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Gear / Technical Help => Post-Processing, Computer / Streaming / Internet Devices & Related Activity => Topic started by: taper420 on February 26, 2008, 11:08:21 AM

Title: Lossless Surround Sound?
Post by: taper420 on February 26, 2008, 11:08:21 AM
As far as I can tell the only way to author a surround sound DVD is with a lossy codec.

Is there some way to make a surround mix with full lossless 24 bit files? On a standard DVD-V.

And if so what kind of software should I be looking for.... on a mac? Right now I have the latest FCP studio, but can't find a way to do it.
Title: Re: Lossless Surround Sound?
Post by: Petrus on February 26, 2008, 02:55:42 PM
With lossless 5.1 24bit surround sound you could fit only one hour of sound on the disk and no video...

uncompressed 16/44 PMC is about 600 MB/h, 24/48 about 1 GB/h. DVD capacity is 4.7 GB. Simple math.
Title: Re: Lossless Surround Sound?
Post by: newscane on February 26, 2008, 09:01:37 PM
As far as I can tell the only way to author a surround sound DVD is with a lossy codec.

Is there some way to make a surround mix with full lossless 24 bit files? On a standard DVD-V.

And if so what kind of software should I be looking for.... on a mac? Right now I have the latest FCP studio, but can't find a way to do it.
Surcode may do the trick, but I think they have a Mac version for only one of their products...

http://www.surcode.com/
Title: Re: Lossless Surround Sound?
Post by: taper420 on February 27, 2008, 08:07:21 AM
As far as I can tell the only way to author a surround sound DVD is with a lossy codec.

Is there some way to make a surround mix with full lossless 24 bit files? On a standard DVD-V.

And if so what kind of software should I be looking for.... on a mac? Right now I have the latest FCP studio, but can't find a way to do it.
Surcode may do the trick, but I think they have a Mac version for only one of their products...

http://www.surcode.com/

Thanks... it seems that the MLP lossless encoder they have may only be applicable to DVD-A's. And it's $2500.

So technically possible but not economically feesable for a hobbiest.
Title: Re: Lossless Surround Sound?
Post by: alpine85 on February 27, 2008, 02:08:06 PM
there's an open source program - can't remember what it's called - I downloaded it a while back (on my laptop - that's why I can't look it up) but haven't had time to figure it out.  Seems like it's command-line only (no GUI).  If you go to sourceforge.net and search for "dvd audio" you'll probably find it.
Title: Re: Lossless Surround Sound?
Post by: Petrus on February 28, 2008, 04:22:23 PM
There is no way you can fit lossless 5.1 on a standard DVD, the maximum allowed data rate can not accomodate it. At least if you want to have any decent video to go with the audio.
Title: Re: Lossless Surround Sound?
Post by: Will_S on March 02, 2008, 07:02:29 PM
There is no way you can fit lossless 5.1 on a standard DVD, the maximum allowed data rate can not accomodate it. At least if you want to have any decent video to go with the audio.

I don't necessarily follow or agree with your math, with the right encoders.

Earlier you quoted ~600MB/hr for 16/44.1 PCM.  Of course that's stereo, and completely uncompressed.  So going from 2 tracks to 6 tracks, you are now at ~1800MB/hr.  But FLAC or other LOSSLESS compression algorithms can usually get a file down to about 60% of its original size.  The center channel should be highly correlated with left and right, so you'd probably get better compression there.  By definition there's a very limited frequency range to worry about in the .1 channel, so that should compress very well as well.   So maybe 1GB/hr of lossless 5.1 channel 16/44, if not better.  So you could make a two hour disc with over half the storage space devoted to video.
Title: Re: Lossless Surround Sound?
Post by: Petrus on March 03, 2008, 03:10:35 AM
How about the maximum data rate specified in the DVD standard?
Title: Re: Lossless Surround Sound?
Post by: Will_S on March 03, 2008, 09:39:03 AM
How about the maximum data rate specified in the DVD standard?

How about it?

1GB/hr audio ~= 1,000 MB/hr = 16.7 MB/min = .277 MB/sec
1x DVD data rate = 1.32 MB/sec.
Title: Re: Lossless Surround Sound?
Post by: Petrus on March 03, 2008, 10:28:53 AM
live and learn...
Title: Re: Lossless Surround Sound?
Post by: pike1957 on March 19, 2008, 07:55:49 PM
I tried doing this a while ago.  Used Audacity to output the six channels of 5.1 audio to Flac files, then burned to a DVD video disc using LPLEX.  The DVD video disk standard does support this (at 48khz and up to 24bit).  Next step was to find a player.  This is not supported over S/PDIF, and I could find no player with the necessary 6 d/a converters.  I suspect a DVD audio player with analog outputs could handle this, but have not tried.  I tried contacting tech support for various manufacturers to try and find one that made a player that supported this DVD video standard, but they either didn't reply, or if they did reply, the reply was worthless.  I resorted to DTS encoding in the end.