WRID>RIFF-WAVE>fact
TODO: overview
The "fact" chunk is required if the waveform data is contained in a "wavl" LIST chunk and for all compressed audio formats. The chunk is not required for PCM files using the "data" chunk format.
[RIFF1991]
...
| Chunk | Name | Bytes | Type | condition | Description | WRID |
|---|---|---|---|---|---|---|
| fact | id |
4 |
u8[4] |
id = fact
|
...>id | |
| fact | size |
4 |
u32 |
|
...>size | |
| fact | samples |
4 |
u32 |
|
Number of samples. RIFF1991 named this field dwFileSize, even though it's documented as "Number of samples" | ...>samples |
...
The "fact" chunk will be expanded to include any other information required by future WAVE formats. Added fields will appear following the
[RIFF1991]field. Applications can use the chunk size field to determine which fields are present.
The above seems... not great. :/ It looks as though the various compressed file formats optionally add additional data here. TODO: find and add refrence supporting this comment.
TODO: check and see if [RIFF1994] adds more.
Learning References
Specification
- [RIFF1991] Multimedia Programming Interface and Data Specifications 1.0(1991). See pages 56-65.
- [RIFF1994] New Multimedia Data Types and Data Techniques 3.0(1994). See pages 12-22.