Lossless coding is the latest extension of the MPEG-4 audio standard. The MPEG audio subgroup has finalized the standardization of lossless coding techniques for high-definition audio signals. As an extension to MPEG-4 audio, the "MPEG-4 Audio Lossless Coding (ALS)" standard defines methods for lossless coding.
Features of MPEG-4 ALS
MPEG-4 ALS defines efficient and fast lossless audio compression techniques for both professional and consumer applications. It offers many features not included in other lossless compression schemes.
- General support for virtually any uncompressed digital audio format (including wav, aiff, au, bwf, raw).
- Support for PCM resolutions of up to 32-bit at arbitrary sampling rate (including 16/44.1, 16/48, 24/48, 24/96, 24/192).
- Multi-channel / multi-track support for up to 65536 channels (including 5.1 surround).
- Support for 32-bit IEEE floating point audio data.
- Fast random access to any part of the encoded data.
- Optional storage in MP4 file format (allows multiplex with video).
- High flexibility of codec parameters for various applications.
Besides these outstanding features, a global MPEG standard for lossless audio coding will facilitate interoperability between different hardware and software platforms, and will thus promote long-lasting multivendor support.
How to install it?
Simply unzip the archive and copy the file "in_mp4als.dll" into the "Winamp\Plugins" directory.
In order to enable fast seek operations, files should be encoded using random access points (encoder option -r#, e.g. -r5 for 500ms, preferably together with -u1).