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Adaptive Multi-Rate audio codec

About: Adaptive Multi-Rate audio codec is a research topic. Over the lifetime, 1467 publications have been published within this topic receiving 19736 citations. The topic is also known as: AMR & Adaptive Multi-Rate.


Papers
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Proceedings ArticleDOI
06 Sep 2009
TL;DR: The highband information is embedded into the pitch delay data of the AMR codec using an extended quantization-based method that achieves increased embedding capacity and higher perceived sound quality than the previous steganographic method.
Abstract: This paper proposes a bandwidth extension (BWE) method for the AMR narrow-band speech codec using steganography, which is called steganographic BWE herein. The highband information is embedded into the pitch delay data of the AMR codec using an extended quantization-based method that achieves increased embedding capacity and higher perceived sound quality than the previous steganographic method. The target bit-rate mode is below 7 kbps, the level below which the previous steganographic BWE method did not maintain adequate sound quality. The sound quality of the steganographic BWE speech signals decoded from the embedded bitstream is comparable to that of the wide-band speech signals of the AMRWB codec at a bit rate of less than 6.7 kbps, with only a slight degradation in the quality relative to speech signals decoded from the same bitstream by the legacy AMR decoder.

12 citations

Proceedings ArticleDOI
01 May 2005
TL;DR: A new technique for coding stereo video sequences based on H.264 video codec that exploits disparity and worldline correlation in addition to the advance compression techniques inherited by the H. 264 standard to achieve a higher video quality especially in the low bit rates.
Abstract: Due to the provision of a more natural representation of a scene in the form of left and right eye views, a stereoscopic imaging system provides a more effective method for image/video display. Unfortunately the vast amount of information that needs to be transmitted/stored to represent a stereo image pair/video sequence, has so far hindered its use in commercial applications. However, by properly exploiting the spatial, temporal and binocular redundancy, a stereo image pair or a sequence could be compressed and transmitted through a single monocular channel's bandwidth without unduly sacrificing the perceived stereoscopic image quality. In this paper, we present a new technique for coding stereo video sequences based on H.264 video codec. The proposed codec exploits disparity and worldline correlation in addition to the advance compression techniques inherited by the H.264 standard to achieve a higher video quality especially in the low bit rates. We compare the performance of the proposed CODEC with a DCT-based, modified MPEG-2 stereo video CODEC and ZTE based stereo video CODEC. We show that the proposed CODEC outperforms the benchmark CODECs in coding both main and auxiliary streams by up to 9.0 dB PSNR gain

12 citations

Proceedings ArticleDOI
26 May 2013
TL;DR: A new method for wideband speech transmission is proposed which is fully backwards compatible with narrowband telephone systems, where a pitch-scaled version of the higher speech frequencies is inserted into the previously “unused” 3.4 - 4 kHz frequency range.
Abstract: A new method for wideband speech transmission is proposed which is fully backwards compatible with narrowband telephone systems. For this purpose, a pitch-scaled version of the higher speech frequencies (4 - 6.4 kHz) is inserted into the previously “unused” 3.4 - 4 kHz frequency range of standard telephone speech. This operation is reverted at the decoder side. A consistently good wideband speech quality can be achieved, even after transmission over common codecs and codec tandems. The quality impact on the narrowband part of the signal is insignificant.

12 citations

Journal ArticleDOI
H.T. How1, T. H. Liew1, E.L. Kuan, Lie-Liang Yang, Lajos Hanzo 
TL;DR: A burst-by-burst (BbB) adaptive speech transceiver is proposed, which can drop its source coding rate and speech quality under transceiver control in order to invoke a more error resilient modem mode among less favorable channel conditions.
Abstract: A burst-by-burst (BbB) adaptive speech transceiver is proposed, which can drop its source coding rate and speech quality under transceiver control in order to invoke a more error resilient modem mode among less favorable channel conditions. The adaptive multirate (AMR) speech codec is operated at bit rates of 4.75 and 10.2 kb/s and combined with source sensitivity-matched redundant residue number system (RRNS) based channel codes. BbB adaptive joint detection aided code division multiple access is used for supporting the dual rate speech codec. Both the objective and subjective speech quality assessments favored the proposed BbB adaptive transceiver.

12 citations

Patent
01 Sep 2010
TL;DR: In this paper, a transceiver consisting of a codec, a microcontroller, and a radio is used to receive the first digital audio signal from the codec and packetize it into a first packet for transmission over a TCP/IP network.
Abstract: A transceiver including, a codec, microcontroller, and radio. The codec including an analog to digital converter for receiving a first audio program and converting it to a first digital signal; a digital to analog converter for receiving a second digital audio signal and converting it to a second audio program; and, a control function for managing characteristics of the codec. The microcontroller is in electrical communication with the codec: for receiving the first digital audio signal from the codec and packetizing it into a first packet for transmission over a TCP/IP network; for receiving a second packet from network and converting it into the second digital audio signal and sending it to the codec; and for receiving control signals from the network. The radio is in electrical communication with the microcontroller for connection to the network to transmit the first packet to the network and receive the second packet from the network.

12 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202310
202214
20201
20193
20183
201721