how to synch audio to video or video to audio ?

[kenma]

I'm just authoring a DVD with DVDMaestro.

The DVD shall be: one video (MPEG2-PAL) with two audio-tracks (ac3 PAL), but the files are having different lengths, difference is only in seconds, one is a little longer than the video, it starts earlier and one is a little shorter than the video so there is a little delay while playing. How do I fix the files in synch ?
The files are all in the same format (PAL).
Is there a tool to create synched audio/video-tracks ?
Is it possible to create synched audio/video-tracks with DVDMaestro ?

[oddyseus]

If audio is of the same source as the video, u can right click on the audio track and select Create Sync Audio. In the window that opens assign the wanted audio to the video and it should be croped in sync and placed for u in the timeline.

This will work only if the embedded timecodes in audio and video r the same. If not u will most probably get silent audio instead.

If this won't work I suggest to place a black bmp infront of the actual video with a proper duration that would made bmp+video=longer audio.

Place the longer audio in place, zoom to the extreme select a scene that has people talking and by moving the audio stream try to lip sync them.

[kenma]

Originally posted by oddyseus

If this won't work I suggest to place a black bmp infront of the actual video with a proper duration that would made bmp+video=longer audio.


what's the best way adding black frames infront of the video ? Is it possible to do that in DVDMaestro ?

[oddyseus]

Make a 720x576 black bmp (PAL) or 720x480 (NTSC) in paint, Photoshop or anything that can build bmp images, import it in Maestro, place it like a m2v in the timeline, drag the right edge to the end timecode lets say 5 secs. After it u can add the video.

[kenma]

The problem is, that both Audio-Tracks are longer than the video! I wrote wrong in the initiate posting about this problem.

The project looks like this if I take the black bmp's:

B = Black BMP
* = Video/Audio-Block
' = Marker (Start/End)

12345678910111213141516171819202122232425262728293031323334353637
Video (m2v): BBBB*******************************************
video-start at: 13 (after B)
Audio1(ac3): ***********************************************
video-start at: 13 (after B)
Audio2(ac3): ****************************************************
video-start at: 20

Audio1 is two frames longer than video, I made a test with ifoedit and the expectation with an audio-delay of 80ms has been confirmed, the video/audio was in synch. So, I found the correct setting for Audio1.
Audio2 is 6 seconds (6000ms) longer than video and the difference to the video-start is ~2 secs. That's why the video-start at Audio2 is at a different position!

As long as I can't move the video-block in dvdmaestro, I can't imagine how to correct this problem directly in dvdmaestro.

I think that the best would be cutting the audio-tracks, but as long as it is an ac3-file I wouldn't know how! Which tool is able to cut ac3-files and possible to monitor back to video if the cutting possition is the correct one ? It must be a tool able to cut six waves at a time or directly ac3!

The only tool i found, beeing helpful was ifoedit, because of the directly enterable delay (ms) per audio-track. I think it would be possible to master the dvd with ifoedit, setting the correct delays and going with it, but I want to have a menu and chapters at special positions on that dvd! And I wanted to do that with dvdmaestro!

There is an idea, driving around in my head, about what oddyseus said earlier:
"This will work only if the embedded timecodes in audio and video r the same. If not u will most probably get silent audio instead."

If I take ifoedit mastering the dvd with the correct delay setting for the audio-tracks, will ifoedit generate a new "corrected" timecode to the files ? And would it be possible to extract the video-/audio-data with a dvd-ripper including the right timecode to import these files back to dvdmaestro to build up the menu and chapter-points ?
As it is time-consuming I will test that later, maybe anyone could tell me if this would be a possible "good" idea and which tools and tool-settings to take to go on ?

[oddyseus]

Now that we know that the 2nd audio is 6 secs longer than the video I think its easier to accomplish the task.

Insert a 8 sec bmp still in front of the main video. Now u can align both audio without a problem.

Take a note that u can drag audio along its track. Its isn't a requirement for it to start at zero. Only video is forced to start at zero.

Vitec Mpg2Pro suite has a utility to cut ac3 without reencoding, but I think that it isn't available anymore.

[kenma]

@oddyseus
Thank you for your help! I'll try that!