Toshiyuki Nomura

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This paper proposes a flexible CELP speech coder with bitrate and bandwidth scalabilities for multimedia applications. The coder is based on multi-pulse-based CELP coding and consists of a bitrate scalable base-band coder and a bandwidth extension tool. The bitrate scalable base-band CELP coder employs multi-stage exci-tation coding based on an(More)
Presented here is MPEG-2 AAC LC Profile encoder software for an Intel Pentium III processor. MDCT and quantization processing are accelerated by the use of SIMD instructions. Psycho-acoustic analysis in the MDCT domain makes the use of FFTs unnecessary. Better sound quality is provided by greater efficiency in quantization processing and Huffman coding. All(More)
Binaural cue coding, which is a representing low bit-rate coding of multichannel audio, generates large distortion when the audio data have complex spatial image, such as symphony. Such distortion caused by the low frequency resolution of spatial information because BCC quantizes the parameters of localization. In this paper we propose a new coding(More)
This paper proposes a speech codec based on the Multi-Pulse based CELP (MP-CELP) coding and a convolutional coding algorithms for the ETSI Adaptive Multi-Rate (AMR) standard. The codec operates at several speech coding rates, maintaining a fixed gross rate including speech and channel coding for the Full-Rate (FR) and Half-Rate (HR) channel modes. MP-CELP(More)
We propose methods to analyze and control source localization of stereo audio signals using blind source separation (BSS) based on independent component analysis (ICA). Although an inverse system of separation compensates distortion caused by ICA as reconstruction of stereo spatial characteristics, this technique is insufficient to analyze localization(More)