On Sat, Nov 06, 1999 at 07:59:44PM +0100, Marcus Sundberg wrote:
> Jan Kneschke <[EMAIL PROTECTED]> writes:
>
> > currently i try to find a way to set up a YUV-crossblit in ggi. GGI has no
> > support for it yet. neither a GT_YUV422 nor a abstract and fitting
> > pixel-model.
> > ggi_pixel_format only supports buffers that can be accessed by a shift-mask.
> > YUV422 is a common color-format most often used by tv-cards, mpeg-movies and
> > the like. two pixels are represented by 4 bytes:
> >
> > Y1U1Y2V1Y3U2Y4V2....
> > | | | |
> >
> > Y1, U1 and V1 is the first pixel.
> > Y2, U1 and V1 is the second pixel.
> > and so on.
> >
> > ok. this one can be implented in ggi. i don't know, but i'm sure it can be
> > done. the next one is trickier.
> >
> > YUV411:
> >
> > Y1U1Y2U2.......
> > YaV1YbV2......
> >
> > U and V are transmitted in two lines. GGI can't handle this.
> >
> > but hey, as far as i know accelerated color-space conversion is most often
> > done YUV422(packed) -> RGB, so lets try to get this one defined.
> >
> > one solution could be the conversion from YUV422(packed) to YUV422(planar)
> > were you seperate the components into 3 buffers (Y1Y2Y3Y4)(V1V2)(U1U2) like
> > those bit-plane modes. but this wont give us the directbuffer a currently
> > need for ggitv.
> >
> > all i want is a visual i can crossblit to another visual. the source would
> > be YUV422 and the destination a KGI(con)-visual that converts YUV422->RGB in
> > hardware.
> >
> > has someone a idea how intergrate it in ggi ??
>
> The answer is simple: forget everything about crossblit and YUV-visuals.
>
> Visuals are heavy-weight objects, and should never be used for
> images, pixmaps or video-streams.
>
> Things like this belong in the yet-to-be-written LibGBLIT extension.
> It will handle blitting images in all kinds of formats, including
> YUV and other colorspaces, with hardware acceleration if available,
> from both main-memory (via AGP or DMA when available) and on-board
> memory.
>
> You are welcome to come up with an initial framework for this
> extension. Just remember to keep it simple, but flexible, in the
> beginning. Then we'll expand it as necessary later.
shall set up a framework or not ?? (andy, marcus)
what should be included ??
> //Marcus
> --
> -------------------------------+------------------------------------
> Marcus Sundberg | http://www.stacken.kth.se/~mackan
> Royal Institute of Technology | Phone: +46 707 295404
> Stockholm, Sweden | E-Mail: [EMAIL PROTECTED]
thats all
Jan
---
-)= Jan Kneschke -- Kiel -- Germany -- http://www.kneschke.de =(-
