ReplayGain for FLAC? Options

[Ardax]

I don't know if there's been any work in this direction at all lately, but is anyone doing replaygain for flac? Could the format support it?

Thanks!

[jcoalson]

Originally posted by Ardax
I don't know if there's been any work in this direction at all lately, but is anyone doing replaygain for flac?  Could the format support it?

Thanks!

The plan is to have a FLAC metadata block for it, and have the command-line encoder optionally calculate it for you. Or an external tool could calculate it and write it to the tag.

Josh

[kritip]

Just a quickie,

I know this idea hasn't been implimented yet but it is one of the few things which has put me off going lossless for all my CD's because the volume differences real get annoying.

Here's my question,

Could this Meta data be added to existing FLAC files or would they need to be uncompressed and then recompressed by a newer version of the encoder.

If the data can just be added to existing FLACs without this intermediate stage, i'll start my archiving now and wait for this feature to be avaliable, otherwise i'll hold off as i won't fancy decompressing and then recompressing all the dataor would the the adition of the meta data requier the whole file to be re-encoded by the meta data editor anyway?

Cheers for any response, hope you don't feel im nagging or anythin, just wonderin wether it's worth starting the Mamouth task of archiving my CD's or holding off for a while.

Kristian Tippins

[jcoalson]

Originally posted by kritip
Just a quickie,

Could this Meta data be added to existing FLAC files or would they need to be uncompressed and then recompressed by a newer version of the encoder. 

Kristian Tippins

Speaking for FLAC...

The next release will have a metadata editor to do what you describe but that is a month or two away. That is also the earliest that a replaygain tag will be available. Inserting a tag will still require the file to be rewritten (but not decoded/re-encoded) because metadata is variable length and at the front of the file.

To save even the rewrite-file step, you could encode now with a padding block of sufficient size. Then tags can be inserted into the padding without rewriting the file.

Replaygain should only occupy a few tens of bytes, but plan ahead. The next release should also support vorbis-style comment tags which you may also want to use.

Josh

[kritip]

Ok, thanks for that, i'll go with it now then, thanks a lot for your reponse Josh. Its much appreciated.

Kristian Tippins

[Ardax]

Ooh, I hadn't even noticed that flac allowed for writing a padding block! With handy tags coming down the pipe, that will make flac REALLY nice for lossless encodings.

Just out of curiosity though: Wouldn't calculating the replay gain necessitate decoding the entire file? (That's still much less expensive than a full decode/encode cycle, I understand.)

At any rate, I'm sure that there's many of us who are patiently awaiting the next version of flac. Thanks.

One thing I've noticed with my flac files though: When I run metaflac on any of them, I always get an "Error: short count reading metadata block data." The files test (and decode) fine though. This is running under Win XP on an AMD Duron.

[jcoalson]

Originally posted by Ardax

Just out of curiosity though: Wouldn't calculating the replay gain necessitate decoding the entire file?  (That's still much less expensive than a full decode/encode cycle, I understand.)

Yeah, good point, hadn't occurred to me.

Originally posted by Ardax

One thing I've noticed with my flac files though: When I run metaflac on any of them, I always get an "Error: short count reading metadata block data."  The files test (and decode) fine though.  This is running under Win XP on an AMD Duron.

hmm, haven't seen that. can you submit a bug to the sourceforge tracker? thanks

http://sourceforge.net/tracker/?group_id=13478&atid=113478

Josh