Question about impact to audio sync.

[Imy]

Hi,

Quick question folks.

I'm backing up one of my NTSC DVDs (29fps) to x264 using AVIsynth and XmediaRecode. I'm not sure of any other tools which will allow me to import an AVS file. I created a d2v file with demuxed audio using DGindex. I'm using the Tdecminate and TFM to revert the footage back to 24p.

The demuxed audio AC3 filename states DELAY -33. My intention is to import the AVS file and AC3 audio into Xmediarecode to convert to x264. I will be maintaining the original audio format therefore do not intend to convert it, just copy it across. The problem is that under the audio tab there is no field to set the audio delay.

I did try going ahead with the encode without setting an audio delay. During playback the audio seems fine although the delay of -33 seems very minimal. It's hard to tell as it's an anime DVD that I am encoding.

How will the audio be impacted in this scenario?

Should I just encode the video only and then use a muxing tool which gives the option to set an audio delay?

Are there any other encoders like XmediaRecode that support AVISYNTH files?

[sneaker]

Instead of doing a negative delay on audio you can also just delay the video by e.g. duplicating the very first frame in AviSynth:
DuplicateFrame(0)

At 24 fps 1 frame is shown 41,7ms so difference then is only 8,7ms. Often with AC3 we have 5ms encoder delay. So then really only 3,7ms delay remain which is good enough. (Even 33ms is often good enough. Source probably isn't that exact anyways.)

[Imy]

Forget for a moment that I am reverting to 24p. For arguments sake if I left the framerate untouched and imported my avs and ac3 files into XmediaRecode, would the software know to apply an audio delay of -33 from referring to the filename?

Mediainfo-ing the source vob file states there is an audio delay of -33.

[sneaker]

Probably not but I haven't tested. If anything it would just read from the file name. You could easily test by changing the filename to e.g. "whatever DELAY -5000.ac3" and then look whether or not the audio is 5 seconds off.

[poisondeathray]

Are there any other encoders like XmediaRecode that support AVISYNTH files?

You can try megui. It automatically enters this info from the audio file name

[Imy]

Are there any other encoders like XmediaRecode that support AVISYNTH files?

You can try megui. It automatically enters this info from the audio file name

You're right megui supports avs files however I don't know how to configure it to copy the source audio instead of encoding it.

[manono]

Assuming you used DVDDecrypter to decrypt the DVD to the hard drive, you can ignore that -33ms delay. It's a known bug in DVDDecrypter. The delay is really 0ms.

[Imy]

Assuming you used DVDDecrypter to decrypt the DVD to the hard drive, you can ignore that -33ms delay. It's a known bug in DVDDecrypter. The delay is really 0ms.

I did use DVDDecrypter to decrypt the DVD to the hard drive however I used DGindex to create a d2v file and when it demuxed the audio the AC3 audio file name stated a delay of -33.

Is DGindex ok?