mirror of https://github.com/mpv-player/mpv
41 lines
1.3 KiB
Plaintext
41 lines
1.3 KiB
Plaintext
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mga_vid - MGA G200/G400 YUV Overlay kernel module
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Author:
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Aaron Holtzman <aholtzma@ess.engr.uvic.ca>, Oct 1999
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Contributions by:
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Fredrik Vraalsen <vraalsen@cs.uiuc.edu>
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Alan Cox <alan@lxorguk.ukuu.org.uk>
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WARNING ----- WARNING
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This code messes with your video card and your xserver. It will probably
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lock up your box, format your hard drive, and cause your brand new g400
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MAX to spout 6 inch flames. You have been warned.
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WARNING ----- WARNING
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What does this code do?
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mga_vid is a kernel module that utilitizes the Matrox g200/g400 video
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scaler/overlay unit to perform YUV->RGB colorspace conversion and
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arbitrary video scaling.
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mga_vid is also a monster hack.
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How does mga_vid work?
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This kernel module sets up the BES (backend scaler) with approriate values
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based on parameters supplied via ioctl. It also maps a chunk of video
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memory into userspace via mmap. This memory is stolen from X (which may
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decide to write to it later). The application can then write image data
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directly to the frame buffer (if it knows the right padding, etc).
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How do I know if mga_vid works on my system?
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There are test applications called mga_vid_test_g400 and mga_vid_test_g200.
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Use the appropriate one for your card. This test code should draw some
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nice 256x256 images for you if all is working well.
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