Re: [libdv-dev] XvImage support, YUV value range

[Erik W. <om...@cs...>]

On 30 Jul 2000, Charles 'Buck' Krasic wrote:

> Ah.  I tried this on my r128 box.  I see 120Mb write but only about 8M
> read.  Is this normal?

Yup.  Video cards are by design output-only devices.  That means all the
busses and such don't care about reads, so they're ignored, and thus very
slow.  This was one of Rasterman's primary points at his talk at LinuxTag.

         Erik Walthinsen <om...@cs...> - Staff Programmer @ OGI
        Quasar project - http://www.cse.ogi.edu/DISC/projects/quasar/
   Video4Linux Two drivers and stuff - http://www.cse.ogi.edu/~omega/v4l2/
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