Format pliku

O plikach AU

AU (Sun AU Audio · Format audio)

Rok wydania 1988 Twórca: Sun Microsystems

Sun AU Audio (.au) to standardowy format plików obsługiwany przez KaijuConverter do wymiany danych, archiwizacji i szybkiej konwersji wieloplatformowej.

Kategoria

Audio Files

Rozszerzenie

.au

Typ MIME

audio/basic

Dostępny jako

Wejście Wyjście

Historia powstania

JAK FORMAT AU
POWSTAŁ.

AU — sometimes called Sun au or NeXT/Sun audio — was the native uncompressed audio format on Sun SPARC workstations and NeXT computers in the late 1980s. The header is 24 bytes, minimalist: magic number, data offset, size, encoding code, sample rate, channels, and an optional text annotation. After that comes raw audio samples, usually 8-bit µ-law or 16-bit PCM.

AU achieved minor immortality in the Java world because the early Applet API used it as the default audio format for java.applet.Applet.play(). Every "Web 1.0" applet that played a sound played a .au file. Outside Java and Sun workstation archives, AU is effectively extinct — supplanted by WAV on Windows, AIFF on Mac, and OGG/MP3 on the web. FFmpeg and sox still read and write it for compatibility.

CIEKAWOSTKI I
FAKTY.

Java applets used .au as their default audio format via Applet.play() — every Web 1.0 applet chime came from a .au file.

The AU header is just 24 bytes — one of the simplest audio file formats ever designed.

Sun workstations shipped with cowbell.au, crash.au, ding.au, and rooster.au as standard system sounds — now internet nostalgia artifacts.

NeXT computers (including Steve Jobs' post-Apple workstation) used AU as the native audio format.

The format supports µ-law compression — the same logarithmic PCM encoding used in North American telephony.

ZALETY I
OGRANICZENIA.

Zalety

Trivially simple format — 24-byte header, then samples.
µ-law 8-bit variant fits hours of speech in kilobytes.
Stable since 1988; every major audio library reads it.
Streaming-friendly: size field is optional.

Ograniczenia

Aging — obsolete outside legacy and compatibility scenarios.
No metadata beyond a single annotation string.
No native multi-channel surround support.
Limited to 8 codecs, none modern.

Typowe rozmiary i waga plików

10-second clip (8-bit µ-law, 8 kHz)

80 KB

10-second clip (16-bit PCM, 44.1 kHz stereo)

~1.7 MB

Specyfikacja techniczna

MIME types: audio/basic, audio/au, audio/x-au
Extensions: .au, .snd
Header: 24 bytes (magic, offset, size, encoding, rate, channels, info)
Codecs: PCM 8/16/24/32-bit, µ-law, A-law, IEEE float
Byte order: Big-endian

KONWERTUJ Z
AU

au mp3 au wav au flac au aac au m4a au ogg au opus au wma au aiff

KONWERTUJ NA
AU

mp3 au wav au flac au aac au ogg au opus au m4a au

Typowe zastosowania

Unix audio, telephony