the audio duration changes about opus-tools HOT 4 CLOSED

If you use opusenc to encode a wav file and then opusdec to decode, the duration of the resulting wav file should be the same (for up to 48 kHz sample rate). What sample rate and duration are your original and decoded wav files?

opus_demo only produces complete packets, which are 20 ms by default, so using opus_demo it is expected that the duration will be off by up to 1 packet.

from opus-tools.

I noticed the same issue after trying opusenc today (see xiph/opus#249), and while there indeed is a small (added) duration difference with PCM inputs, its even worse with flac inputs.

I investigated the flac issue, and it seems to be caused by the latest commit 5d0ac20

More specifically, it looks like during input file identification, too much data is being consumed, causing some data at the start to be lost. If I revert this change, the output duration is now again the same as with a PCM input (so still not exactly like the original)

from opus-tools.

while there indeed is a small (added) duration difference with PCM inputs

Actually, after looking at the output with opusinfo, I'm not so sure anymore about this. It reports a playback length of 44.119s, while audacity reports a length of 44.134s (I think audacity uses ffmpeg to decode the file).

The playback length of original PCM input is reported as 44.120s in audacity, so I guess its close enough to the reported output of opusinfo?

from opus-tools.

The difference with opus_demo is explained above, and the issue affecting FLAC input files has been fixed in ecd50e5.

from opus-tools.