Au file format
A simple audio file format that consists of a header of 6 32-bit words and then the data. The format was introduced by Sun.
| longword | field | description/ content |
| 0 | magic number | the value 0x2e736e64 (four ASCII characters ".snd") |
| 1 | data offset | the offset to the data in bytes. The minimum valid number is 24 (decimal). |
| 2 | data size | data size in bytes. If unknown, the value 0xffffffff should be used. |
| 3 | encoding | the data encoding format:
value format 1 8-bit ISDN u-law 2 8-bit linear PCM [REF-PCM] 3 16-bit linear PCM 4 24-bit linear PCM 5 32-bit linear PCM 6 32-bit IEEE floating point 7 64-bit IEEE floating point 23 8-bit ISDN u-law compressed using the CCITT G.721 ADPCM voice data encoding scheme. |
| 4 | sample rate | the number of samples/second (e.g., 8000) |
| 5 | channels | the number of interleaved channels (e.g., 1) |