Marc Lavall?e wrote: ... > I don't know if the fine Xiph developers can "just" extend the > definitions of FLAC, if a special Ambisonics mode would be required, and > to what extent the 8-channel limit (as a limit) is a political issue.
Extending a FLAC stream beyond eight channels is not possible. There are two problems; one simple, one less so: The simple problem is that the field in the header used for the number of channels is only three bits. Perhaps comparing FLAC with the Ogg container and Vorbis codec will aid understanding of the more difficult problem. With Ogg, different streams can be either chained (sequential) or grouped (parallel/interleaved). Typically, metadata streams would be chained (so they appear before any audio data) and audio streams would be grouped. Within a single FLAC stream the audio is split into blocks which are grouped. But within each block the eight channels are chained. This makes sense with a maximum of only eight channels. Within a Vorbis stream the audio is split into frames which are grouped. However, because a Vorbis stream can contain up to 256 channels, within each frame the channels are also grouped. So the maximum of eight channels is really embedded into the FLAC standard. To change this would require a whole new standard (or the use of multiple grouped FLAC streams in an Ogg container). Regards, Martin -- Martin J Leese E-mail: martin.leese stanfordalumni.org Web: http://members.tripod.com/martin_leese/ _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
