#67 DV codec crashes xvidcap

encoding (15)
Robert Grønning

ver 1.1.5rc1

When using
File Format:DV Video Format (dv)
Video Codec:DV Video

xvidcap --codec dv --format dv --fps 25

It instantly dies when pressing "record" button with the following message:
Segmentation fault (core dumped)

This only happens when using DV format.


    • assigned_to: nobody --> charly4711
    • labels: 573216 --> encoding
    • milestone: --> SVN
    • status: open --> open-accepted
  • Logged In: YES
    Originator: NO

    can reproduce the issue here. One issue is a pointer dereferenced once to many in xtoffmpeg.c. This however, only causes follow-up issues here.

  • Logged In: YES
    Originator: NO

    the initial issue is fixed in svn.
    dv recording still does not work, though. I'm posting this FYI info, because even when this is fixed, dv recording will still only be possible with a very limited set of options. You will then have to do:

    ~/xvidcap/bin/xvidcap --codec dv --format dv --fps 25 --audio_channels 2 --aucodec pcm16 --audio_rate 48000 --audio_bits 64000 --cap_geometry 720x576 --rescale 100 --file out-2.dv

    This is almost the only combination that will work as dv (perhaps only with the ffmpeg encoder, I don't know) has very strict requirements regarding picture format (PAL = 720x576, and don't rescale ... or rescale to get 720x576 as the result), streams 1 video + 1 (or 2) audio stream(s) at 48Khz PCM16.

    At the moment this fails with:
    [dvvideo @ 0x843cf60]Can't process DV frame #0. Insufficient audio data or severe sync problem.

    Apparently this is due to pcm audio capture failing quietly.

  • Logged In: YES
    Originator: NO

    btw. capturing without audio works with svn:
    ~/xvidcap/bin/xvidcap --codec dv --format dv --fps 25 --audio no --cap_geometry 720x576 --rescale 100 --file out-2.dv

  • Logged In: YES
    Originator: NO

    fixed in svn
    that was a nasty one. Researching this showed that audio recording was broken in almost any way. The only thing that was working was what prolly most people are using: sampling directly from /dev/dsp.
    pcm encoding can never have worked before. Now, that should work as all other supported audio codecs with both sampled or piped input.

    • status: open-accepted --> pending-fixed
    • status: pending-fixed --> closed-fixed
  • Logged In: YES
    Originator: NO

    This Tracker item was closed automatically by the system. It was
    previously set to a Pending status, and the original submitter
    did not respond within 14 days (the time period specified by
    the administrator of this Tracker).