[flac-dev] Question from Argentina

Federico Miyara fmiyara at fceia.unr.edu.ar
Wed Jun 12 18:25:43 PDT 2013


Dear Erik,

>Its not that we need space for 7616 years, its that if we only use
>32 bit offsets, then we would be limited to files of 2 Gigabytes
>(signed 32 bit integer) is simply not enough.
>
>For instance, at 96kHz/24 bits, recording 8 channels would chew up
>the 2Gigabytes in about 15 minutes. Some songs are longer than that,
>
>If 32 bits is not enough, the next logical amount is 64 bits.

Fact is that FLAC is highly economical in items such as reserving 20 
bits for sampling rate or 3 bits in the middle of the middle of a 
byte for number of channels (which are, in fact, currently too few 
for applications such as beamforming that use arrays of several dozen 
microphones), so the next logical amount could easily be 40 bits, 
which would suffice for 50 h recording at 192 kHz / 32 bits / 8 
channels; or even 48 bit, which allows for 1.5 year recordings (not 
unlikely, however, in long-term soundscape continuous recordings).

If the file turns to be that huge, an efficient search would demand 
probably quite a few seek points, perhaps about 0.01 % the sample 
count, which might involve a huge amount of extra bytes because of 
this choice (4 bytes per seek point, assuming 64 bit instead of 48 above).

I don't find this explanation convincing enough. May be there is 
another reason that just reserving space for the far far future?

Best regards,

Federico  



More information about the flac-dev mailing list