AMD Geode SC3200 - Manual (Page 320)

320 AMD Geode™ SC3200 Processor Data Book
Video Processor Module 32581C
7.2.3 Mixer/Blender Block
The Mixer/Blender block of the Video Processor module
performs all the necessary functions to properly mix/blend
the video data and the graphics data. These functions
include Color Space Conversion (CSC), optional Gamma
correction, color/chroma key, and the mixing/blending logic.
See Figure 7-10 for block diagram of the Mixer/Blender
Block.
Video/Graphics mixing/blending must be performed in the
RGB format. The YUV to RGB CSC (Section 7.2.3.1 on
page 321) must be used on the video data if it is in YUV for-
mat. There is not a post mix/blend YUV to RGB CSC to
support the TFT output. If Gamma Correction (see Section
7.2.3.2) on the video data is desired, it must be done in the
color space of the input video data, which can be either
YUV or RGB. If Gamma Correction on the graphics data is
desired, it must be done in the color space of the input
graphics data, which is RGB.
The video data can be in progressive or interlaced format,
while the graphics data is always in the progressive format.
The Mixer/Blender can mix/blend either format of video
data with graphics data. F4BAR0+Memory Offset 4Ch[9]
programs the mix/blend format. Considering the color
space and the data format, the Mixer/Blender supports five
types of mixing/blending. Some of the mixing/blending
types have additional programming considerations to
enable them to work optimally. The valid mixing/blending
configurations are listed in see Table 7-1 on page 321
along with any additional programming requirements.
Figure 7-10. Mixer/Blender Block Diagram
01
10
Video, 4:4:4
Graphics,
CSC_FOR_
Optional
Gamma
Correction
RAM
CSC
YUV to
RGB
Color/Chroma
Key and
Mixer/Blender
CRT DACs and
TFT Interface
1/2 Y
Flicker
Filter
FLICKER_FILT_CNTRL = 01
0 1
/GV_GAMMA_SEL * /GAMMA_EN
GV_GAMMA_SEL * /GAMMA_EN
GV_GAMMA_SEL
CSC_FOR_VIDEO
0 1
01
CSC
RGB to
YUV
10
YUV or RGB
Cursor Color Key
01
COLOR_CHROMA_SEL
Color/Chroma Key
GRAPHICS
Compare
Compare
RGB
YUV Data
TVOUT Block