Why can't my standalone players play wmv2 (wmv8) ?

[Music Fan]

Hi,
I have a Pioneer dvd player and a Sony BD player, and they both can play wmv1 (wmv7) and wmv3 (wmv9) but not wmv2 (wmv8).
Does anybody know what could be the explanation ?
I guess that this codec has something specific which avoid its reading by (some) standalone players.
I don't find anything here ;
http://en.wikipedia.org/wiki/Windows_Media_Video#Versions

[Reimar]

Hi,
I have a Pioneer dvd player and a Sony BD player, and they both can play wmv1 (wmv7) and wmv3 (wmv9) but not wmv2 (wmv8).
Does anybody know what could be the explanation ?

I certainly do not _know_, however I can guess: WMV3 is (basically) VC-1, which is part of BD, so they will have a hardware decoder for it, and WMV1 probably is simple enough that they can decode it in software. And WMV2 could be the problematic case: Not being able to (consistently?) decode in software, too irrelevant to have hardware decoders available, thus not worth trying to support it.

[Music Fan]

My dvd player cannot play VC1 and it plays wmv1 and wmv3.

[Ghitulescu]

Why keen on using formats that are not supported by any HW (thus less portable), are patent protected (thus less "maleable") when the choice for other codecs/formats/containers is so rich? There are also extremely few sources for native WMVs...

[Music Fan]

I don't encode in wmv2 of course, I just wanna understand what happens with wmv2 in my players (by curiosity). I guess there's an explanation.

[Ghitulescu]

I can only say it's a licencing issue. Which may not reside on Sony/Pioneer side only, but also on the chip manufacturers' one (probably MediaTek). What for you looks like 1-cent issue, for chip- and player- manufacturers may become a 200'000€ issue .... volume licencing (patents, copyrights and design models), developers' costs ...

[Reimar]

My dvd player cannot play VC1 and it plays wmv1 and wmv3.

So it can't play e.g. http://samples.mplayerhq.hu/V-codecs/WVC1/Test_1440x576_WVC1_6Mbps.wmv ?
I would suspect that it can play that one, and in that case it can play VC-1, though it possibly can handle neither ES nor TS container formats.

[Music Fan]

My dvd player can't play higher than 720.576 resolutions (and I believe that this 6Mbps bitrate is also too high).
But I made a test with a wvc1 file in a lower resolution than 720.576 on my Pioneer dv-610 and it worked ! Not useful for me because my Sony BD player play wvc1 in HD but it's interesting to know.
Anyway, it has nothing to do with wmv2.