audio and video out of sync in premiere pro 2

[Carroll Rogers]

My audio and video is out of sync on the timeline in premiere pro2. When i play the video file in windows media player there is not sync problems. i can't find any solution that i can apply inside premiere pro 2. this is a early version of premiere pro. Thanks for any help in advance, Carroll

[Richard Crowley]

Where did the video file come from?
What kind of file is it?
How long is the file?
What are the specifications of the file? FPS? Audio sample rate? etc...
Is the Premiere project set to compatible specifications?
Did the file get "resampled" or otherwise tweaked on the way into Premiere?
How did you get it into Premiere?
How FAR is it out of sync?
Is it the same distance out of sync throughout the length?
If you sync it at the head, does it hold, or does it drift out of sync?

[Carroll Rogers]

thanks
i imported the file from a canon xha1s in hdv format 1440x1080 through firewire. the timeline is a cut from a video file about 44 min. long. i can only see the last 30 sec. of any close up of faces. the timeline is 6 min. long. i did increase the the audio level by2.0 db it was not modified before i put it on the time line.

[Richard Crowley]

The horizontal and vertical pixel dimensions are not relevant to the issue.
What IS relevant is FPS (frames per second), audio sample rate, etc. etc.
Remember that you must match the specifications of the video clip and the Premiere project.
Are you able to answer any of the other questions?
So far, the information provided is insufficient to try to diagnose the problem.

[Carroll Rogers]

thanks

the frame rate is 29.97
source audio 48000hz compressed stereo
project audio 48000hz 32 pt floating point stereo
average data rate 3.2mb/sec.
sample rate 48000 samples/sec.
i used the preset for hdv 1080i 30 60i
i only have a good close up of the last 30 sec. of video can't determine audio sync at the beginning

[Rick Reineke]

Slightly off topic, but 'Media Info' is a great utility for analyzing video/audio files. .Lists all the pertinent file information.. free.
https://mediaarea.net/en/MediaInfo

[Richard Crowley]

Originally Posted by Carroll Rogers

i only have a good close up of the last 30 sec. of video can't determine audio sync at the beginning

Then pull it up to sync for the last 30 seconds and you are done.

[Don Palomaki]

How are you evaluating the video and audio sync?
What monitoring system are you using to judge?
Is it a fixed offset, or an amount that varies over time in a single clip?

Note that if audio and video travel via separate paths to separate display devices there can be a fixed shift due to latency in the different signal paths; e.g., the sound may make it out of a computer sound card before the video makes it out of a video display device. THis is even is the file is spot on. Sync is generally kept if the same device (e.g., a BM Intensity Card via HDMI to a TV) is used to output both audio and video.

At the source level, sound travels much slower than light, so audio lags lip sync by abut one frame for every 33 feet the microphone is from the person speaking. (Does not sound like your issue though.)

[Bob Hart]

Richard.


Premiere Pro 2 used to do this to me unless I converted the HDV files from m2t ( I think ) to a codec which has individual frames. In my case, I was using cineform but there will be others you could use. Please heed the advice from other folk who contribute following this comment.

My vague understanding is that the m2t files captured remain long GOP which are essentially a single key frame, which is followed by about 11 successive frames in the case of 25P/50i captures.

Each of these successive frames contains the altered image information. In editing, when you chop the vision between key frames, the system has to do some intensive processing to deal with it. There is some sort of magic beyond my comprehension goes on.

I found that when trying to cut between two sets of of video and audio tracks with original capture fles, the system would begin to slip one of the audio tracks. If for any reason I had to unlink vision and audio to pull audio along under a mute cutaway, more often than not I was in trouble. Converting to cineform files fixed that problem for me. I understand that the system has to do a lot of work dealing with the m2t files.

You may find that rendering the clips before you export helps. If "use render files" or some similar option is offered in the export menu, then selecting this may assist the process.

If your exported clip is fairly long, say more than about five minutes, you might do better creating several shorter clips, exporting them, then pulling in the exported clip files into a new project. Assembling them without adding any more effects, then exporting the assembly may also assist.