Samsung S3C2451X User Manual page 425

S3C2451X RISC MICROPROCESSOR
Off-Screen Rendering
Off-screen bit block transfer copies pixel data from off-screen memory to frame buffer. Color space conversion is
performed automatically if SRC_COLOR_MODE differs from DEST_COLOR_MODE. YUV 4:2:2 input is also
supported.
Transparent Mode
2D can render image in Transparent Mode. In this mode, the pixels having the same color with background color
(BG_COLOR) are discarded, resulting in a transparent effect. The function of Transparent Mode is illustrated in
the images below, in which the BG_COLOR is set to white.
2D also support Blue Screen Mode, in which the pixels having the same color with background color
(BG_COLOR) are replaced by the blue screen color (BS_COLOR).
2D supports both host-to-screen mode and memory-to-screen mode of BLT.
Related Registers
COORD_0
COORD_1
COORD_2
COORD_3
X-INCR
Y-INCR
SRC_BASE_ADDR
Figure 19-5 Transparent Mode
Coordinate of the leftmost topmost coordinate of the source image
Coordinate of the rightmost bottommost coordinate of the source image
Coordinate of the leftmost topmost coordinate of the destination image
Coordinate of the rightmost bottommost coordinate of the destination image
X increment value of the source image coordinates. If it is greater than 1, the image
is shrunk horizontally; smaller than 1, stretched. This value is ignored when S bit in
CMDR_1 is disabled or host-to-screen mode is used.
X-INCR = (COORD1_X – COORD0_X) / (COORD3_X – COORD2_X)
Y increment value of the source image coordinates. If it is greater than 1, the image
is shrunk vertically; smaller than 1, stretched. This value is ignored when S bit in
CMDR_1 is disabled or host-to-screen mode is used.
Y_INCR = (COORD1_Y – COORD0_Y) / ( COORD3_Y – COORD2_Y)
The base address of the source image (when memory-to-screen mode is used).
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
2D
19-5