Convert replaygain to iTunes/iPod volume?, Can this be done & does it make sense? Options

[davelasker]

I'm an experienced Windows programmer, but a digital audio newbie and also a new iPod owner. I'm trying to normalize playback volume through my iPod.

I tried Apple's Sound Check and didn't like the results. Just turning Sound Check on in the iPod makes its output sound terrible, even before any normalization was done in iTunes.

I'm looking for something like iVolume (Mac-only AFAIK) for Windows that manipulates the volume for each track. I'd like to take a crack at building a fb2k plug-in to do this.

I looked at foo_pod, but it seems they are going the Sound Check route. I'm suffering from the delusion that manipulating volume will give better results than Sound Check. Any truth to this?

Info I'm looking for includes:
a) Where & how is the Volume stored in an Apple .mp4 file? Or is it in the iTunes DB? Any pointers to docs on this would be apprecated.
b) Or would it be easier to use the QuickTime API to set the volume?
c) In either case, how are the replaygain db levels mapped to Apple volume levels???
d) Any other forums where I should be asking this question?

Thanks for the help!

Dave

This post has been edited by davelasker: Aug 1 2004, 22:40

[JohanDeBock]

This is something I just made for people that still use iTunes for their ipod management, but also want to use Replay Gain.

http://uclc.info/ipod/

Usage:
ipodrg.exe file.mp3 a for Album Gain
ipodrg.exe file.mp3 t for Track Gain

If it finds a Replay Gain tag AND a Sound Check tag,
it alters the Sound Check tag to match the Replay Gain value.

Thanks to Otto42, Mike Giacomelli, Aero and anyone I forgot at Hydrogenaudio for clearing out the converion formula.

I still don't know what all the values in the iTunNORM tag mean so I just replace them all with the Replay Gain value.
What I do know is that all those values seem to have an effect on the dB value given by Get Info in iTunes.

Feel free to debug, add features, ...

The rgsc program is a simple program that gives a list of all the tracks in an iTunesDB file together with their Sound Check value.
Usage:
rgsc iTunesDB

This post has been edited by JohanDeBock: Mar 22 2006, 17:13

[SNAG]

This is something I just made for people that still use iTunes for their ipod management, but also want to use Replay Gain.

http://uclc.info/ipod/

Usage:
ipodrg.exe file.mp3 a for Album Gain
ipodrg.exe file.mp3 t for Track Gain

If it finds a Replay Gain tag AND a Sound Check tag,
it alters the Sound Check tag to match the Replay Gain value.

Thanks to Otto42, Mike Giacomelli, Aero and anyone I forgot at Hydrogenaudio for clearing out the converion formula.

I still don't know what all the values in the iTunNORM tag mean so I just replace them all with the Replay Gain value.
What I do know is that all those values seem to have an effect on the dB value given by Get Info in iTunes.

Feel free to debug, add features, ...

The rgsc program is a simple program that gives a list of all the tracks in an iTunesDB file together with their Sound Check value.
Usage:
rgsc iTunesDB

Hi, thanks for the program, it's going to be a godsend to me.

Just to ask, is there any way to batch re-tag the Soundcheck files that I have? Typing the command for thousands of files is going to kill me..

Just a suggestion: It would be great if a FB2K plugin could be created to also automatically write the relevant Soundcheck values into the MP3 file(s) when RG is applied to them.