I have few old (around 1.0) FLAC files, and I want to recode them to new FLAC - what should I do to not loose quality? Uncode them to WAV and then to new FLAC, or from old FLAC directly to new one?

Regardless of how you do it there should be no loss in quality. That's why they call it lossless!

You'll encode from lossless to lossless, hence go for the latter. Creating an intermediate .wav file wouldn't change anything besides the fact that you'd sacrifice all tags.

Just a small reminder: "Lossless" means mathematically lossless, not just audibly identical to the source, i.e. the decompressed data is bit-identical to the material it was created from.

Ad I can change compression level when I recompress without any negative effects? (I know, must read something albout FLAC and lossless, but currently no time for it.)

For a re-encode script, look at this post. Haven't tried with the latest version, though.

Exactly. The compression level only affects the processing speed. I for my part use the -6 value, since it's much faster than -7 and -8, while the additional gain in disk space is negligible in my opinion. A quick look into this table shows what I mean.

And FLAC frontend wouldn't be enough?

UPDATE:
OK, I got it now. Just downloaded official FLAC tools and gettin to work. Thank you for helping me!

Because I don't want to start a new topic for this problem, I hope someone can help me in this thread.

I want to re-encode my lossless files to FLAC. I have files in various formats like WAV, WV, FLAC, APE, ...

The main problem is that I have long folder names and many of them with Japanese letters. No batch file or encode program I have found so far could help me.

The optimal scenario would be a program (or batch) which scans all my folders and re-encode every single file to FLAC.

foobar?

If the path length is an issue you could try creating a virtual drive using SUBST.

dBpoweramp Music Converter R12 supports Unicode filenames and tags. It should be able to convert all popular lossless formats and it has a very nice GUI for the file selections and options.

Currently its official FLAC version is 1.2.0, but 1.2.1 is available as beta.

Edit: fixed the beta link

Doesn't work with the foobar "encode to same directory" function:


I just made random long folder names.


Thanks Alex, dBpoweramp's batch converter can encode music with the long file names and japanese letters.

Question:
dBpoweramp offers presets for (example) WV, but maybe I would like to use another switch like "-x". Is there a way to define the encoding settings manual?

Use the CLI encoder found in Codec Central. For wavpack, you'd use "-hx (or whatever switches you want to use) -i -y - [outfile]" Two things: 1) in the CLI encoder directory, you'll find a text file called encoder.txt. You have to edit this file to include the file extension you want. In this case, .wv. 2) You have to tell PowerAmp to pass the wave header and to add the tags. There should be checkboxes for that. Check them both, and you're good to go.

Ok, it worked, but the files are not bit identical when I encode with command line and dBpoweramp (wavpack 4.41.0). I use Hex Workshop to compare the files. It's always the same value which is replaced in the entire file (many times). How come? I guess the header is only a little bit different and it doesn't affect the sound quality. Even the size is identical.

The FLAC 1.2.1 command line for dBpoweramp is: -6 "[infile]" -f -o "[outfile]"
Files are only bit identical if you check "highest quality decoded source" and "pass wav header".

Lossless is lossless, if you install dBpoweramp Reference there is a utility codec called 'Calculate CRC', or you could use the built in wavpack or flac encoders and check the verify audio (which decodes the encoded audio and compares against the raw pre-encoded audio).