6 Replies Latest reply on Apr 28, 2010 6:38 PM by vfouquereau

    Exporting to H264 using AAC input : sound skips




      Hi there,


      Let me try to get you guys all the information in one big chunk. http://forums.adobe.com/images/emoticons/happy.gif


      My computer :


      Intel Core i7 860

      8gb DDR3 RAM

      Western Digital WD5000AAKS HDD

      ATI Radeon HD4870

      ASUS P7P55D motherboard


      Windows 7 Home Premium (x64)

      Premiere Elements 8.0.1

      Everything is up to date to the latest version/driver


      The source material :


      Video :


      1920x1080 AVCHD (Panasonic HDC-HS250, REC MODE: HA1920 [Highest quality])

      177 mb


      Audio :

      Case 1 :




      Case 2 :




      Export settings (advanced) :


      Format: Quicktime

      Export Video : Yes

      Export Audio : Yes

      Video tab :

      Video Codec Section

      Video Codec: H.264

      Basic Settings Section

      Quality: 80

      Width : 1280

      Height : 720

      Frame Rate: 30

      Field Type: Progressive

      Aspect: Square Pixels

      Render at Maximum Depth : No

      Codec Settings: 24 bit

      Advanced Settings Section

      Set Key Frame Distance : Yes

      Key Frame Distance (framerate):: 24

      Optimize Stills: No

      Frame Reordering: No

      Bitrate Settings Section

      Set Bitrate : Yes

      Bitrate (kbps):: Yes, 4500


      Audio Tab :

      Audio Codec Section

      Audio Codec: AAC

      Basic Audio Settings

      Sample Rate: 48000 Hz

      Channels : Stereo


      The problem :


      It's quite simple, let’s expose with a couple of cases.


      Case 1: I use the MP3 file as the soundtrack (in the soundtrack “lane”), I export the clip. Everything is super, including audio.


      Case 2: I use the AAC file as the soundtrack. I export the clip. The audio skips beats at irregular times.


      Case 3 : I use both the MP3 and AAC file as the soundtrack. I export the clip. The audio skips beats at irregular times.


      As soon as I put an AAC file in there, the audio skipping begins. The video is fine, high quality all the way.


      What I checked :


      - The AAC file sounds perfect in every other audio program prior to encoding. The sound file is not the cause. I tried using multiple AAC and MP3 files, the problem is constant.


      - I am aware of the limits of the hardware and I know for SURE I’m not hitting them. This is not hardware related.


      - Every driver and every software is up to date.


      What’s left :


      Apart from transcoding my AAC files to MP3 every time I want to use them in movies, any idea?