• Compression Techniques

  Inconsistent bad ProRes outputs (video and audio out of sync)

  Posted by Evan Griffin on July 16, 2013 at 9:14 pm

  Running batch conversions of H.264 5D/7D footage to ProRes 422 LT results in a large number of files with out of sync audio and video. I opened the out of sync clips in Quicktime Pro, looked at the properties and saw that the video and audio tracks had different durations. One example is video duration: 46.96. Audio duration: 46.79. All of the out of sync clips have this problem with the video/audio duration and it’s always video that’s longer than audio. The source H.264 files have the same duration for audio and video tracks.

  I tried running my transcodes in Squeeze 9 Pro, Squeeze 8.5 Pro, and MPEG Streamclip. Streamclip produced more correct files than Squeeze, but there were still some that were wrong. I’m going to be ProResing hundreds of clips and I can’t check them individually.

  I also tried running the transcodes on another computer with Squeeze 8.5 Pro and Streamclip and the outputs were fine. I think the problem is related to my computer somehow (corrupt or incomplete codecs, a hardware problem, etc.).

  Any help with this is really appreciated!

  Mac Pro Mid 2012
  12-core 2.4 GHz Intel Xeon | 48 GB 1333 MHz DDR3 ECC | ATI Radeon HD 5770 | 500 GB SSD
  PCI: Sonnet Tempo SATA E4P | CalDigit Super Speed PCI Express USB 3.0

  Evan Griffin replied 13 years, 1 month ago 1 Member · 0 Replies
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