或序列的一部分使用一次CBR编码。

公开(公告)号：US08428943B2

公开(公告)日：2013-04-23

申请号：US13046530

申请日：2011-03-11

申请人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

发明人： Wei-Ge Chen ,  Naveen Thumpudi ,  Ming-Chieh Lee

IPC分类号： G10L19/02 ,  G10L19/04

CPC分类号： G10L19/008 ,  G10L19/02 ,  G10L19/0204

摘要： Quantization matrices facilitate digital audio encoding and decoding. An audio encoder generates and compresses quantization matrices; an audio decoder decompresses and applies the quantization matrices. The invention includes several techniques and tools, which can be used in combination or separately. For example, the audio encoder can generate quantization matrices from critical band patterns for blocks of audio data. The encoder can compute the quantization matrices directly from the critical band patterns, which can be computed from the same audio data that is being compressed. The audio encoder/decoder can use different modes for generating/applying quantization matrices depending on the coding channel mode of multi-channel audio data. The audio encoder/decoder can use different compression/decompression modes for the quantization matrices, including a parametric compression/decompression mode.