FFMPEG and ac3 files @640kbps

[fbd]

Hi,

I use ffmpeg to transcode my .ac3(5.1) files to .aac(5.1).
This is my command line :
ffmpeg.exe -i "%~f1" -acodec mpeg4aac -ab 448k -ac 6 "%~dpn1.aac"

For ac3 files >= @640kbps , ffmpeg says: "Could not find codec parameters"...

Do you know this error?

Thanks

[Kurtnoise]

For ac3 files >= @640kbps , ffmpeg says: "Could not find codec parameters"...

Do you know this error?

Obviously, the ac3 decoder from your FFmpeg build doesn't support yet the ac3 streams from BD and HD-DVD.

[jruggle]

For ac3 files >= @640kbps , ffmpeg says: "Could not find codec parameters"...

There are a few things which could cause that error. First of all, Kurtnoise is correct about FFmpeg not supporting ac3 over 640kbps, which is really enhanced ac3. But if it really is just plain ac3, you can still get that error sometimes. Try using something like:
ffmpeg -f ac3 -i your_input_file.ac3 -acodec aac -ab 448k -ac 6 your_output_file.aac

A possible reason is that the raw ac3 detection code is fairly weak right now, especially for high bitrate files (I'm working on a fix). You sometimes have to force the raw ac3 format in order for it to be recognized as such.

[fbd]

There are a few things which could cause that error. First of all, Kurtnoise is correct about FFmpeg not supporting ac3 over 640kbps, which is really enhanced ac3. But if it really is just plain ac3, you can still get that error sometimes. Try using something like:
ffmpeg -f ac3 -i your_input_file.ac3 -acodec aac -ab 448k -ac 6 your_output_file.aac

A possible reason is that the raw ac3 detection code is fairly weak right now, especially for high bitrate files (I'm working on a fix). You sometimes have to force the raw ac3 format in order for it to be recognized as such.


:thanks::thanks: it's WORKKKKKS Thanks jruggle :)