I don't know why MediaInfo shows something like that as "Sample Count", but I think it's not problem of qaac.You can dump mp4 file structure by tools like mp4box or boxdumper (of L-SMASH), which is FAR more reliable than MediaInfo when you want to inspect MP4.
More graphical with MeGUI:[...]
Quote from: LigH on 28 January, 2013, 10:40:20 AMMore graphical with MeGUI:[...]Thanks, but this create a corrupt audio file (MediaInfo Bitrate 2kbit/s) and i think the reason could be, that I have some 2.0 parts in the 5.1 audio source.Can I "force" 5.1 in megui like -ac 6 in ffmpeg? Or can I convert the ac3-source lossles to a compleate 5.1 ac3-file?
eac3to input.ac3 stdout.wav | qaac - -o "output.mp4" -i --verbose --threading
and i think the reason could be, that I have some 2.0 parts in the 5.1 audio source.
You can also have QAAC output *.m4a by omitting "--adts"; I would prefer it in an MP4 container if it will be multiplexed later.
@sneakerYou might want to specify -acodec pcm_f32le to avoid unnecessary quantization to pcm_s16le by ffmpeg. qaac can read float WAV just fine.
Thanks for the tip, though it does not seem to make a difference for ffmpeg's ac3 decoder. Usually I use eac3to as suggested by LastSilmaril because the author does keep proper bit depth conversions in mind, though it "only" uses 24 bit by default for the output.
Quote from: sneaker on 28 January, 2013, 11:52:56 PMThanks for the tip, though it does not seem to make a difference for ffmpeg's ac3 decoder. Usually I use eac3to as suggested by LastSilmaril because the author does keep proper bit depth conversions in mind, though it "only" uses 24 bit by default for the output.Hmm, I tried with ffmpeg just now, and seems you are correct. Actually I was using avconv instead of ffmpeg, and it gives you different result.
Tried this with latest ffmpeg binary from http://ffmpeg.zeranoe.com/builds/, and now ffmpeg can correctly output without integer clipping with -acodec pcm_f32le. The version I tried seems just too old (it was built on Nov 2012 or so, therefore it was not VERY old, but ffmpeg is really a moving target).
ffmpeg also supports pcm_f64le. Would it make any sense to use it with qaac?
Quote from: sneaker on 08 February, 2013, 08:14:24 AMffmpeg also supports pcm_f64le. Would it make any sense to use it with qaac?qaac can read f64, but I don't think it will make any sense.
But it won't break anything even if there's zero practical advantage?
Will I get proper channel order for my 5.1-channel AAC file if I first decode the DTS-HD MA track to a multichannel wav file with eac3to and then encode that one with qaac? I need to decode to wav as there's sometimes clipping in the decoded output and eac3to needs a second pass to handle it.
Sorry, should have been a bit more clear. Clipping is sometimes detected when downmixing 7.1ch or 6.1ch to 5.1ch.