Advanced software implementation of MPEG-4 AAC audio encoder (original) (raw)

New implementation techniques of an efficient MPEG advanced audio coder

IEEE Transactions on Consumer Electronics, 2004

MPEG-AAC is the current state of the art in audio compression technology. The CD-quality promised at bit rate as low as 64 kbps makes AAC a strong candidate for high quality low bandwidth audio streaming applications over wireless network. Besides this low bit rate requirement, the codec must be able to run on personal wireless handheld devices with its inherent low power characteristics. While the AAC standard is definite enough to ensure that a valid AAC stream is correctly decodable by all AAC decoders, it is flexible enough to accommodate variations in implementation, suited to different resources available and application areas. This paper reviews various implementation techniques of the encoder. We then proposed our method of an optimized software implementation of MPEG-AAC (LC profile). The coder is able to perform encoding task using half the processing power compared to standard implementation without significant degradation in quality as shown by both subjective listening test and an ITU-R compliant quality testing program (OPERA).

ISO/IEC MPEG-4 high-definition scalable advanced audio coding

Journal of the Audio …, 2007

Recently the MPEG Audio standardization group has successfully concluded the standardization process on technology for lossless coding of audio signals. A summary of the scalable lossless coding (SLS) technology as one of the results of this standardization work is given. MPEG-4 scalable lossless coding provides a fine-grain scalable lossless extension of the well-known MPEG-4 AAC perceptual audio coder up to fully lossless reconstruction at word lengths and sampling rates typically used for high-resolution audio. The underlying innovative technology is described in detail and its performance is characterized for lossless and near lossless representation, both in conjunction with an AAC coder and as a stand-alone compression engine. A number of application scenarios for the new technology are discussed.

Fast implementation of the MPEG-4 AAC main and low complexity decoder

2004

Abstract We present a fast software implementation of the MPEG-4 AAC (advanced audio coding) main and low complexity (LC) decoder. The reference implementation is analyzed and selected algorithms are presented to improve the performance of most of its building blocks, ie, bitstream de-formatter, noiseless decoding, prediction, and filterbank. The code is further optimized by means of assembler procedures for the filterbank and prediction tools to exploit the Intel Pentium streaming SIMD extension (SSE) instruction set.

Experimental evaluation of encoding parameters of MPEG-4 ALS for high-resolution audio

2017 IEEE 6th Global Conference on Consumer Electronics (GCCE)

This paper describes experimental evaluations of encoding parameters that are appropriate for MPEG-4 Audio Lossless Coding (ALS) to compress high-resolution audio. MPEG-4 ALS Simple Profile defines the values of encoding parameters, such as the maximum sampling frequency and quantization bit depth, for making it easier to implement in the receiving applications. However, ALS Simple Profile does not define values for 96-kHz high-resolution audio. Therefore, we propose a range of values for 96-kHz high-resolution audio by extending the ALS Simple profile and evaluating its performance.

Scalable Perceptual and Lossless Audio Coding based on MPEG-4 AAC

2003

This paper presents a scalable lossless enhancement of MPEG-4 Advanced Audio Coding (AAC). Scalability is achieved in the frequency domain using the Integer Modified Discrete Cosine Transform (IntMDCT), which is an integer approximation of the MDCT providing perfect reconstruction. With this transform, and only minor extension of the bitstream syntax, the MPEG-4 AAC Scalable codec can be extended to a lossless operation. The system provides bit-exact reconstruction of the input signal independent of the implementation accuracy of the AAC core coder. Furthermore, scalability in sampling rate and reconstruction word length is supported.

MPEG-4 ALS-International Standard for Lossless Audio Coding

This article explains the technologies and applications of lossless audio coding. NTT started research on lossless coding of audio signals and proposed the initiation of international standardization in 2002, aiming at high-quality services suitable for broadband networks. As a result of cooperative work with other organizations, the specifications of this technology were officially incorporated in the ISO/IEC MPEG standard published

An Efficient Method to Improve the Audio Quality Using AAC Low Complexity Decoder

Citation/Export MLA D. Kalyanasundaram, K. Santhakumar,, “An Efficient Method to Improve the Audio Quality Using AAC Low Complexity Decoder”, March 15 Volume 3 Issue 3 , International Journal on Recent and Innovation Trends in Computing and Communication (IJRITCC), ISSN: 2321-8169, PP: 1315 - 1319, DOI: 10.17762/ijritcc2321-8169.150391 APA D. Kalyanasundaram, K. Santhakumar,, March 15 Volume 3 Issue 3, “An Efficient Method to Improve the Audio Quality Using AAC Low Complexity Decoder”, International Journal on Recent and Innovation Trends in Computing and Communication (IJRITCC), ISSN: 2321-8169, PP: 1315 - 1319, DOI: 10.17762/ijritcc2321-8169.150391

An Overview of the Coding Standard MPEG-4 Audio Amendments 1 and 2: HE-AAC, SSC, and HE-AAC v2

EURASIP Journal on Audio, Speech, and Music Processing, 2009

In 2003 and 2004, the ISO/IEC MPEG standardization committee added two amendments to their MPEG-4 audio coding standard. These amendments concern parametric coding techniques and encompass Spectral Band Replication (SBR), Sinusoidal Coding (SSC), and Parametric Stereo (PS). In this paper, we will give an overview of the basic ideas behind these techniques and references to more detailed information. Furthermore, the results of listening tests as performed during the final stages of the MPEG-4 standardization process are presented in order to illustrate the performance of these techniques.

An introduction to MPEG-4 audio lossless coding

2004 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2004

Lossless coding will become the latest extension of the MPEG-4 audio standard. In response to a call for proposals, many companies have submitted lossless audio codecs for evaluation. The codec of the Technical University of Berlin was chosen as reference model for MPEG-4 Audio Lossless Coding (ALS), attaining working draft status in July 2003. The encoder is based on linear prediction, which enables high compression even with moderate complexity, while the corresponding decoder is straightforward. The paper describes the basic elements of the codec, points out envisaged applications, and gives an outline of the standardization process.

The MPEG-4 Audio Lossless Coding (ALS) Standard-Technology and Applications

2012

MPEG-4 Audio Lossless Coding (ALS) is a new extension of the MPEG-4 audio coding family. The ALS core codec is based on forward-adaptive linear prediction, which offers remarkable compression together with low complexity. Additional features include long-term prediction, multichannel coding, and compression of floating-point audio material. In this paper authors who have actively contributed to the standard describe the basic elements of the ALS codec with a focus on prediction, entropy coding, and related tools. We also present latest developments in the standardization process and point out the most important applications of this new lossless audio format.