Samsung S5PC100, User Manual

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VIDEO PROCESSOR S5PC100 USER’S MANUAL (REV1.0)
9.8-38
LINE_SLOPE [7:0]
Slope, unsigned 1.7 format. (because of 1bit
integer, LINE_SLOPE has range from 0 to
1.9921875.)
* Note : (1.7) format means that
- ‘1’ is a integer
- ‘7’ is a fraction. (Located in LSB)
Example) LINE_SLOPE = 0.5 = 1*2^(-1)
Because of 7bit fraction, it is had to do 7 time left
shift operation. As a result, register value is 1/2 *
2^7 = 0x40
0
NOTE :
8 equation is related with Figure 9,8-7. Input luminance value between 0 ~ 255 is divide by 8 steps. Each of them is matched
with each of 8 equations. So, we can make the new curve of the contrast and luminance as using 8 equation’s combination.
Each equation is matched like following as :
- PP_LINE_EQ0 : 0 ~ 31
- PP_LINE_EQ1 : 31 ~ 63
- PP_LINE_EQ2 : 64 ~ 95
- PP_LINE_EQ4 : 96 ~ 127
- PP_LINE_EQ5 : 128 ~ 159
- PP_LINE_EQ6 : 160 ~ 191
- PP_LINE_EQ7 : 192 ~ 223
- PP_LINE_EQ8 : 224 ~ 255
4.3.76 Video Processor Brightness Offset Control Register for Y (PP_BRIGHT_OFFSET, R/W, Address =
0xF010_ 0238)
PP_BRIGHT_OFFSET Bit Description Reset Value
Reserved [31:9] Reserved, read as zero, do not modify 0
PP_BRIGHT_OFFSET [8:0]
Offset for Y brightness control (Signed 1.8 format)
Bright enhanced Y = Org Y + BRIGHT_OFFSET
0xFF : +255
…
0x1 : + 1
0x0 : 0
0x1FF : – 1
…
0x100 : - 256
0
NOTE : Figure 9.8- shows examples of how VP controls brightness and contrast of image sequence using PP_LINE_EQ0 ~
PP_LINE_EQ7 registers and PP_BRIGHT_OFFSET register. Input to output luminance mapping curve is
approximated by 8 sub-lines described by PP_LINE_EQ0 ~ PP_LINE_EQ7. Consequently, brightness and contrast is
controlled in very flexible way.