Missing file AC3filter.acm after AC3Filter 1.63b install

I have a Sony HDD based camcorder that records in MPEG2-PS and AC3 audio. I also have a copy of Vegas Pro 8 which prompted me to install AC3Filter as there is no native support in XP. Everything worked fine with camcorder video editing.

I recently bought a TV with USB record function and this creates files in the same format as the Camcorder, all was fine until I was given an XVid with AC3 sound [thanks to a friend who provided it after I failed to record a program I wanted to watch]. I tried to use Sony Vegas to create an MPEG file that will play on the TV however Sony Vegas will not recognise the AC3 audio [nor will Vdub-MP3] in the XVid.

This prompted me to get a copy of GSPOT and the ‘list codecs and filters’ function tells me that;

ACM Base msacm.ac3filter ** Missing file: ac3filter.acm

I have found 2 copies of the file ac3filter.acm, one is in “Program Files\AC3Filter” the other in “Windows\SYSTEM32”

I have also created some other XVid and DivX files with AC3 audio using Auto Gordian Knot and Sony Vegas will not recognise the audio in those files either.

What have I done wrong?

Try these .
http://www.videohelp.com/tools/AC3_ACM_Decompressor
http://www.videohelp.com/tools/Lame_MP3

Thanks t0nee1,

The AC3_ACM decompressor has not removed the error from GSPOT but it does allow Vegas to ‘see’ the audio. Unfortunately the audio is a full 7 minutes longer than the video, it is also incredably slow at analysing it and providing the peak graph. Is this normal for AC3 audio in an XVid?

I guess the problem is not totally cured, otherwise GSPOT would not still be complaining…

Just timed the first opening of an Xvid with Vegas 8 and we’re looking at 2 hours and 15 minutes to open a 30 minute Xvid file. That said Vegas is only able to use 1 core, could it be that the AC3 ACM codec is only single core capable?

As I said in my earlier post, the audio is 37 minutes, the video is 30 minutes in the AC3 file. I used Auto GK to replace the AC3 audio with MP3 audio and the times of both video and audio are the same in the MP3 based file.

2 hours and 15 minutes to [I]open[/I] a 30 minute Xvid file.

What the!..Are you trying to create a DVD compliant file from the AVI/Xvid?..
Try something else, if that’s the case…ConvertxtoDVD, DVDflick, AVStoDVD etc…
But first you’re going to have to [I]try[/I] and fix that out-of-sync issue…If the audio is constantly off, try with Virtualdub->Audio -> Interleaving -> Audio Skew Correction.
With AviDemux, use the ‘Audio’ shift tool…
With AVIMux gui, import the AVI and pick the audio-> type in the delay in(ms) and save new avi…Hope it helps…

Yeah, that’s what I thought…

Sadly no this was Vegas building the ‘peak’ graph for the audio tracks. Not sure if you’re familiar with Vegas, but it shows a timeline along the top, then puts frames of video under that to represent the video stream, finally a representation of the audio is below that.

This audio representation is the standard ‘wavy line’ style of showing audio. Before Vegas can display this it analyses the audio to build the line. It is this process of analysis that takes the time. A similar Xvid with MP3 audio opens in a matter of seconds.

The audio in the AC3 file wasn’t out of sync, just longer by 7 minutes, which was represented by a straight line indcating silence. The MP3 audio had the correct time length - even though it was created from the original with AC3 audio and rebuilt by AutoGK…???

Me thinks that Vegas doesn’t cope well with avi containers and AC3 audio. Possibly because of a bug in the codec, but equally likely is a bug in Vegas or the fact that the 2 products just don’t play nicely.

Any clues…? Know a different/better AC3 ACM codec?