[FFmpeg-user] Input 5.1 DTS, output 2.0 MP3: Atrocious Quality

[John L]

> To: ffmpeg-user at ffmpeg.org
> From: cehoyos at ag.or.at
> Date: Sun, 17 May 2015 07:33:51 +0000
> Subject: Re: [FFmpeg-user] Input 5.1 DTS, output 2.0 MP3: Atrocious Quality
> 
> John L <orionfyre <at> hotmail.com> writes:
> 
> > But I'm still curious why it would behave in such a way
> 
> Me too!
> So please test the following and report back:
> ffmpeg -i inter.dts -acodec pcm_f32le -ac 2 out.wav
> 
> Carl Eugen

I had run the command as requested in my last email to this thread. I'll repost the pertinent part here

I ran the following command line and received the following:
--------------------------------
ffmpeg -loglevel debug -i inter.dts -c:a pcm_f32le -ac 2 -y inter-f32le.wav
....
[AVFilterGraph @ 0xca9d20] query_formats: 4 queried, 6 merged, 3 already done, 0 delayed
1.000000 0.000000 0.707107 0.000000 0.707107 0.000000 
0.000000 1.000000 0.707107 0.000000 0.000000 0.707107 
[auto-inserted resampler 0 @ 0xc965c0] ch:6 chl:5.1(side) fmt:fltp r:48000Hz -> ch:2 chl:stereo fmt:flt r:48000Hz
-----------------------------
the resulting wav file is significantly distorted, but qualitatively doesn't 'feel' as harsh
 
And as you expected, both s16le nor s32le result in acceptable files for both:
ffmpeg -loglevel debug -i inter.dts -c:a pcm_s16le -ac 2 -y inter-s16le.wav
ffmpeg -loglevel debug -i inter.dts -c:a pcm_s32le -ac 2 -y inter-s32le.wav