Audio Drop Outs in Vegas

rtbond wrote on 2/23/2009, 11:32 AM
Folks,

I have encountered audio drop outs on the Vegas timeline (v 8.1 and v8.0) on several (not all) captured HDV tapes. If I play the captured media (mt2 file) outside of Vegas the audio is fine (i.e., no drop-out).

When a drop occurs it appears to be at a point on the tape where the camera was powered-off and then back on. Also, when I play the captured media outside of Vegas it appears there is some anomaly at the camera off/on transition point as the playback (e.g., in VLC player) video freezes momentarily at that point, but then recovers after a couple of seconds. I am guessing whatever is in the captured file at this point is causing Vegas to stop processing the audio from that point forward in the file (although at some point after the audio drop-out in Vegas the audio does return).

Any thoughts? (what is likely the cause, how to avoid it in the future, possible corrective capture actions?). It appears Vegas is not handling "hiccup" (bad time code data?) in the captured video very well, resulting in dropping the audio for period of time after the occurrence.

The media was captured with HDVSplit, as I have avoided the Vegas capture utility because of the in ability to suppress the scene detection feature (i.e., when I configure the HDV capture to not use scene detection it still produces multiple files during the capture process.)

My workaround has been to capture the tape in sections around the point in time that is causing problem in Vegas (which means I loose a little bit of recorded material)

Thanks!

Rob Bond

My System Info:

  • Vegas Pro 22 Build 194
  • OS: Windows 11.0 Home (64-bit), Version: 10.0.26100 Build 26100
  • Processor: i9-10940X CPU @ 3.30GHz (14 core)
  • Physical memory: 64GB (Corsair Vengeance LPX 64GB (2 x 32GB) DDR4 DRAM 3200MHz C16 memory kit)
  • Motherboard Model: MSI x299 Creator (MS-7B96)
  • GPU: EVGA GeForce RTX 2070 SUPER XC ULTRA (Studio Driver Version =  536.40)
  • Storage: Dual Samsung 970 EVO 1TB SSD (boot and Render); WDC WD4004FZWX, 7200 RPM (media)
  • Primary Display: Dell UltraSharp 27, U2723QE, 4K monitor with 98% DCI-P3 and DisplayHDR 400 with Dell Display Manager
  • Secondary Display: LG 32UK550-B, entry-level 4k/HDR-10 level monitor, @95% DCI-P3 coverage

Comments

farss wrote on 2/23/2009, 12:28 PM
Best solution is to shoot with this problem in mind. Even playing back hdv tapes directly I see some of this. Think of shooting HDV as you would shooting 35mm or maybe 65mm, the camera needs time to come up to 'speed'. Also allow a few seconds for the camera to wind down.

I don't know for certain why all this happens. It must have something to do with how HDV is recorded in long GOPs. The audio does not seem to be recorded as one frame of sound with one frame of vision.

Bob.