3 Replies Latest reply on May 7, 2011 10:08 AM by Colin-B

    MTS Files appear to skip frames at clip transitions?

    dave@lihubbards.com

      My Canon Vixia HF S200 creates multiple sequentially numberd MTS files for long sequences.

       

      Snapping them together in Premier Pro CS5 yields a 'jump' between clips, as if frames were missing.

       

      Now, sombody on another forum insisted that there were no frames missing from the MTS files, and that re-muxing them would prove it.  So I did download 'tsMuxer' a free muxer, and combined a few into a single m2ts file and indeed the 'jump' vanished at the point where the previous 2 would have joined!

       

      So....  Any ideas?  Some setting?  Frame rate?

       

      Thanks,

      Dave

        • 1. Re: MTS Files appear to skip frames at clip transitions?
          Jim_Simon Level 8

          Copy the entire top level folder from the camera to your hard drive, not just the .mts files.  Then use Premiere Pro's Media Browser feature to import the clips.  Doing it that way should resolve the problem.

          • 2. Re: MTS Files appear to skip frames at clip transitions?
            dave@lihubbards.com Level 1

            That worked, thanks!

             

            So it appears that the camera is not actually creating individual complete MTS files with all the embedded structures, but they are really just chunks of one larger MTS object, broken up to stay under the 2 GB limit of some file systems?  Thus the media browser and other tools that know this combine them correctly?

             

            Whereas trying to look at them as individual complete MTS files must confuse some software, I'm guessing that Premiere, and other viewers that I played with, seem to have to skip some stuff in later files (not the first) to try and get in sync with the data stream or something?

             

            Just wondering how that is really working under the covers...

            • 3. Re: MTS Files appear to skip frames at clip transitions?
              Colin-B Level 1

              dave@lihubbards.com wrote:

               

              Whereas trying to look at them as individual complete MTS files must confuse some software, I'm guessing that Premiere, and other viewers that I played with, seem to have to skip some stuff in later files (not the first) to try and get in sync with the data stream or something?

               

               

              You're quite right that the camera splits the files at arbitrary positions. This means that each split file may start and/or end in the middle of a GOP or even the middle of a frame. So if Premiere is not provided with the information about whether the files are part of a split sequence then it must treat each file as a separate standalone file - and each file therefore probably looks like it has leading and trailing unusable data that can only be discarded.

               

              Supplying the whole folder structure allows Premiere to ascertain how the files were split, and therefore how to seemlessly join them again.