41
Naveen Thumpudi, Wei Ge Chen, Chao He: Reordering coefficients for waveform coding or decoding. Microsoft Corporation, Klarquist Sparkman, April 6, 2010: US07693709 (20 worldwide citation)

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 effi ...


42
Sanjeev Mehrotra, Wei ge Chen: Entropy coding by adapting coding between level and run-length/level modes. Microsoft Corporation, Klarquist Sparkman, October 7, 2008: US07433824 (20 worldwide citation)

An audio encoder performs adaptive entropy encoding of audio data. For example, an audio encoder switches between variable dimension vector Huffman coding of direct levels of quantized audio data and run-level coding of run lengths and levels of quantized audio data. The encoder can use, for example ...


43
Naveen Thumpudi, Wei Ge Chen, Chao He: Prediction of spectral coefficients in waveform coding and decoding. Microsoft Corporation, Klarquist Sparkman, March 23, 2010: US07684981 (19 worldwide citation)

Techniques and tools for prediction of spectral coefficients in encoding and decoding are described herein. For certain types and patterns of content, coefficient prediction exploits correlation between adjacent spectral coefficients, making subsequent entropy encoding more efficient. For example, a ...


44
Wei Ge Chen, Naveen Thumpudi, Ming Chieh Lee: Quantization matrices for jointly coded channels of audio. Microsoft Corporation, Klarquist Sparkman, December 26, 2006: US07155383 (19 worldwide citation)

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. For example, the audio encoder includes a multi-channel transformer operable to output multi-cha ...


45
Sanjeev Mehrotra, Wei Ge Chen: Entropy coding using escape codes to switch between plural code tables. Microsoft Corporation, Klarquist Sparkman, November 23, 2010: US07840403 (18 worldwide citation)

An audio encoder performs entropy encoding of audio data. For example, an audio encoder determines whether a first code table in a group of plural code tables contains a code representing a first vector. If it does, the code is used, and otherwise the escape code from the first code table is used an ...


46
Tian Wang, Hosam A Khalil, Kazuhito Koishida, Wei Ge Chen, Mu Han: Audio encoding and decoding with intra frames and adaptive forward error correction. Microsoft Corporation, Klarquist Sparkman, February 23, 2010: US07668712 (18 worldwide citation)

Various strategies for rate/quality control and loss resiliency in an audio codec are described. The various strategies can be used in combination or independently. For example, a real-time speech codec uses intra frame coding/decoding, adaptive multi-mode forward error correction [“FEC”], and rate/ ...


47
Tian Wang, Kazuhito Koishida, Hosam A Khalil, Xiaoqin Sun, Wei Ge Chen: Sub-band voice codec with multi-stage codebooks and redundant coding. Microsoft Corporation, Klarquist Sparkman, February 13, 2007: US07177804 (18 worldwide citation)

Techniques and tools related to coding and decoding of audio information are described. For example, redundant coded information for decoding a current frame includes signal history information associated with only a portion of a previous frame. As another example, redundant coded information for de ...


48
Naveen Thumpudi, Wei Ge Chen: Multi-channel audio encoding and decoding. Microsoft Corporation, Klarquist Sparkman, November 29, 2011: US08069050 (17 worldwide citation)

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-process ...


49
Wei ge Chen: Precompression extrapolation method. Microsoft Corporation, Klarquist Sparkman Campbell Leigh & Whinston, September 7, 1999: US05949919 (17 worldwide citation)

A precompression extrapolation method extrapolates image features of arbitrary configuration to a predefined configuration to facilitate compression of the image features. This extrapolation method allows compression of arbitrary image features to be performed in a conventional manner, such as discr ...


50
Wei Ge Chen, Naveen Thumpudi, Ming Chieh Lee: Quantization matrices using normalized-block pattern of digital audio. Microsoft Corporation, Klarquist Sparkman, July 24, 2007: US07249016 (16 worldwide citation)

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 separat ...