10 Replies Latest reply on Mar 31, 2010 5:17 PM by Steve Grisetti

    Audio Desync if H.264 Export

    dominikr Level 1

      I'm attempting to export to H.264, specifically: QuickTime 1280x720 29.97 fps 48 kHz Stereo


      When I export, I get a file that has audio eventually desync from video, with the problem being worse later on in the file and non-existent at the start. (I'm exporting in 10 minute chunks for subsequent YouTube upload).


      Reading forums, I've tried varying my input format, but whether I use .MOV (direct from my Canon Rebel T2i), AVI, DV Type 2, and CineForm NeoScene's format I always get this audio desync issue if I export to H.264.


      I do not experience audio desync in Premiere Elements' editor itself, nor do I get it if I export to a different format (e.g. WMV).


      I'd love to be able to export to H.264 without this audio desync but I'm frankly at a loss as to what I'm doing wrong to experience this audio desync.


        • 1. Re: Audio Desync if H.264 Export
          Steve Grisetti Adobe Community Professional

          Where are you getting all of these formats that you're using as source files, d? Is your AVI captured over FireWire from a miniDV camcorder? That type of video should work flawlessly in the program.


          If these formats are all from conversions, it's possible your conversion settings aren't quite right. Ideally, when you've got the right AVI file and your project is properly set up it, there will be no red or green lines above your clips on the timeline. Is this the case with your video files?

          • 2. Re: Audio Desync if H.264 Export
            dominikr Level 1

            My original source files are from my Canon Rebel T2i. They are 720p.


            Using GSpot, it tells me these are, in native format,

            H.264 with 48 kHz sowl 16-bit signed little-endian Audio


            I can load these directly into PE8 and as long as I export into a non-QuickTime format, everything works beautifully.


            Before loading into PE8, I've attempted to convert them to AVI (Motion JPEG -- using Canon's converter), and CineForm's format (using the NeoScene Trial).


            Respective GSpot info for each:

            AVI Motion JPG

            Motion JPEG w/ PCM Audio 22.05 kHz



            CineForm 10-bit Visually Perfect HD (Wavelet) w/ PCM Audio


            I haven't figured out how to convert my source files into "DV AVI Type 2" (which from reading stickies is what I should be shooting for) -- I have Streamclip, and it only offers a 720x480 conversion, which is lower res than I'd like to work with (I'd like to stay at least 720p for this project, and in the future work at 1080p throughout).


            In the timeline:

            All my video clips, no matter what format I've used, have red lines above them. The only except are the PNGs that I've used as a title screens -- those have green lines above them.

            • 3. Re: Audio Desync if H.264 Export
              Steve Grisetti Adobe Community Professional

              You're not going to get good quality using those still camera videos directly in Premiere Elements no matter what preset you choose, d.


              You're also going to run into problems using MJPEG-AVIs.


              You'll get the best results if you use a program like Super or Quicktime Pro to convert that H.264 video to DV footage, per the FAQs to the right of this forum.


              • 4. Re: Audio Desync if H.264 Export
                dominikr Level 1

                Here's an example of what I'm seeing with the H.264-off-the-camera as input and WMV as output:



                It's not perfect, but it seems decent (at least to an untrained eye like mine).


                Which settings should I use in QuickTime Pro to convert to DV to maintain 720p?


                I tried these and it ended up scaling down to 835x480 from the original's 1280x720.


                File | Export.

                Export: Movie to DV Stream


                DV Format: DVCPRO

                Video Format: NTSC

                Scan Mode: Progessive

                Aspect Ratio: 16:9

                [Unchecked] Preserve aspect ratio using:


                I haven't tried Super, but as I have QuickTime Pro, I figure it should be able to do whatever I need (I hope)?

                • 5. Re: Audio Desync if H.264 Export
                  Steve Grisetti Adobe Community Professional

                  You should use the DV, not the DVCPro setting.


                  As I said, you'll know when you have the right format because, when you add the clip to your timeline, there will not be a red line above it.


                  Your results, by the way, look terrific! So you must be doing something right.


                  And, yes, if you have Quicktime Pro, you probably don't need Super.

                  • 6. Re: Audio Desync if H.264 Export
                    dominikr Level 1

                    I tried exporting to just DV (not DVCPRO), but QuickTime Pro again downscales to 853x480. I'll post over on the QT Pro forums and also try to give Super a try.


                    On the plus side, if I do import the downscaled file into PE8, it shows up with a gray line above it (not green, but not red either).



                    I tried Super, but it only lists 720x480 and 720x576 as valid output sizes if I select the DV output container/DV output video codec.

                    • 7. Re: Audio Desync if H.264 Export
                      dominikr Level 1

                      Doing some more research, it seems DV is only an SD format -- no HD support.


                      What editing format should I be using to edit 720p and 1080p video in Premiere Elements 8?


                      And is the fact that I'm using H.264 QuickTime as my editing format really the reason that I get audio desync when I export to H.264 (but not to any other format)?

                      • 8. Re: Audio Desync if H.264 Export
                        Steve Grisetti Adobe Community Professional

                        Ideally (and I hope Quicktime Pro supports this) you should be saving as a 1440x1080 anamorphic MPEG.


                        Then use the HDV preset in Premiere Elements. If you've converted properly, it should should up with no red line above it on the timeline -- just as the AVI did when you used the DV preset.

                        • 9. Re: Audio Desync if H.264 Export
                          dominikr Level 1

                          It doesn't.


                          QT's export options:



                          I will try MediaCoder to see if I can get QT into anamorphic MPEG, but for now it looks like just exporting to WMV instead of H.264 solves the immediate audio desync issue (though I'm a bit curious why it only shows up in exports to H.264).


                          Why 1440x1080, by the way? If I'm shooting at either 1980x1080 or 1280x720?

                          • 10. Re: Audio Desync if H.264 Export
                            Steve Grisetti Adobe Community Professional

                            Animorphic 1440x1080 means that the pixels are wider than tall, other than square.


                            A 1440x1080 animorphic image (the standard for TV and tape-based hi-def) is the same size as  1920x1080 square pixel video.