Is it possible to normalise AC3 audio?

[Youngy]

I have some AC3 sountracks with low volume, is there any way I can normalise these files or amplify with some 'gain' before I remux them with my video?

Many thanks

[awlchu]

yes,

I use goldwave. You must have a directshow AC3 decoder installed for goldwave to open it. I use a 90% gain.

A tool like ffmpeggui or TMPGenc AC3 encoder is required to return the PCM (wav) audio back into AC3.

This is how I add gain to some of my AC3 audio files.

[bugster]

I use goldwave. You must have a directshow AC3 decoder installed for goldwave to open it. I use a 90% gain.

.

But that would convert 5.1 to 2.0 and you could never recover the original 5.1.

You could use HeadAc3he to extract each channel of the 5.1 Ac3 to a wav file. Then use any audio editor (like goldwave) to adjust the volume. The remaining problem is taking the 6 wav files and re-encode to 5.1 Ac3. Software to do this tends to be quite expensive, or you can use BeSweet but the resulting Ac3 files are not 100% standards compliant.

[Youngy]

Many thankx for your help guys - I'll give it a go.

Cheers

[hech54]

Me?...I'd love to normalize the "other" direction. I am so freaking tired of getting blasted with volume during action scenes and then not being able to hear the normal conversation in the next scene.

[bugster]

Me?...I'd love to normalize the "other" direction. I am so freaking tired of getting blasted with volume during action scenes and then not being able to hear the normal conversation in the next scene.

Many DVD players have a 'night' setting in the audio setup that does just this.

[hech54]

Thanks...I'll check on my newer one. I doubt my old Grundig has that.

[BJ_M]

low volume on a ac3 file is not ussually the result of not normallizing them - but what settings are used for encoding them to ac3 ..


read the excellent guide at doom9 for more info (and on the dolby web site - where the same info exists) ..

http://forum.doom9.org/showthread.php?s=15be3ad5185dd176a149c784aa2a2aee&threadid=5602...volume+AND+low

[Kurt S]

"Me?...I'd love to normalize the "other" direction. I am so freaking tired of getting blasted with volume during action scenes and then not being able to hear the normal conversation in the next scene."

This has nothing to do with normalizing. Normalizing will bring all the audio up so the highest peak in the audio will be at 100%. What you want is known as compression and/or limiting. This will bring the quieter parts up louder and limit the loud parts to a certain level so there isn't such a difference between the quite and loud parts.