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MCA channel label is missing the channel id property exception

2016-09-08
2016-10-03
  • Grigoriy Gavrilov

    Hi,

    I use mxf2raw utility to get audio samples from mxf wave content. Before MCA inplementig mxf2raw could extraxt audio data but currently the utility exit with exception:

    ERROR: MCA channel label is missing the channel id property
    ERROR:     near MXFFileReader.cpp:1807
    ERROR: BMX exception: MCA channel label is missing the channel id property
    

    Maybe we can disable MCA label check from command line or you know another workaround?

     
  • Philip de Nier

    Philip de Nier - 2016-09-08

    I don't have the SMPTE spec. to hand, but assume that a channel label is required to have that property, hence the check. It's possible I missed a default channel id (=1) is defined for the case of a single channel track, so I'll double check that.

    You'll have to modify and recompile the code to get around that check. You could try commenting out the calls to ProcessMCALabels in bmx/src/mxf_reader/MXFFileReader.cpp, lines 1080 and 1768.

    Philip

     
    • Philip de Nier

      Philip de Nier - 2016-09-09

      I checked and it turns out that the specs. don't mandate the channel id property be present in a channel label. The assumption I make is that a track with a single channel doesn't require the channel label to specifiy a channel id. They don't describe how to interpret a missing channel id if there are multiple channels in the track, and so I'll keep a check in there to disallow that scenario.

      I've pushed a fix to the git repository that will support "missing" channel id properties in tracks containing a single audio channel.

      Philip

       
  • Grigoriy Gavrilov

    Great thank you.