
ú
ú
ú
û
ù
ê
ê
ê
ë
é
+
ú
ú
ú
û
ù
ê
ê
ê
ë
é
ú
ú
ú
û
ù
ê
ê
ê
ë
é
=
ú
ú
ú
û
ù
ê
ê
ê
ë
é
0
0
0
1
0
0
0
1
0
0
0
1
in
in
in
out
out
out
B
G
R
B
G
R
camisp-E161
0
256
_
_
_
=
=
=
=
others
BB
MTX
GG
MTX
RR
MTX
camisp-E162
ú
ú
ú
û
ù
ê
ê
ê
ë
é
+
ú
ú
ú
û
ù
ê
ê
ê
ë
é
ú
ú
ú
û
ù
ê
ê
ê
ë
é
=
ú
ú
ú
û
ù
ê
ê
ê
ë
é
OFSTCR
OFSTCB
YOFST
B
G
R
CSCBCR
CSCGCR
CSCRCR
CSCBCB
CSCGCB
CSCRCB
CSCBY
CSCGY
CSCRY
Cr
Cb
Y
in
in
in
camisp-E095
Public Version
www.ti.com
Camera ISP Functional Description
That leads to:
6.4.7.1.13 Camera ISP VPBE Preview Gamma Correction
Gamma correction is performed on each of the R, G, and B pixels separately by indexing programmable
gamma look-up tables. Each table has 1024 8-bit entries. The input data value is used to index into the
table and the table content is the output.
The gamma table can be bypassed (
[26] GAMMA_BYPASS). In this case, the output of the
gamma correction is the 8 MSB of the 10-bit input. The gamma table can be written only while the preview
engine is disabled.
6.4.7.1.14 Camera ISP VPBE Preview RGB to YCbCr Conversion, Luminance Enhancement,
Chrominance Suppression, Contrast and Brightness, and 4:2:2 Downsampling and Output
Clipping
6.4.7.1.14.1 RGB-to-YCbCr Conversion
The RGB-to-YCbCr conversion module has a 3x3 square matrix and converts the RGB color space of the
image data into the YCbCr color space. In this module, the following calculation is performed using the
contents of the
,
, and
registers:
Gains are in S10Q8 format, and offsets are in S8Q0 format for chroma and U10Q0 for luma.
NOTE:
Program the following values after reset for correct color conversion:
•
[19:10] CSCGCR = 0x39E
•
[9:0] CSCRCR = 0x080
6.4.7.1.14.2 Nonlinear Luminance Enhancement
Nonlinear luminance enhancement functions as an edge enhancer (crossed in the horizontal direction). It
can be enabled or disabled using the
[15] YNENHEN parameter. If it is enabled, a look-up
table with 127 20-bit entries must be programmed. Each entry contains a 10-bit signed offset value in the
MSBs, and a 10-bit signed slope in the LSBs.
NOTE:
Some details of this feature are not available in the public domain.
1211
SWPU177N – December 2009 – Revised November 2010
Camera Image Signal Processor
Copyright © 2009–2010, Texas Instruments Incorporated