mlv_sound working only on the first video

Issue #2255 resolved
Licaon Kter created an issue

I was testing out RAW recording on my M1, having mlv_sound loaded besides mlv_rec I got sound only on the first recorded video.

Build info:

Magic Lantern version : Nightly.2015Apr07.EOSM202
Mercurial changeset   : de7779da4ac8 (unified) tip
Built on 2015-04-06 22:09:09 UTC by

Steps to reproduce:

  • Start ML sound bars move
  • Start MLV RAW recording
  • Sound bars move
  • Stop MLV RAW recording
  • Sound was recorded OK
  • Sound bars don't move any more
  • Open Canon Menu via MENU button ( don't change anything )
  • Close Canon Menu via MENU button
  • Sound bars start to move again
  • Start MLV RAW recording
  • Sound bars move
  • Stop MLV RAW recording
  • BUT sound was not recorded
  • Sound bars don't move anymore

After the first video, retrying to record yields a red message according to /modules/mlv_snd/mlv_snd.c:231: "audio failed to stop, state 4" when pressing record at the end of the video, retrying multiple times, say 3 or 4 will finally yields a message according to /modules/mlv_rec/mlv_rec.c:3226: "Threads failed to start". After this appears pressing record button doesn't do anything any more ( but 600 bytes MLV and nine 52 bytes M00..M08 files are created every time) also invoking the Canon MENU can stop the camera.

See this video:!cchR2TiJ!lG7s5q2cw4P2oQkd0GrZFuEtiMsXBEOLSEEbtgeBW58

Not sure if this should be split in 2 issues:

  1. sound bars stopping after the first recording but moving again by triggering the Canon MENU on and off
  2. sound recording stopping after the first video recording and never recovering until a camera restart

/PS: forum thread:

Comments (12)

  1. Daniel Fort

    Followed your instructions and reproduced the issues you reported.

    I created a couple of 1 minute MLV clips and only the first video had audio. After recording the first clip the audio bars stopped moving but can be reactivated by turning the Canon MENU on and off. The recording on the second clip ended with the "audio failed to stop, state 4" message and no audio in the clip. Attempting further recording gave the "Threads failed to start" and created nine 53 byte files. Also confirmed that invoking the Canon MENU or INFO stops the camera.

    In order to successfully record MLV clips with audio it is necessary to cycle power after each recording.

  2. Daniel Fort

    Oops--thought I did something wrong when it didn't show up on the pull requests list. Made a new pull request against the unified branch. I'm still very new at this stuff.

  3. Daniel Fort

    Forgot to comment out old SoundDevShutDownIn so I need to make another pull request. @nikfreak pointed that out on the pull request after it was merged. The weird thing is that now that I have a ROM1.BIN disassembly, the previous SoundDevShutDownIn seems to have the "proper" address. The only other place SoundDevShutDownIn is used is in beep.c -- wondering if I broke anything there, I never played around with the camera beeps.

  4. Daniel Fort

    Well then it doesn't matter.

    Funny thing is that since the new SoundDevShutDownIn comes later in stubs.S it overwrites the previous SoundDevShutDownIn. Fixing it would just be for good form. Maybe it would be a good time to add back some of the other stubs that were lost in the Tragic Lantern merge and tidy things up with the contrib/stub-format tools?

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