wav file export 6hours 45min maximum?

Audacity 3 Help Forum Windows
1

For years I have created podcast loops of 6-hour lengths which I export in single wav files.
File size is a hefty 3.7 GB but this has always worked.

Now the required length increased to 8 hours and the file size is unsurprisingly 4.9 GB…

BUT!

The indicated audio length in Windows is only 1 hour 14 minutes!
And in both the windows media player and VLC player, it really does stop there.

I have now been experimenting with different lengths. The trouble starts at the 4 GB file size boundary.
6h45min (4.18 GB) displays the correct length and plays all the way through.
6h58min (4.3 GB) only displays 12min and stops at 12min.

I have tried exporting entire files and also selected portions.
I have also tried a completely fresh project (8hours!!!) and still get the same result.

It looks very much like Audacity is using a 32bit length value for the WAV length header parameter.

I used 2.0.2 for a long time on Win 8.1
When I hit this problem last night I installed 2.1.1 with the new ffmpeg library (manually with zip, not exe installer)

The problem is reproducible in both versions.

2

Yes it is - as per the WAV format specification: WAV - Wikipedia

3

Now the required length increased to 8 hours and the file size is unsurprisingly 4.9 GB…

What are your format requirements? As far as I know, only WAV & AIFF are size-limited. Try FLAC, RF64, or W64. Or, MP3 or MP4/AAC if lossy compression is OK.

It looks very much like Audacity is using a 32bit length value for the WAV length header parameter.

The surprising thing is that the original file-size limit was 2GB, which means the size-chunk field was being treated as a signed integer. That doesn’t make any sense but I believe there are some applications that will choke with WAVs bigger than 2GB.

4

Ah, of course. Thanks for the link!
And to think I worked on tools for AKAI wav files… that was long ago (it shows).