AC3 and CCE Question

[Maikeru-sama]

Is there a plugin that I need to load in my AviSynth Script when the AVI file has AC3 Audio?

I have an MKV and I Re-Encoded using:
Video:lavc mpeg4 codec
Audioac lavc -lavcopts acodec=ac3:abitrate=128

Now, the AVI file that was rendered was perfect. The problem I encounter is when I drag the Avisynth Script into CCE.

<AVISYNTH>
AVISource("C:\input.avi")
LanczosResize(720,368,0,1,600,336)
AddBorders(0,56,0,56)
ConvertToYUY2()
</AVISYNTH>

I don't get an error but the number of frames and movie time shown in CCE is way short of what it should be, which always indicates an error with the AviSynth Script. Now, when I drag the AVI file into CCE, everything is fine.

Also, just for grins, I Re-Encoded the Audio using mencoder to MP3 and it worked with Avisynth:
-oac mp3lame -lameopts cbr:br=128:mode=0

What am I missing here for AVI files with AC3 Audio?

Also, I know you all will say just Re-Encode the audio to MP3 the first time, but sometimes I get errors doing that depending on how the file was Encoded. The AC3 Codec is very consistent and have not ran into any errors while Re-Encoding MKV files.

[manono]

Hi-

What am I missing here for AVI files with AC3 Audio?

You don't use any script in CCE that still contains the audio. Either disable it or remove it entirely.

For a better understanding of anything that might be wrong with a script, open it in VDub(Mod) to see if it's OK, before then opening the script in CCE. It'll give you a better error message. If the AC3 audio is still in the video, I suspect that's the reason.

Also, I know you all will say just Re-Encode the audio to MP3 the first time,

It would be silly for anyone to say that about AC3 audio if the intended output is for DVD.

Is there a plugin that I need to load in my AviSynth Script when the AVI file has AC3 Audio?

Yeah, you can try NicAudio.dll:

http://avisynth.org/warpenterprises/files/nicaudio_20070821.zip

[Maikeru-sama]

Thanks for the response manono.

I want to make sure I understand you as I have a .Net Application that streamlines all of my conversions and based on what you are saying, I am going to have to change it, which fine.

I have been using CCE for about a year and when I Encode, I always use Avisynth and the AVI File always has the Audio and Video in it.

So are you saying that my AVI file should not have the Audio in it, only the Video?

If yes, I assume I would just do "-oac null" when I just want the Video and "-vo null" when I want to just get the Audio?

Also, what is the NicAudio Plugin for? I would just assume that I would just use Mencoder to Re-Encode the audio to AC3 ?

[manono]

Hi-

So are you saying that my AVI file should not have the Audio in it, only the Video?

Yes, that's what I'm saying. Either remove it or disable it. Why invite trouble? CCE is an MPEG-2 encoder. Leave any audio reencoding to a more specialized program.

If yes, I assume I would just do "-oac null" when I just want the Video and "-vo null" when I want to just get the Audio?

What's that? Mencoder gibberish? I've never used mencoder. I would disable it in the script like so:

AVISource("C:\input.avi",False)

Also, what is the NicAudio Plugin for? I would just assume that I would just use Mencoder to Re-Encode the audio to AC3 ?

You asked how to handle AC3 audio within AviSynth. Like I said, I know nothing about mencoder. Are you trying to kill 2 birds with one stone by asking about both CCE and mencoder? I thought your original question concerned CCE only. Also, I don't quite understand why you have to convert the MKV to AVI before then sending the AVI to CCE. Isn't that extra work creating an AVI inferior to the source? But I keep as far away as possible from MKVs, so there's a good chance I don't understand that 2-step process either.

[45tripp]

(your post was a bit confusing)

first off,
install ac3acm,
then you won't have the 'problem' with cce.

nicaudio is to specifically import ac3 audio (among others) into avisynth.
you don't need it now.

not my preferred method but i'll make the minimal changes to it:

1. with mencoder use this for the video side of it

-ovc lavc -lavcopts vcodec=mpeg4:vqscale=2:mbd=2:trell

2. demux the ac3 audio from your .avi
several options, like vdub,
or ffmpeg for commandline

ffmpeg -i input.avi -vn -acodec copy input.ac3

3. change your avisynth script:

AVISource("C:\input.avi", false)
LanczosResize(720,368,0,1,600,336)
AddBorders(0,56,0,56)
ConvertToYUY2()

4.encode with cce

5.take elementary mpeg2 from cce, and ac3 audio from avi demux, and author.

[Maikeru-sama]

45Tripp, thanks for the response.

I just installed the AC3 ACM codec and CCE accepted the Avisynth Script.

[45tripp]

that was just the niggle,

i hope you took the procedural advise on board.

gl