Will I get audio sync problems if I do this?

[mojo2185]

I have 2 AVI files encoded in DivX3. First, I need to join the two files (using virtual dub guide on this site), and then I need to cram the joined file onto a (s)vcd, most likely an X(S)VCD. While encoding to the X(S)VCD, I also need to change the file to NTSC. Question is, during this process, should I expect to get any audio sync problems? Would it be easier to change the framerate while the file is still an AVI before encoding, or just do it at encoding?

So basically I want to do this, all in one shot.
step1: merge the two files.
step2: change PAL-> NTSC and set other options for encode to XVCD
step3: take ready to burn XVCD (that is now NTSC) and burn it.

Is this ^ possible?

One more thing, when i use the bitrate calculator, where would that bitrate go if I do VBR? Is it the min bitrate, the max, or the average?

[jamesbond1960]

You will for sure have audio sync problems. The avi files must be converted to NTSC 1st as well as the audio files. This will require you to separte the audio from each avi then convert it then agin the same for the next avi file and then join them and then encode the batch... Bit rate I can't help you with. As far as I know teh encoder can calculate the bit rate for you and I'd use CBR instead of VBR its a little easier and takes less time. VBR is good very good actually but I hate the time it takes to encode......I can give you more info on converting PAL avi to NTSC avi just e-mail me

Archie(doctorag2003@yahoo.com)

By the way I'm gonna complete a guide for this real soon as I found it works really good and I have to thank a really cool guy out there who helped me find this method........

[Hardcoreruss]

In my experience whenever avi files are joined I ALWAYS get audio sync problems. Maybe it is just me.

[mojo2185]

The avi files must be converted to NTSC 1st as well as the audio files. This will require you to separate the audio from each avi then convert it then again the same for the next avi file and then join them and then encode the batch...

So basically I should, separate the audio from the video of the two AVI files. Then change the audio/video to NTSC for both files. Then combine the two audio files, combine the two video files. Load the audio file, load the vid file and finally encode? What's the best way to join the audio files from the AVI (what program should I use)?

Thanks


EDIT: So far it looks like it worked great. I haven't encoded the movie in full yet, but some samples came out fine, no sync probs.

[DJRumpy]

You should merge them in VDub before encoding. If the files contain 5.1 AC3 audio, then you will need to repair the audio with AC3Fix after extracting it in VirtualDub (make sure you set the audio to 'Direct Stream Copy'. If you have AC3 audio and you do not run AC3Fix, you will encounter audio sync problems.

If your audio is NOT AC3, then you can simply merge them, and encode.

I would suggest you use AVISynth 2.5 to do this becaue it is faster than VirtualDub, and it will also resample your audio. AVISynth can resample the audio, if needed, to 44.1Khz on the fly and change your video framerate all in one step. You script would look like this:

AVISource("YourMovieFilename.AVI")
LanczosResize(480,480)
ResampleAudio(44100)
AssumeFPS(23.976,True)
ConvertToYUY2()

Correct the first line, so it has the correct AVI filename. The second line has your desired resolution. Put whatever resolution you want on that line. Save the above text in NOTEPAD, and put it in the same directory as your .AVI file. Call it anything you like, and give it a .AVS extension. Drop the .AVS file onto whatever encoder your using.

If your joined AVI's have AC3 audio, then modify your first line, so it looks lke this:

AVISource("movie.avi",False)

The FALSE parameter will tell AVISynth to ignore the audio stream. Convert your AC3 audio with AC3Machine. It will perform the PAL to NTSC conversion, and retain the full 5.1 sound.