RIVA128ZX Datasheet, PDF (42/85 Pages) STMicroelectronics – 128-BIT 3D MULTIMEDIA ACCELERATOR

RIVA128ZX
128-BIT 3D MULTIMEDIA ACCELERATOR
7 VIDEO PLAYBACK ARCHITECTURE
The RIVA128ZX video playback architecture is
designed to allow playback of CCIR PAL or NTSC
video formats with the highest quality while requir-
ing the smallest video surface. The implementa-
tion is optimized around the Windows 95 Direct
Video and ActiveX APIs, and supports the follow-
ing features:
• Accepts interlaced video fields:
- This allows the off-screen video surface to
consume less memory since only one field
(half of each frame) is stored. Double buffer-
ing between fields is done in hardware with
Figure 43. Video scaler pipeline
‘temporal averaging’ being applied based on
intraframing.
• Linestore:
- To support high quality video playback the
RIVA128ZX memory controller and video
overlay engine supports horizontal and verti-
cal interpolation using a 3x2 multitap interpo-
lating filter with image sharpening.
• YUV to RGB conversion:
- YUV 4:2:2 format to 24-bit RGB true-color
- Chrominance optimization/user control
• Color key video composition
Linestore
YUV
Vertical
Interpolation
Filter
(Smooth/Sharpen)
Color Space
Conversion to 24-bit
RGB
Horizontal
Interpolation
24-bit RGB
Video output
Video windowing, merge
with graphics pixel pipeline
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