FLAC stands for Free Lossless Audio Codec, an audio format similar to MP3, but lossless, meaning that audio is compressed in FLAC without any loss in quality. This is similar to how Zip works, except with FLAC you will get much better compression because it is designed specifically for audio, and you can play back compressed FLAC files in your favorite player (or your car or home stereo, see supported devices) just like you would an MP3 file.
FLAC stands out as the fastest and most widely supported lossless audio codec, and the only one that at once is non-proprietary, is unencumbered by patents, has an open-source reference implementation, has a well documented format and API, and has several other independent implementations.
1.3.201 Jan 2017 17:58
Fix undefined behaviour using GCC/Clang UBSAN (erikd).
General hardening via fuzz testing with AFL (erikd and others).
General code improvements (lvqcl, erikd and others).
Add FLAC in MP4 specification docs (Ralph Giles).
MSVS build cleanups (lvqcl).
Fix some cppcheck warnings (erikd).
Assume all currently used OSes support SSE2.
Fix potential infinite loop on flac-to-flac conversion (erikd).
Add WAVEFORMATEXTENSIBLE to WAV (as needed) when decoding (lvqcl).
Only write vorbis-comments if they are non-empty.
Error out if decoding RAW with bits != (8 16 24).
Add --scan-replay-gain option.
-- build system:
Fixes for MSVC and Makefile.lite build systems.
CPU detection cleanup and fixes (Julian Calaby, erikd and lvqcl).
Fix two stream decoder bugs (Max Kellermann).
Fix a NULL dereference bug (on a malformed file).
Changed the LPC order guess for a slight compression improvement, particularly for classical music (Martijn van Beurden).
Improved encoding speed on older Intel CPUs.
Fixed a seeking bug when decoding certain files (Miroslav Lichvar).
Put an upper bound (32768) on the number of seek points.
Fix potential memory leaks.
Support 64bit brword/bwword allowing FLAC__BYTES_PER_WORD to be set to 8 (disabled by default).
Fix an out-of-bounds heap read.
Win32: Only use large buffers when writing to disk.