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View Full Version : Is there a way to boost audio in an mpeg



Pro-289
06-18-2003, 01:41 PM
Is there a way to boost the audio in an .mpg without ripping it apart before I burn to an SVCD? Or would I have to de-mux it, boost the .mp2 with something like mp3gain, if it'll work, and then mux it back?

captain_video
06-18-2003, 09:40 PM
I don't know if it's even possible, although it certainly sounds feasible. I would imagine that you'd have to separate the audio stream in order to boost the amplitude. I'd be interested in knowing the answer to this myself. I notice that all of my DVDs culled from PPVs tend to be much softer in sound volume than the original recording, causing me to boost the volume during playback. It would be nice if I could adjust the volume prior to authoring a DVD to compensate for the loss.

SR712
06-18-2003, 09:57 PM
If the mpeg is demuxed, you can take that .mpa file into an audio program, such as Sound Forge, raise the levels, and then mux it together again. I used to do this all the time a few years ago prior to making production masters in DVD Maestro. This worked well for me, as Maestro needed demuxed files, anyway. I'm not sure, but I think Sound Forge need an mpeg plug-in. It's been a while.

Pro-289
06-19-2003, 02:22 PM
Yea, I tried that in Sound Forge. It wouldn't let me save to MP2. So I saved it as WAV and used another converter to go from WAV->MP2. But what I don't like about doing this is that it re-encodes the audio. Making it not the same quality as the original.

I tried MP3Gain, but it said it doesn't work for MP2s. That would be nice, since it doesn't re-encode anything, just adjusts the resulting output volume. I think I read somewhere also that when a certain software, forgot which, converts AC3 to MP2, there's a bug to where it lowers the volume. Maybe that's what's happening with PPV. Or that they're not really using DD5.1, but AC3 2/0 like I got off something from HBO, which I think is only digital FL FR, but still needs to be converted to MP2. Not sure though.

Which software really uses .M2A extentions that TyTool makes anyway? Shouldn't they be .MP2, since that's what they really are? Sound Forge or Tmpgenc don't even know about the .M2A extention, although it will load it if it's Mpeg-1 and not AC3.

shadowramy15
06-19-2003, 03:37 PM
Try BeSweet, click the boost button then manual and raise the levels.

Of course you'll have to split the video and audio then remux.