MPEG Decoder Requirements
[This is preliminary documentation and subject to change.]
The video card for the MPEG decoder must have the following features:
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Super Video Graphics Array (SVGA) card capable of at least 800 x 600 x 8 bits per pixel, with a 60 hertz refresh rate.
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Support for high-speed, two-dimensional graphics acceleration, preferably with support for three-dimensional bitmaps and MPEG textured polygons.
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MPEG-2 decoder chip set, capable of a speed of 15 megabits per second and a screen resolution of 720 x 480 x YUV 4:2:2.
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Data transfer using bus mastering from memory to the MPEG decoder, at up to 2 megabytes per second in speed. Such transfer must include support for unaligned, odd byte transfer and scatter/gather memory access.
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Capture and display of each 720 x 240 video field stretched vertically to 720 x 80 without decimation.
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Broadcast cable television tuner that supports NTSC or PAL signals.
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Composite super VHS (SVHS) – type chip that decodes NTSC or PAL to YUV, with an interface to the SVGA chip set.
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Composite SVHS-type chip that encodes data to NTSC or PAL, with a direct interface from the MPEG decoder.
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Audio and video crossbar switching chips for interconnecting composite and SVHS inputs and outputs.
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SVGA format that supports capture of YUV frame buffers for prioritized overlay and scaling with horizontal and vertical interpolation.
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Merging of YUV video frames and SVGA video frames in the digital to analog converter (DAC) using chroma and color keying.
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Controllable Macrovision video encoding of all composite video signals that are output.
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Decoding of vertical blanking interval (VBI) data for NTSC format, including decoding of such information as closed captioning, from all composite inputs.
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Encoding of NTSC VBI data (such as closed captioning or time codes) on all composite outputs.
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Full driver support for the Microsoft® Windows® 98 operating system, including display driver and MPEG minidriver support.
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Support for the output of audio from video sources to the line input of standard audio cards.