Nine years after the release of the last major version, the Xiph.Org community has introduced a new version of the free FLAC codec, 1.4.0, which provides lossless audio coding. FLAC employs only lossless encoding methods, ensuring complete preservation of the original quality of the audio stream and its identity with the reference version that underwent encoding. The lossless compression methods used reduce the size of the original audio stream by 50-60%. FLAC is a completely free streaming format, implying not only the openness of libraries implementing encoding and decoding functions but also no restrictions on using the specifications and creating derivative versions. The library code is distributed under the BSD license.
Among the most important changes are:
- Support for encoding and decoding with a 32-bit quantization bit depth per sample.
- Compression efficiency has been improved at levels 3 to 8, at the cost of a slight decrease in encoding speed due to increased accuracy of autocorrelation calculation. Encoding speed has increased for levels 0, 1, and 2. Compression has been slightly improved at levels 1 to 4 due to changes in adaptive heuristics.
- Compression speed has significantly increased on 64-bit ARMv8 processors, thanks to the use of NEON instructions. Performance has been enhanced on x86_64 processors that support the FMA instruction set.
- The API and ABI of the libFLAC and libFLAC++ libraries have been changed (applications need to be rebuilt when updating to version 1.4).
- The XMMS plugin has been deprecated and will be removed in the next release.
- The libFLAC library and the flac utility now allow setting a minimum bitrate limit for FLAC files, down to 1 bit per sample (which may be useful for live broadcasting).
- It is now possible to encode files with a sampling rate of up to 1048575 Hz.
- New options ‘—limit-min-bitrate’ and ‘—keep-foreign-metadata-if-present’ have been implemented in the flac utility.
Source: opennet.ru
