3 Replies Latest reply on Jan 14, 2011 8:54 AM by nealeh

    Preset for iPhone 4 720p?  Pic and sound drift out of sync

    EddyKilowatt

      Hi Everyone...

       

      New user here, running PrE 9, newly installed on an HP5100 Core2 Quad desktop, with 4 GB memory and ATI 4850 graphics, under Vista Home Premium.

       

      I bought PrE to import and edit H.264 video from an iPhone 4, and add separately recorded sound.

       

      I don't see any project presets in PrE 9 which correspond to the iPhone's video specs, which I think are...

       

        1280 x 720 P

         AVC video codec, MOV container

         29.97 Hz framerate

         AAC audio codec

         44.1 kHz audio sample rate

         etc...

       

      ... at least according to a MediaInfo report on this blog:

      http://realworldvideocompression.com/rwvc/2010/6/29/details-on-iphone-4-video.html .

       

      The separate sound is recorded on a Zoom H2 as 320 kbit MP3.

       

      I don't see any PrE presets that have 29.97 Hz video and 44.1 kHz audio.    I've tried both "AVCHD Lite 30p", which has a 29.97 Hz framerate, and "Flip Mino HD 30p", which has a 30.00 Hz framerate.  Both projects allowed me to import and play the iPhone video, but... in the Monitor, what I observe is that the picture gradually drifts ahead of the sound, by about 1-2 seconds over the course of the 6-minute clip.   This is kind of a show stopper since the video is of a violinist with an active bow arm.

       

      Importing and playing the Zoom MP3 sound works also.  Interestingly, the MP3 audio remains exactly synchronized with the .MOV audio over the whole clip... it seems to be the video part that gradually "gets ahead".

       

      I feel sure this is some beginner's mistake... can anybody suggest what I might be doing or configuring wrong?  Does anyone have a Preset that they know works with iPhone 4 720P video?

       

      thanks,

      Eddy