Datasheet

SAM9G20
DS60001516A-page 700  2017 Microchip Technology Inc.
38.3.5 Codec Path
38.3.5.1 Color Space Conversion
Depending on user selection, this module can be bypassed so that input YCrCb stream is directly connected to the format converter mod-
ule. If the RGB input stream is selected, this module converts RGB to YCrCb color space with the formulas given below:
An example of coefficients is given below:
38.3.5.2 Memory Interface
Dedicated FIFO are used to support packed memory mapping. YCrCb pixel components are sent in a single 32-bit word in a contiguous
space (packed). Data is stored in the order of natural scan lines. Planar mode is not supported.
38.3.5.3 DMA Features
Unlike preview datapath, codec datapath DMA mode does not support linked list operation. Only the CODEC_DMA_ADDR register is used
to configure the frame buffer base address.
Y
C
r
C
b
C
0
C
1
C
2
C
3
C–
4
C–
5
C–
6
C–
7
C
8
R
G
B
×
Y
off
Cr
off
Cb
off
+=
Y 0.257 R⋅ 0.504 G 0.098 B 16+⋅+⋅+=
C
r
0.439 R⋅ 0.368 G⋅– 0.071 B 128+⋅–=
C
b
0.148 R⋅– 0.291 G 0.439 B 128+⋅+⋅–=




