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opaqueice
2006-04-24, 05:38
I have some audio files in a non-standard 384 kbps mp3 format. Most audio players won't play that (an exception is freeamp), but slimserver will - most of the time. According to the slimserver FAQ, it only handles up tp 320 kbs mp3s, so this isn't an officially supported format. There are a couple of issues, however:

slimserver incorrectly displays the bit rate - it shows something more or less random when it plays these files.

more seriously, occasionally it won't play one at all (while freeamp will). Unfortunately I don't know what it is that determines when slimserver won't play these files - it's happened in I think 2 out of about 30 files so far.

Any suggestions? Is this likely to be something that's supported in future releases?

T
2006-04-24, 05:53
384 is only for Layer 2, not layer 3. Are you sure that they are Layer 3
encoding?

Tom

opaqueice
2006-04-24, 06:14
384 is only for Layer 2, not layer 3. Are you sure that they are Layer 3
encoding?

Tom

Yes - they are mp3. Apparently the LAME encoder allows arbitrary bitrate with the free format switch enabled, and that's how these were encoded.

Ben Sandee
2006-04-24, 07:13
On 4/24/06, opaqueice <
opaqueice.26rsiz1145884502 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
>
> Yes - they are mp3. Apparently the LAME encoder allows arbitrary
> bitrate with the free format switch enabled, and that's how these were
> encoded.


You might consider converting the files to FLAC. You won't lose any quality
and it will be more reliably supported.

Ben

opaqueice
2006-04-24, 07:46
You might consider converting the files to FLAC. You won't lose any quality
and it will be more reliably supported.
Ben

Great suggestions - thanks! That hadn't occurred to me. It's certain there's no quality loss in that conversion?

Mark Lanctot
2006-04-24, 07:57
Great suggestions - thanks! That hadn't occurred to me. It's certain there's no quality loss in that conversion?

FLAC is lossless - you won't lose anything in the conversion (not counting what you already lost in the original conversion to MP3 though).

But if you were to convert from one lossy format to another, for example to 192 kbps MP3, you'd lose more data.

EAC can decompress MP3 to WAV and then encode in FLAC, but you may lose tag data. I'm sure there's a program out there that can decompress to WAV and re-encode in FLAC in one step, preserving the tag data.

Ben Sandee
2006-04-24, 08:00
On 4/24/06, opaqueice <
opaqueice.26rwxc1145890202 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
>
> Ben Sandee Wrote:
> >
> > You might consider converting the files to FLAC. You won't lose any
> > quality
> > and it will be more reliably supported.
> > Ben
>
> Great suggestions - thanks! That hadn't occurred to me. It's certain
> there's no quality loss in that conversion?


If you do it right, yes it's certain. You can hold onto the original files
until you've convinced yourself, but you've already done the only lossy
encoding that would be done to your music by encoding to MP3 in the first
place. MP3->WAV->FLAC is lossless. FLAC of course is quite a bit larger in
size, but your 380+kbps mp3's aren't exactly tiny anyway so I doubt that
matters to you.

For conversion, check out foobar2000 -- I think it would make the process
pretty straightforward for you. Assuming it can read your 'special' files
that is. :-)

Ben

opaqueice
2006-04-24, 09:58
OK, great - thanks!

Unfortunately foobar can't understand these files (unless there's a plugin I couldn't find) but there must be something which can.

Ken
2006-04-24, 10:04
Try dBpowerAMP. Unfortunately there is a small charge for using the MP3 codec, but it will do what you want, with the suitable flac plug in which is available from dBpowerAMP.

Ken

T
2006-04-24, 11:08
> Unfortunately foobar can't understand these files (unless there's a
> plugin I couldn't find) but there must be something which can.

Doubtful, as there is no way to tell an mp3 stream that it is 384 kbps. The
header has no way to encode that bit-rate.

Tom

JimB
2006-04-24, 11:44
On 4/24/06, opaqueice <
opaqueice.26rsiz1145884502 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
>
> Yes - they are mp3. Apparently the LAME encoder allows arbitrary
> bitrate with the free format switch enabled, and that's how these were
> encoded.


You might consider converting the files to FLAC. You won't lose any quality
and it will be more reliably supported.

Ben



Does anyone know if you can reliably convert high quality, non-DRM VBR WMA encoded files to FLAC?

Ben Sandee
2006-04-24, 12:04
On 4/24/06, opaqueice <
opaqueice.26s2xz1145898001 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
>
> OK, great - thanks!
>
> Unfortunately foobar can't understand these files (unless there's a
> plugin I couldn't find) but there must be something which can.


If you used lame to generate the files, surely it can decode them?

lame --decode <input.mp3> <output.wav>

?

Ben

opaqueice
2006-04-24, 13:03
>
Doubtful, as there is no way to tell an mp3 stream that it is 384 kbps. The
header has no way to encode that bit-rate.
Tom

Well, freeamp knows what bitrate they're at. Although I noticed it sometimes says 383 rather than 384, so possibly it's somehow analyzing the file, rather than using header info?



If you used lame to generate the files, surely it can decode them?


I didn't encode them (I purchased them like that). I'm sure you're right, I just haven't had a chance to try it yet. I'll report back later.

opaqueice
2006-04-24, 13:45
If you used lame to generate the files, surely it can decode them?

lame --decode <input.mp3> <output.wav>
Ben

That does work, and furthermore the mp3 files which (for some reason) slimserver won't play work fine once converted to wavs. LAME correctly identifies the files as free format 384 kbps.

Thanks again!

EDIT: ministream ripper will convert mp3 -> flac in one step (including these 384s), and has a batch convert option (although it's crippleware).

MrStan
2006-04-25, 00:52
Does anyone know if you can reliably convert high quality, non-DRM VBR WMA encoded files to FLAC?

You can use MPlayer to decode to wave and save to disc and then convert to flac from there. (I think it should be OK with VBR WMA)

opaqueice
2006-06-20, 01:41
Just an update on this in case anyone else cares - mediacoder, a free transcoder, has kindly added support for the LAME codec, so it can now transcode batches of files from 384 kbps mp3 to FLAC (or many other formats). You can get it here:

http://mediacoder.sourceforge.net/