Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've got a number of audio recordings which I can't play back. It appears to be a case of a missing codec, but I can't locate the codec in question.

VLC will not play the files. ffmpeg gives the error Unsupported codec (id=0) for input stream 0.

This is the output from MediaInfo.

General
CompleteName                     : 

Format                           : Wave
FileSize/String                  : 164 KiB
Duration/String                  : 1mn 24s
OverallBitRate/String            : 16.0 Kbps

Audio
Format                           : ADPCM
CodecID                          : 64
CodecID/Info                     : G.726
CodecID/Hint                     : APICOM
Duration/String                  : 1mn 24s
BitRate_Mode/String              : Constant
BitRate/String                   : 16.0 Kbps
Channel(s)/String                : 1 channel
SamplingRate/String              : 8 000 Hz
BitDepth/String                  : 2 bits
StreamSize/String                : 164 KiB (100%)

Can anyone help?

share|improve this question
up vote 2 down vote accepted

http://stackoverflow.com/questions/2508717/how-do-i-convert-a-g-726-adpcm-signal-into-a-pcm-signal

share|improve this answer
    
this is very interesting, thank you. I've been playing with the settings of decode-g72x and it does produce an audible wav, but so far the audio is garbled. I shall keep playing... – Colin Pickard May 28 '10 at 11:20
    
It turned out that this method would actually work, if the source files were not corrupted... Thank you – Colin Pickard Sep 17 '10 at 13:32

This is a long shot, but I got some results before by Importing the file into Audacity, via the Project menu -> "Import Raw Data". ADPCM is there in the list, just match up the sampling rate and any other fields, and try different byte-orders if you get bad results.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .