[FFmpeg-devel] Swresample strangeness

[Marton Balint]

Hi,

I am working on a patch to select a better default packet size for the wav 
demuxer, since it reads at most 4096 bytes which can cause insanely small 
packets for files with high channel count.

Unfortunately some swresample fate tests blew up, and I wonder if the 
result of the resampling should be dependant on size of the audio chunks 
which are being fed to it. My assumption is that if it causes 
audible difference in the output, then it is likely a bug in swresample, 
but I am not familiar with its code and its many tunable variables, so if 
someone could confirm, (or even better, fix it :)) that would be great.

Here is a simple command line which should produce silence, but there is 
an audible regular clicking instead:

ffplay -f lavfi -i \
"sine=440:r=8000:samples_per_frame=2048,aresample=44100:filter_size=1:phase_shift=0,aresample=8000,aformat=cl=mono[a];
  sine=440:r=8000:samples_per_frame=320, aresample=44100:filter_size=1:phase_shift=0,aresample=8000,aformat=cl=mono[b];
  [a][b]amerge,pan=mono|c0=c1-c0"

Thanks,
Marton