Camera Isp Csi1/Ccp2 Yuv422 Big Endian - Texas Instruments OMAP36 Series Technical Reference Manual

Camera ISP Environment
6.2.4.4.1 Camera ISP CSI1/CCP2 Pixel Data Format
This section summarizes how the CSI1/CCP2B pixel data formats are transmitted over the serial interface
and how the pixels are reconstructed, stored in memory, or passed to the video port.
The CSI1/CCP2B receiver can cope with all data formats if the data line length sent through the
associated PHY is a multiple of 32 bits. This condition is required for the CSI1/CCP2B receiver to work
correctly.
However, some data formats impose stronger line-length constraints to correctly finish pixel reconstruction
at the end of the lines. If the additional constraints are not respected:
• Only the last reconstructed pixels in every line are erroneous. The missing bits are replaced with 0s to
perform pixel reconstruction.
• The FW_IRQ interrupt is triggered.
6.2.4.4.1.1 Camera ISP CSI1/CCP2 YUV Pixel Data Formats
The YUV422 data format can be stored to memory in little- or big-endian format. The line length sent
through the associated PHY must be a multiple of 32 bits.
YUV422 data format can also be sent to the video port.
YUV422 + VP is used to output RAW8 data to the video port: YUV422 + VP is equivalent to RAW8 + VP.
Figure 6-8 and Figure 6-9
YUV422 big endian
Transmitter
u
1
u0 u1 u2 u3 u4 u5 u6 u7 y0 y1 y2 y3 y4 y5 y6 y7 v0 v1 v2 v3 v4 v5 v6 v7 y0 y1 y2 y3 y4 y5 y6 y7
First transmitted bit
Receiver
u
1
u7 u6 u5 u4 u3 u2 u1 u0 y7 y6 y5 y4 y3 y2 y1 y0 v7 v6 v5 v4 v3 v2 v1 v0 y7 y6 y5 y4 y3 y2 y1 y0
31
Picture width = n
u y
v
1
1 1
u
y v
n+1 n+1
n+1
...
t0: VP_DATA[7:0] = [u7 u6 u5 u4 u3 u2 u1 u0]
t1: VP_DATA[7:0] = [y7 y6 y5 y4 y3 y2 y1 y0]
t2: VP_DATA[7:0] = [v7 v6 v5 v4 v3 v2 v1 v0]
t3: VP_DATA[7:0] = [y7 y6 y5 y4 y3 y2 y1 y0]
1102
Camera Image Signal Processor
Public Version
show big-endian and little-endian YUV422 format, respectively.
Figure 6-8. Camera ISP CSI1/CCP2 YUV422 Big Endian
y
1
y
1
y u y
...
Odd lines
2 3 3
y
y u
...
Even lines
n+3 n+3
n+2
Copyright © 2009–2010, Texas Instruments Incorporated
v
1
v
1
First two pixels of first odd line are: {y ,v ,u } and {y ,v ,u }
First two pixels of first even line are: {y
SWPU177N – December 2009 – Revised November 2010
www.ti.com
y
2
time
y
2
FIFO
Data mem org
0
1 1 1 2 1 1
,v ,u } and {y ,v ,u }
n+1 n+1 n+1 n+2 n+1 n+1
YUV4:2:2 + VP
camisp-181