WavPack is a free, open source lossless audio compression format developed by David Bryant.
WavPack allows users to compress (and restore) both 16 and 24-bit audio files in the .WAV format. It also supports multichannel streams and high frequency sampling rates. Like other lossless compression schemes the data reduction varies with the source, but it is generally between 25% and 50% for typical popular music and somewhat better than that for classical music and other sources with greater dynamic range.
WavPack also incorporates a unique "hybrid" mode that provides all the advantages of lossless compression with an additional bonus. Instead of creating a single file, this mode creates both a relatively small, high-quality lossy file that can be used all by itself, and a "correction" file that (when combined with the lossy file) provides full lossless restoration. For some users this means never having to choose between lossless and lossy compression!
- Fast and efficient encoding and decoding
- Open source, released under a BSDish license
- Error robustness
- Streaming support
- Supports multichannel audio and high resolutions
- Hybrid/lossy mode
- Tagging support (ID3v1, APE)
- Supports RIFF chunks
- Supports embedded CUE sheets
- Includes MD5 hashes for quick integrity checking
- ReplayGain compatible
David Bryant started development on WavPack in mid-1998, with the release of version 1.0. This first version compressed and decompressed audio losslessly, nothing else, but by then it already featured one of the best efficiency vs. speed ratio among lossless encoders.
Very soon after the release of version 1.0, Bryant released v. 2.0, which featured lossy encoding (using only quantization for data reduction - no psychoacoustic process was applied to the stream).
In 1999, the developer released version 3.0, which featured novelties such as a fast mode (with reduced compression ratio), compression of RAW files and error detection using CRC checksums.
WavPack development is still going on, and a major feature added in late 3.x versions is the hybrid mode, where the encoder generates a lossy file + a correction file, so that both can be decompressed back to the original PCM stream.
WavPack 4 has been recently released. It included important changes, such as fast seeking, multichannel support, high resolution audio support, etc. turning it into one of the most full featured and modern lossless audio compressors.