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.

Optimizing frequent in-band signaling in dual sim dual active devices

Abstract: A method includes: receiving a first speech frame; identifying a first codec mode based at least in part on a Codec Mode Command (CMC) comprising the first speech frame; identifying a second codec mode based at least in part on a downlink (DL) Codec Mode Indication (DCMI) comprising the first speech frame; determining, based at least in part on a current uplink (UL) codec mode, to apply one of the first codec mode, the second codec mode, and a third codec mode having a higher bit rate than the first codec mode; and applying one of the first codec mode, the second codec mode, and the third codec mode.

An efficient fixed codebook search for G.729 speech codec derived from RCM-based search algorithm

Abstract: This work aims to present a combined version of reduced candidate mechanism (RCM) and iteration-free pulse replacement (IFPR) as a novel and efficient way to enhance the performance of algebraic codebook search in an algebraic code-excited linear-prediction (ACELP) speech coder. As the first step, individual pulse contribution in each track is given by RCM, and the value of N is then specified. Subsequently, the replacement of a pulse is performed through the search over the sorted top N pulses by IFPR, and those of 2 to 4 pulses are carried out by a standard IFPR. Implemented on a G.729A speech codec, this proposal requires as few as 24 searches, a search load tantamount to 7.5% of G.729A, 37.5% of the global pulse replacement method (iteration=2), 50% of IFPR, but still provides a comparable speech quality in any case. The aim of significant search performance improvement is achieved in this work.

A lossless audio codec based on hierarchical residual prediction

Abstract: In this study, we propose a novel lossless audio codec that exhibits precise prediction performance leveraging a neural network with fast decoding speed. The proposed network structure is identical to the ResNet; we repeatedly predict on residual. Furthermore, we propose optimal parameter setting tactics for the recursive Golomb-Rice coding. Finally, we implement the codec and experimentally compare its performance with that of state-of-the-art codecs. We confirmed practical decoding speed and higher compression ability than other methods, except for Monkey's Audio.

A wideband differential coding algorithm

Abstract: We examine an old waveform coding technique, D*PCM, in the context of wideband coding of speech and audio. We show that the use of a modified form of this approach has the promise of providing a very low complexity, high quality, wideband audio coder.

Encoder and decoder driver development techniques

Abstract: A codec architecture including an audio wave driver and a coded topology driver. The audio wave driver is communicatively coupled to an audio engine and an analog audio codec. The coded topology driver is communicatively coupled to the audio wave driver by a set of interfaces that enables streamlined code implementation, improved operation efficiency and power savings, while allowing vendors to supply differentiating functionality outside of the basic requirements of the operating system.