[Traverso-devel] Large file support

[Remon]

Hi,

The wave file format is limited to 2 GB files iirc, which can be reached 
quickly, specially since we record to interleaved files now in case of 
recording to more then one channel.

The only format I could find that uses 64 bit offsets instead of 32 bit 
supported by libsndfile is Sonic Foundry's 64 bit RIFF/WAV, and has 
extension .w64

To see how and if that worked, I recorded about 8 hours into w64 with 
Traverso, and it works just fine, the file is ~ 10 GB large :)

So far everything seems fine, however, popular players which use e.g. xine as 
engine do not recognize the format, so in case someone wants to reuse a 
recording directly from the audiosources directory of a traverso project, 
playback becomes a little problematic, though all players that use libsndfile 
are/should be able to playback it just fine!

My suggestion is to make using w64 or wav optional, but default to w64, to 
avoid potential long recordings to fail.
RFC please.

Although it's unlikely that files will be larger then 4 GB, opening larger 
files with fopen() won't work unless traverso is compiled with large file 
support.
I've updated cvs, for linux the proper compile flags are added to be able to 
open files that are larger then 4 GB

This makes sense for detecting the file type, e.g. VorbisReader (which failed 
to fopen() the recorded 10 GB w64 file) and in case of WavPackWriter (WavPack 
currently doesn't support large files, but it's planned for future versions)

I don't suspect ogg files > 4 GB, neither for WavPack but in the case of 
WavPack it could make sense if someone wants to record to a stereo file for > 
~ 5 hours (of course, when a WavPack version will be released that supports 
large files).

Anyways, the compile flags seem to be different for mac os x, so if somebody 
wants to give it a shot....

A site I found about large file support might be of interest [1]

Summarizing, compilation with large file support isn't a big issue for now, 
since libsndfile handles the w64 files just fine, and WavPack itself doesn't 
support large files yet currently.

Using the w64 as default recording format would be favorable but I'd like to 
hear your opinion as well!


Regards,

Remon

[1] http://www.suse.de/~aj/linux_lfs.html