I have 10000+ flac files mostly encoded at level 6. If I want to shrink them is it possible to re-encode them to level 8 without firstly converting then to wave files or could this present me with quality or other issues???

Basically I use dbpoweramp so is it OK just to select all the flac files as source & then re-encode at level 8?


TIA

Mat

Lossless to lossless is lossless, period.

It could be tricky reencoding within the same file structure since the output file will be the same name as the input file. You don't want to decode to wav first because of poor tag support. How about reencoding to an intermediate file of a different lossless type (ape etc.) then reencoding those files to flac?

101 Error

I guess the only question is: are you using any esoteric tags that might not be preserved (buy carry useful information)... come to think of it does flac encoder preserve replay gain tags when re-encoding?

I have tags such as Artist, Album, Genre, Date & Track #. I trust these will be preserved?

Make sure to test a few; if I recall correctly the size difference between 6 and 8 isn't very big.

Did a little test and it was +/- 4% (meaning roughly 10g for every 250g)

Not sure if that would be worth it, IMHO.

those I never had trouble with while transcoding in foobar2k, and since you are using dbamp, which is a pretty solid piece of software, I don't think you'll have problems... but test on one file, just in case.

/edit: just tested and the replay gain tags are lost, though I'm not sure if it's flac encoder or fb2k that's not preserving them.

It's been a while since I did lossless-to-lossess (or any conversions other than lossless-to-AAC for my iPod) in foobar, but I seem to recall that it did transfer ReplayGain data. Even if not, you can always do a quick rescan in foobar.

The compression level of FLAC has little effect on file size.
If you prefer smaller file size, transcode the FLAC files to other lossless formats, such as Monkey's Audio or LA.

La really isn't a viable choice for anything other than off storage, man I wish they'd release the source or at least describe the compression algorithm it uses.

foobar2000 anyone? It doesn't delete the file afterwards, but it preserves all tags, and has any possebility of preserving the folder/file structure that you wish - You can use tags to recreate a whole new structure, or you can use the variables to reuse the original path.

What about WavPack?
The only codec I'm using at the moment...

Synthetic Soul's comparison indicates less than 0.3% improvement in compression (expressed as a difference). Maybe you'll see more improvement if you have a lot of mono recordings or something, but I have serious doubts about the figure that nightfishing has given (+/- 4%, meaning the size may actually get bigger when going from -6 to -8? ). If space is your concern, I'd probably go with TAK.

It was very unscientific, I re-encoded two tracks and saved an average of 4%.

Not enough to ever consider re-processing 10000 tracks (IMHO)

Oh I wasn't looking for flac alternative, I was just lamenting the fact that La's awesome algorithm goes to waste in it's abandoned form.

What version is being used? Is your considerable library encoded with an older version than the one you're currently using? This, too, will increase your compression gains when reencoding.

I'm surprised this hasn't already come up, but Synthetic Soul's FLAC conversion script can do batch reencodes from FLAC to FLAC, preserving all tags. It has the added benefit of checking to make sure that the conversion was successful before overwriting the old file.

http://www.synthetic-soul.co.uk/files/flac-113.txt

I've also written a VBScript version of Synthetic Soul's Batch files that offers similar functionality (Reflac, Decode to wav, Encode from wav, Test, or re-encode to MP3). it can be found here:

http://code.google.com/p/reflacer

Ongoing discussion is taking place in this topic:

http://www.hydrogenaudio.org/forums/index....showtopic=50993

-K

It doesn't hurt to do it. I used Synthetic Souls batch script to convert my FLAC library to the latest version of FLAC with -8 compression level.

Just start it overnight, mine took a while to do but it was worth it.