Rainbow Electronics AT91CAP9S250A - Manual (Page 917)

917
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
Figure 45-5. Resize Examples
45.3.4.2 Color Space Conversion
This module converts YCrCb or YUV pixels to RGB color space. Clipping is performed to ensure
that the samples value do not exceed the allowable range. The conversion matrix is defined
below and is fully programmable:
Example of programmable value to convert YCrCb to RGB:
An example of programmable value to convert from YUV to RGB:
1280
1024
480
640
32/16 decimation
1280
1024 288
352
56/16 decimation
R
G
B
C
0
0 C
1
C
0
C
2
– C
3
–
C
0
C
4
0
Y Y
off
–
C
b
C
boff
–
C
r
C
roff
–
×
=
R 1.164 Y 16 –
( ) ⋅
1.596 C
r
128 –
( ) ⋅
+ =
G 1.164 Y 16 –
( )
0.813 C
r
128 –
( ) ⋅
– 0.392 C
b
128 –
( ) ⋅
–
⋅
=
B 1.164 Y 16 –
( ) ⋅
2.107 C
b
128 –
( ) ⋅
+ = ⎩
⎪
⎨
⎪
⎧
R Y 1.596 V
⋅
+ =
G Y 0.394 U
⋅
– 0.436 V
⋅
– =
B Y 2.032 U
⋅
+ = ⎩
⎪
⎨
⎪
⎧