[Matroska-devel] Re: [mpc-devel] SV7 to SV 8 conversion for matroska integration : call for opinions

Joël Bourquard numlock at freesurf.ch
Mon Nov 17 00:02:21 CET 2003

On Sun, 2003-11-16 at 23:30, Christian HJ Wiesner wrote:
> Hi,
> please use the 'reply all' button of your mail client when replying, so 
> all lists get copied.
> Frank convinced us that using SV7 in matroska is maybe not a good idea. 
> Therefore the matroska team was discussing a couple of options today 
> about MPC integration into matroska :

> 2. Make an encoder filter for DirectShow or a little CLI app with 
> libmatroska based on Frank's 'alpha' SV8 encoder, which seems to be 
> quite usable and according to Frank was tuned to overcome some reported 
> sound limitations in the existing SV7 encoder. We could tag the current, 
> 'alpha SV8 bitstream' as SV 7.2 , SV 7.5 or even SV8, and write the 
> blocks directly into matroska files, stripping even the block size from 
> the SV8 alpha bitstream to become as independant as possible from future 
> bitstream changes. The chances are good that these files would be 100% 
> SV8 compatible. If not, we could tag them differently, or convince Frank 
> to make SV9 instead of SV8 ;-) ....

Ah, I didn't know the pre-SV8 streams were *that* close to a final
stage. That's good news !

However, please consider the following:
- do these pre-SV8 streams support multichannel audio ?
- can SV7 streams easily be ported to pre-SV8 ?

Then, if pre-SV8 supports the above two points:
- why not extending/generalizing it to also support MDCT-domain audio ?
Hopefully this would only require a few additional bits ;-)


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