camisp-106
CCDC_CLAMP [24:10] OBST
CCDC_CLAMP [30:28] OBSLEN
CCDC_CLAMP [27:25] OBSLN
x CCDC_CLAMP [4:0] OBGAIN
Computed offset used here
Masked pixels
Active pixels
Public Version
Camera ISP Functional Description
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Figure 6-79. Camera ISP CCDC Optical Clamp Representation
Black-Level Compensation
After the optical clamp, black-level compensation is applied to the data. In this operation, a fixed value,
depending on the color (R/Ye, Gr/Cy, Gb/G, and B/Mg), can be subtracted from the data. The offset
(
register, fields R_YE, GR_CY, GB_G, B_MG) applied to each data sample is selected
according to the pixel position (0/1/2/3) and the color (0/1/2/3) specified for each pixel position
(
). The color pattern definition is flexible to accommodate different sensor types (such as
Bayer CFA sampling, VGA Movie Mode).
Faulty-Pixel Correction
Faulty-pixel correction in the CCDC module requires the camera driver to have information about the
image-sensor faulty-pixel number and positions. This method leads to the best image quality. However, if
the position of the faulty pixels is unavailable to the camera driver, it can apply another faulty-pixel
correction algorithm in the preview module. This algorithm leads to lower-quality images.
The CCDC module implements an optional (
[15] FPCEN) faulty-pixel correction operation
using a look-up table stored in external memory, which contains information about the horizontal and
vertical positions of the pixels to be corrected, as well as the type of operation to be performed on the
pixels. The
register specifies the starting address in memory for the faulty-pixel
correction table.
NOTE:
The memory address must be 64-byte-aligned (6 LSBs are ignored).
NOTE:
For YUV data, the faulty-pixel correction operation is not applicable and must be
disabled/bypassed (
[15] FPCEN).
1196
Camera Image Signal Processor
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated