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[Mr ChriZ]

This is a bit of theoretical question...
If you take a bunch of APE Files.
Send them to burn to an MP3 disc.
Media Center will tell you the disc is overcapacity.
Could Media Center work out based on the target bitrate the likely
size of the MP3 Files, given the length in seconds of the APE Files with a margin for error for VBR?
This would be very useful determining how many tracks you could fit on the disc.
especially given my comp takes a good half an hour to create the disc
image to write such a CD, it's a bit of an imprecise science!

Additional Note:
Could the progress bar give some indication as to how many tracks have been
added to the disc image too?

Wahey!
1 Hour later and we have a CD!  This is why I don't burn them often!
Think I need a quicker computer for doing this on a regular basis.
Still waiting for a 10Ghz Quad Core processor tho (Which can be powered by
the sun and require no active cooling) :-)

[glynor]

All I can say is that most of my music is in lossy formats already (yeah, I know, I'm not audiophile-leet but my ears can't tell the difference between an APE and a high-bitrate VBR MP3), so I've not experienced that issue.

However, if the two things you describe are indeed true, that is terrible and pretty unworkable.  You definitely need a progress bar and proper calculations (at least good guestimates).

[Alex B]

This may help with space calculations:

MC cannot predict the encoded file sizes, but you could collect the files to a playlist first and use a constant bitrate when transcoding. Just monitor the total playback time and keep it below the disc limit.

Here is a table of the approximate maximum playback times for a 700 MB disc:

Code: [Select]

  Bitrate        Time
128 kbps   12 h 26 min
160 kbps    9 h 57 min
192 kbps    8 h 17 min
256 kbps    6 h 13 min
320 kbps    4 h 58 min
Leave some safe margin. Files are always a bit bigger than their theoretical size because of the tags.

For DVD discs you can multiply the times with a proper multiplier.

This can be used for speeding up things:

11.1.122 (02/15/06)

13. NEW: Added option to use super-fast Go-Go encoder to MP3 encoder. (2x-3x faster for doing on-the-fly conversion for handhelds, UPnP, etc.)

Thanks. It looks fine:



I suppose many users will like this option whenever time is short.

I tested the Go-Go speed with various settings @ 192 kbps:

Test PC: a 2.8 GHz P4
Test file: a disc image wave file, 477 MB, 47 min 20 s (Enigma - Voyageur).

Go-Go

-a -b 192 -m j    50 s     (abr 192, joint stereo)
-a -b 192 -m j -q 2    62 s    (abr 192, joint stereo, high quality)
-b 192 -m j -q 2    62 s    (cbr 192, joint stereo, high quality)
-b 192 -m j    53 s    (cbr 192, joint stereo)
-b 192 -q 2    68 s    (cbr 192, high quality)
-b 192    52 s    (cbr 192)

LAME (standard MC options)

VBR High, Fast    191 s
ABR 192    198 s
CBR 192    196 s

Go-Go is 3-4x faster. I think I'll use the "gogo.exe -a -b 192 -m j -q 2" custom command line for the CD-RW discs I burn for my car stereo. It should produce the highest quality at about 192 kbps. Though, I am going to try an ABX listening test soon.

I have now encoded a few albums with Go-Go using "gogo.exe -a -b 192 -m j -q 2". The results are very promising. I have compared the original ape files and the mp3 files. With high-end headphones I can occasionally hear some differences, but when I listen to the mp3 files separately I don't notice anything annoying. The mp3 files may be slightly different, but in general the audio quality is just fine. I think they are good enough for my car and portable MP3 CD players.

It would be nice if the iPod users could try this setting. Since it is ABR and has less bitrate fluctuation, it is possible that it fixes the high bitrate LAME VBR skipping problem.

On my P4 system it is over 3x faster than LAME VBR High Fast and because the encoding mode is ABR the resulting bitrate is more predictable too. The smallest file has been about 180 kbps and the biggest about 200 kbps so far. The average bitrate seems to be very near the 192 kbps target value.

Any target bitrate is possible so command line strings like "gogo.exe -a -b 165 -m j -q 2" and "gogo.exe -a -b 208 -m j -q 2" are fine.

[Mr ChriZ]

Cheers Alex.  I was using the Gogo encoder,
my computers just a little old in the tooth!