mt9v032 aptina, mt9v032 Datasheet - Page 49

• Manufacturer Part Number: mt9v032
• Description: 1/3-inch Wide-vga Cmos Digital Image Sensor
• Manufacturer: aptina

Row-wise Noise Correction
PDF: 6538045704/Source:2194051501
MT9V022_DS - Rev. C 9/10 EN
Offset Correction Voltage = (8-bit signed two’s complement calibration value,-127 to 127) × 0.5mV
ADC input voltage = (Pixel Output Voltage + Offset Correction Voltage) × Analog Gain
777 < (R0x73, bits 9:0) + number of dark pixels programmed in R0x70, bits 3:0 -1
Pixel value = ADC value - dark column average + row noise constant
The offset correction voltage is generated according to the following formulas:
Row-wise noise correction is controlled by the following registers:
• R0x70 row noise control
• R0x72 row noise constant
• R0x73 dark column start
When the row-wise noise cancellation algorithm is enabled, the average value of the
dark columns read out is used as a correction for the whole row. The row-wise correction
is in addition to the general black level correction applied to the whole sensor frame and
cannot be used to replace the latter. The dark average is subtracted from each pixel
belonging to the same row, and then a positive constant is added (R0x72, bits 7:0). This
constant should be set to the dark level targeted by the black level algorithm plus the
noise expected on the measurements of the averaged values from dark columns; it is
meant to prevent clipping from negative noise fluctuations.
On a per-row basis, the dark column average is calculated from a programmable
number of dark columns (pixels) values (R0x70, bits 3:0). The default is 10 dark columns.
Of these, the maximum and minimum values are removed and then the average is calcu-
lated. If R0x70, bits 3:0 are set to “0” (2 pixels), it is essentially equivalent to disabling the
dark average calculation since the average is equal to “0” after the maximum and
minimum values are removed.
R0x73 is used to indicate the starting column address of dark pixels that the row-noise
correction algorithm uses for calculation. In the MT9V032, dark columns which may be
used are 759–776. R0x73 is used to select the starting column for the calculation.
One additional note in setting the row-noise correction register:
This is to ensure the column pointer does not go beyond the limit the MT9V032 can
support.
50
MT9V032: 1/3-Inch Wide-VGA Digital Image Sensor
Aptina reserves the right to change products or specifications without notice.
©2005 Aptina Imaging Corporation. All rights reserved.
Feature Description
(EQ 12)
(EQ 13)
(EQ 14)
(EQ 15)