As far as I know (see URL) there is currently no MPEG2 hardware decoding support for the KM400A chipset, which includes the S3 UniChrome (VT8378) GPU. Although I guess there is some kind of obstacle to it, I had to ask for it anyway. I've written to VIA too, complaining about their announcements on colaborating with FOSS, saying that their driver was little better than VESA, and asking for some colaboration from them so I could actually watch DVDs on my computer.
Flaggins this as an enhancement.
KM400s don't have MPEG2 hardware decoding support, but only motion compensation acceleration. There would probably be very little gain from implementing support for it, but it might turn out as a side-effect if someone gets to implement mpeg4 acceleration.
I'm sorry, I though MPEG2 decoding and motion compensation were synonyms. Let me see if I understood what you've just said on MPEG4 acceleration: it's not supported by the VIA driver yet, but it should be because some chipsets can do it, so while implementing it it might be a good oportunity to go on and implement motion compensation with the KM400 chipset. Did I get it right?
(In reply to comment #3) > I'm sorry, I though MPEG2 decoding and motion compensation were synonyms. > VIA is using the terminology "acceleration" vs "decoding". The capabilities of the other unichromes are that they really can decode a suitably prepared mpeg stream. KM400 is not capable of that. The next step is doing IDCT acceleration. KM400 is not capable of that either according to the docs, although VIA claims it is. The final step of the decoding chain is motion compensation, and even if this was accelerated, the rest of the decoding would have to be done in software. > Let me see if I understood what you've just said on MPEG4 acceleration: it's not > supported by the VIA driver yet, but it should be because some chipsets can do > it, so while implementing it it might be a good oportunity to go on and > implement motion compensation with the KM400 chipset. Did I get it right? Yes. VIA's mpeg4 acceleration is (we believe) on the IDCT level, and motion compensation is programmed in a very similar fashion to the chip. VIA hasn't released any docs on mpeg4 accel, though. /Thomas
Sorry about the phenomenal bug spam, guys. Adding xorg-team@ to the QA contact so bugs don't get lost in future.
Leonardo Ferreira Fontenelle Do you still experience this issue with newer soft ? Please check the status of your issue.
(In reply to comment #6) > Leonardo Ferreira Fontenelle > Do you still experience this issue with newer soft ? > Please check the status of your issue. Thanks for your attention, but I don't own that computer anymore. It's been dead for some 4 years now. Feel free to close the bug report as fixed if you believe the feature should be working now.
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