AU to WV Converter

AU is an audio file format introduced by Sun Microsystems for its Unix workstations and the NeXT platform. It features a minimal 24-byte header specifying data offset, size, encoding type, sample rate, and channel count, followed by the audio payload. AU supports numerous encodings, including uncompressed linear PCM at various bit depths, mu-law and A-law companding (logarithmic compression used in telephone systems), and several ADPCM variants. This versatility made AU a workhorse across early Unix environments, web audio (Java applets defaulted to AU), and telephony applications. One advantage is simplicity: the compact header and straightforward structure make it trivial to parse, generate, and stream programmatically. The built-in mu-law option provides another benefit, delivering reasonable voice quality at just 8 KB per second — half the rate of 16-bit uncompressed audio — invaluable when storage and bandwidth were scarce. Although modern formats have largely supplanted AU in consumer applications, it retains a foothold in scientific computing and audio processing pipelines where minimal overhead and reliable cross-platform behavior are valued.

WavPack is an open-source audio codec created by David Bryant, with version 1.0 released on August 15, 1998. What sets WavPack apart is its unique hybrid mode: the encoder can simultaneously produce a compact lossy file and a separate correction file that, when combined, reconstruct the original PCM stream bit-for-bit. Users who need portability carry just the lossy file; those who want archival quality keep both. The codec handles PCM audio from 8-bit to 32-bit integer and 32-bit floating point, with sample rates up to 768 kHz — specifications broad enough for DSD content, which WavPack 5 added support for. Compression ratios in pure lossless mode typically reach 40 to 55 percent of the original size, competitive with FLAC and often slightly better on certain material. Multicore encoding in later versions dramatically speeds up processing on modern hardware. The open-source library ships under a BSD license and has been integrated into foobar2000, VLC, FFmpeg, and numerous other tools. WavPack also supports rich metadata through APEv2 tags, embedded cue sheets, and ReplayGain values, covering the organizational needs of even the most meticulous music library.