File size limitations for uncompressed multichannel audio files

[Carsten]

During some recent tests, I ran against the 2/4 GByte filesize limitations of WAV and AIFF file formats. 90min of 24Bit/48KHz at 5.1 will already break the 4GByte barrier. I noticed that Audacity is happy to write these files, but is itself not able to re-open some of these formats properly. Also, DCP-o-matic fails on them. So far it seems, 5.1ch 16Bit 48KHz is the maximum that will fit into 4GB WAV or AIFF for typical longplay feature runtime. 7.1 will already be impossible. Of course, one possible workaround is using individual single channel files. Another is breaking up files in reels, but, coming from contiguous files, that poses the burden of splitting into reels properly (and arranging them in DCP-o-matic) on the user.

I noticed that on a Mac, I can write CAF (Core Audio Format) with Audacity, which is more or less limitless in file size, I also noticed that DCP-o-matic can open CAF files quickly and without problems. I tried to open a W64 (proprietary 64Bit WAV extension) with DCP-o-matic, and that failed. RIFF64 (basically, a large file extension to BWF) also seems to work.

What would be suitable file formats allowing larger file sizes for Linux and Windows, is there one that will work across all platforms?



- Carsten

[gunnar]

You could also export these channels out as 6 separate mono files and then map the audio correctly inside DoM.
If you include in the filename R, C, LFE, Ls and Rs then DoM will most of time automatically map each channel correctly.

[cloud06]

You could also export these channels out as 6 separate mono files and then map the audio correctly inside DoM.
If you include in the filename R, C, LFE, Ls and Rs then DoM will most of time automatically map each channel correctly.

Correct. This is also good thing to do, since that way there is no chance of wrong channel mapping.