absinthe
12th October 2004, 04:18
Could someone advise me on where I'm going wrong in my sorry attempts carry a 6-channel AC3 soundtrack through a framerate conversion? I long ago gave up trying to do this and keep it in sync, and just ran it through an MPEG encoder with AviSynth to make sure it stayed in sync, but others have recently bragged that they do it all the time and the AC3 comes out oh, so much better than a stereo mp2 track.
Here's what I've tried:
1. I take the original AC3 5.1 channel sound to a PAL movie and use the BeSweet Wizard to split it to 6 mono waves. I select "WAV" in step 2 of the wizard, and "16bit (six) mono waves" in step 3. I select PAL > NTSC (25000 to 23976)" under FRC presets in step 4. The command line is basically:
BeSweet.exe -core( -input "D:\PALsound.ac3" -output "D:\channels - New - [11.10.2004] - [22.57.38]-" -6ch ) -azid( --maximize ) -ota( -r 25000 23976 )
(On a side note, I've also tried simply splitting the file into waves this same way except without the rate conversion, and then using the soundtouch command on each individual wave. But I abandoned that almost immediately because for some reason the 750 MB wave I start without comes out as only 300-and-something MB. Don't know why, but that method would take forever anyway).
2. I rename all six waves to essentially exactly the names used in the BeSweet FAQ under how to mux 6 waves to AC3. In fact, I literally copied and pasted the channels.mux file from the FAQ and just changed the drive letter to D:.
3. I used the GUI with the resulting command line:
BeSweet.exe -core( -input "d:\channels.mux" -output "d:\channels.ac3" ) -ac3enc( -b 448 )
And I do get a 6-channel AC3 track that's a few MB bigger than the one I started with (which makes sense since it's a tad longer). But it's about 8 seconds longer than the video file. Now, truth be told, I think it's impossible to tell if it's really in sync until it's muxed but I just have the absolute sinking feeling (pun intended) that it ain't. The original video (before conversion) and AC3 files were the same length.
Where oh where do I go wrong?
-abs
Here's what I've tried:
1. I take the original AC3 5.1 channel sound to a PAL movie and use the BeSweet Wizard to split it to 6 mono waves. I select "WAV" in step 2 of the wizard, and "16bit (six) mono waves" in step 3. I select PAL > NTSC (25000 to 23976)" under FRC presets in step 4. The command line is basically:
BeSweet.exe -core( -input "D:\PALsound.ac3" -output "D:\channels - New - [11.10.2004] - [22.57.38]-" -6ch ) -azid( --maximize ) -ota( -r 25000 23976 )
(On a side note, I've also tried simply splitting the file into waves this same way except without the rate conversion, and then using the soundtouch command on each individual wave. But I abandoned that almost immediately because for some reason the 750 MB wave I start without comes out as only 300-and-something MB. Don't know why, but that method would take forever anyway).
2. I rename all six waves to essentially exactly the names used in the BeSweet FAQ under how to mux 6 waves to AC3. In fact, I literally copied and pasted the channels.mux file from the FAQ and just changed the drive letter to D:.
3. I used the GUI with the resulting command line:
BeSweet.exe -core( -input "d:\channels.mux" -output "d:\channels.ac3" ) -ac3enc( -b 448 )
And I do get a 6-channel AC3 track that's a few MB bigger than the one I started with (which makes sense since it's a tad longer). But it's about 8 seconds longer than the video file. Now, truth be told, I think it's impossible to tell if it's really in sync until it's muxed but I just have the absolute sinking feeling (pun intended) that it ain't. The original video (before conversion) and AC3 files were the same length.
Where oh where do I go wrong?
-abs