Mini How To - Increase Your AC3 Volume

sumeshkri · Member Joined: 12 Nov 2007 Location: India

Hai dear soopafresh,
thank you for your continuous support on this forum.
i have been looking on this thread for my poblem to solve.
if we read from the beginning, it is somewhat confusing now. what to use and how to, it is not known, as far as i am concerned because of the mess of the things. i am only a common man. desn't know the tecs. so please advice me on this.
I have got burned a dvd(film). when i play it on the dvd player the sound is too low that i have to raise the volume of the TV to the maximum to hear the vocals of the characters where as there is no problem for the sounds of vehicles etc. i want to increase the volume. for that i have got instructions from you that first i have to demultiplex the vob files. then take the audio file to ------ then comes the confusion., your first instruction was to use the ac3gain. now it says use ac3normalizer. and you said that NET 1.1 is needed. and also the avisynth 2.57. can you sum up the instructions please? i searched the microsoft site to get the NET.1.1 file it is too big. it says it is of 100 mb.Is it so? can you give a link to the files needed to be downloaded? is it possible for you to give a folder in which all the necessary components are included on this thread. thanks in advance.

Soopafresh · Craptastic Joined: 01 Jan 2004 Location: United States

Read the other post and try Tmpgenc DVD Author with the "normalize audio" function. That will be the easiest way, I believe.

sumeshkri · Member Joined: 12 Nov 2007 Location: India

thanks a lot i will try that

VirtualDoobMon · Member Joined: 15 May 2005 Location: ||*||

Hi Soopafresh,

This works amazing! Is there anyway you could create a batch so it extracts ac3 from avi then runs a script? If there is any plan to merge avi_gain & ac3gain I can't wait, that would be awesome. I think most people would agree with these merged, it would eliminate the need for other tools such as divfix etc (as mencoder -forceidx fixes most issues for me). For my particular need with these merged, i could have a single script and depending if mp3 or ac3, it could fix index issues and most important fix/increase the audio quality.

Thanks again

Soopafresh · Craptastic Joined: 01 Jan 2004 Location: United States

This works amazing! Is there anyway you could create a batch so it extracts ac3 from avi then runs a script?

Thanks, man.

What do you want to accomplish by doing that ?

VirtualDoobMon · Member Joined: 15 May 2005 Location: ||*||

All my backups are ac3 5.1 in avi that i stream to my living room io-data unit and output to my receiver. I now have another IO unit at the cottage (no receiver) and have found the 5.1>stereo not that good -- quiet/loud. I plan on backing up my collection to a portable HDD for use at the cottage but would like them as 2ch ac3 (I know ffmpeg -ac 2 -acodec ac3) but i want them normalized thru your script.

Before i found this post, i was thinking about batch converting everything to mp3 and calling avi-gain or maybe just use mencoder -af volnorm,channels=2 ..

Truth is i don't know that much about audio and i was hoping to avoid some of the learning curve by using your 1.5 or 1.8 profiles...And of course avoid the manual demux/mux of accomplishing this.

Thanks again!

Soopafresh · Craptastic Joined: 01 Jan 2004 Location: United States

Gotcha. So you want this:

AVI w/ 5.1 ---> AVI w/ audio Normalized and Downmixed to 2.0

Should be pretty easy. I'll have something for you this evening.

What I'm thinking would work is a modification of the AVI_Gain script, where the AC3 is demuxed, converted to stereo WAV, then normalized and dynamic range limited, then converted back to 2 channel AC3 and remuxed with the video.

Edit: Try this http://www.mediafire.com/?sharekey=3b2c379969a8c01ad2db6fb9a8902bda

Note that during the remux you might see a "Invalid and Inefficient VFW B Frame" error message. Don't worry about it. Surprisingly, this was harder than I thought it would be. The remuxing was a PITA, and the only thing that worked was FFmpeg. I also had to use a different version of ffmpeg for the demuxing.

Just test it out on one or two files to see if it plays properly on your DVD player.

VirtualDoobMon · Member Joined: 15 May 2005 Location: ||*||

Worked like a charm thank you! Didn't enounter any issues one the first few and the playback sounds awesome. You da Man!

I have gone thru probably about 1/3 of my collection now and have yet to experience any issues and doubt i will.
Soopafresh, Thank you very much for helping me on this task. Really really appreciate it.

yuriapt22 · Member Joined: 01 Mar 2009 Location: Russian Federation

I use AC3GAINv4 to increase AC3 volume.Everything is all right but in result I get mono file instead stereo.Please help me.

Soopafresh · Craptastic Joined: 01 Jan 2004 Location: United States

1)Can you check your original AC3 file to see if maybe it is mono?

2) For a test, run AC3gain on the Output file again. Look at what the batch file says.

First Run on Original File - 6 channels (5.1)

Running Ac3Gain again on the normalized output file - 6 Channels again

halsboss · Member Joined: 13 Jan 2004 Location: Australia

Soopafresh, if we have AVI files with arbitrary audio encoding, would you pls be so kind as to confirm if this (adapted from an older one of yours) provides a similar outcome in terms of gaining and DRCing. Drag'n'drop an AVI on the .bat file or call it from another .bat like

yuriapt22 · Member Joined: 01 Mar 2009 Location: Russian Federation