#10045 HIGH 1.5-sof: XO-1.5 Record audio/video are out of sync with each other

[Zarro Boogs per Child]

#10045: XO-1.5 Record audio/video are out of sync with each other
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           Reporter:  wad              |       Owner:  dsd                              
               Type:  defect           |      Status:  new                              
           Priority:  high             |   Milestone:  1.5-software-update              
          Component:  record-activity  |     Version:  Development build as of this date
         Resolution:                   |    Keywords:  camera record XO-1.5             
        Next_action:  diagnose         |    Verified:  0                                
Deployment_affected:                   |   Blockedby:                                   
           Blocking:                   |  
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Comment(by Quozl):

 028341a of http://github.com/linux4kix/Record.activity.git tested on
 XO-1.5 C1 with os124.

 The change is to direct video recording output files to /tmp (which is a
 tmpfs) and only write to SD at the end of recording, when the files are
 multiplexed.

 The A/V synchronisation is low (<0.5s) and constant, all the way through
 two minute and six minute recordings.

 Recording to /tmp (47Mb) of the maximum recording time (6 min) costs
 roughly 25Mb when using a complex video stream with many changes in camera
 view.

 Also, a file descriptor leak was detected, with /tmp/output.ogv opened
 once for each video recording start, with the file deleted but the file
 descriptor left open.  The file descriptors are closed when the activity
 is closed.

 Also, with video recording to /tmp active, any filesystem writes to SD via
 SSH caused the same characteristic stutter and synchronisation loss of the
 recording experienced before video recording was swung to /tmp.  This
 suggests that it isn't the writing of the ogv and wav files to SD that is
 the problem, but rather any write to SD.

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Ticket URL: <http://dev.laptop.org/ticket/10045#comment:34>
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