DSD-2-PCM -- proof of concept, test sample and source code here Options

[SebastianG]

The ZIP contains 4 files:
- dsd2pcm.jar (the converter written in Java, outputs raw 24/88 PCM, intel byte order)
- info.txt (contains some infos)
- test2822k.dsd (14 seconds, mono DSD, 5 megs)
- test44k.mp3 (conversion result)

have fun,
Sebi

Edit-2011: For the latest C/C++ source code see https://code.google.com/p/dsd2pcm/ It is released under the new BSD license. The attatchment to this post is still the first Java release.



This post has been edited by SebastianG: Dec 4 2011, 17:45

Attached File(s)

 dsd2pcm.zip ( 3.56MB ) Number of downloads: 2486

 

[SebastianG]

Just for kicks and giggles I rewrote most of "dsd2pcm" in C and C++. Compared to the java tool, it lacks the 2nd stage but it supports multiple channels and user-selectable bit ordering and output bitdepth (16 or 24). Without the 2nd stage you basically get "DXD" (PCM at 352.kHz). I figured, once you have a PCM stream you could just as well use any sampling rate converter to do further processing. Though, keep in mind that the resulting 24/352 PCM signal is a big waste of hard disc space since there will be a lot of ultrasonic noise in there (blame DSD, not me!). I recommend further downsampling and/or an additional lowpass filter (kicking in at 50 kHz). If you like such high sampling rates and want to do lossless compression afterwards, you really should do some filtering.

You might want to download some DSD files from here to test a little. I successfully tested a DSD64 stereo track like this:

CODE

sg@home:~/ccpp/dsd2pcm$ cat 2L38_01_DSD.dff | ./dsd2pcm 2 m 24 | sox -t raw -r 352800 -s -3 -c 2 - -r 88200 -b 24 test.wav

(Of course, this only works for uncompressed DSD files)

This conversion was done in approx 30 X real-time on my computer (2.4 GHz Core2 Duo). So, I'm a little surprized to see some people are having problems playing back DSD in real time. BTW: I didn't find the foobar2k DSD plugin. Does anybody have a link?

Cheers!
SG

latest source code: https://code.google.com/p/dsd2pcm/

This post has been edited by SebastianG: Dec 4 2011, 17:43

[vincefalks]

Just for kicks and giggles I rewrote most of "dsd2pcm" in C and C++. Compared to the java tool, it lacks the 2nd stage but it supports multiple channels and user-selectable bit ordering and output bitdepth (16 or 24). Without the 2nd stage you basically get "DXD" (PCM at 352.kHz). I figured, once you have a PCM stream you could just as well use any sampling rate converter to do further processing.

You might want to download some DSD files from here to test a little. I successfully tested a DSD64 stereo track like this:

CODE

sg@home:~/ccpp/dsd2pcm$ cat 2L38_01_DSD.dff | ./dsd2pcm 2 m 24 | sox -t raw -r 352800 -s -3 -c 2 - -r 88200 -b 24 test.wav

(Of course, this only works for uncompressed DSD files)

That's awesome, SG! I'm going to try a multichannel DFF...super . Oh no hang on - bah I'm a n00b - how do you compile it in windows, or can you provide a windows binary?

Honeslty not much info is known on this, but people keep claiming that 352.8kHz PCM IS DXD, when I really think it's not. I myself don't have tonnes of info on it, but for TRUE DXD I think you need to change something else in the encoding of it too (different roll-off filter to PCM). So it's just ultra hi-res PCM in this case.

This conversion was done in approx 30 X real-time on my computer (2.4 GHz Core2 Duo). So, I'm a little surprized to see some people are having problems playing back DSD in real time. BTW: I didn't find the foobar2k DSD plugin. Does anybody have a link?

Cheers!
SG

It's here.

It's DST-encoded files that we're having troubles with, not uncompressed DSD. The reference decoder is quite "unoptimal" by the looks of it, and could be improved a lot. Right now it's only good for storage, not on the fly decoding.

[SebastianG]

That's awesome, SG! I'm going to try a multichannel DFF...super . Oh no hang on - bah I'm a n00b - how do you compile it in windows, or can you provide a windows binary?

Sorry, I can only offer a "32bit x86 Linux binary" at the moment.

It's here.

Sweet.

Cheers,
SG

Attached File(s)

 dsd2pcm_32bit_x86_linux.zip ( 8.4K ) Number of downloads: 153
 dsd2pcm_32bit_x86_linux_static.zip ( 412.24K ) Number of downloads: 153