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Bad Pixel map edition
Firmware version 1.1.0 introduces the possibility to modify the bad pixel map embedded in the camera.
The camera now contains two bad pixels map, a factory map built by First Light Imaging during the
production of the camera and a customizable user map. The user map is by default identical to the
factory map.
The user bad pixel file can be retrieved using the following commands
-
recv userbadpixel size
returns the size in byte of the user bad pixel map
-
recv userbadpixem md5sum
returns the md5sum of the user bad pixel map
-
recv userbadpixel content
returns the content of the user bad pixel map
The factory bad pixel file can be retrieved using the following commands
-
recv factbadpixel size
returns the size in byte of the factory bad pixel map
-
recv factbadpixem md5sum
returns the md5sum of the factory bad pixel map
-
recv factbadpixel content
returns the content of the factory bad pixel map
Bad pixel size and md5sum allow to ensure that the bad pixel map has been received successfully.
The transfer is done in raw mode on the serial connection with the camera.
The user bad pixel map can be sent using the command
sendfile userbadpixel <size> <md5>
command. The transmission is done in raw mode on the serial connection with the camera.
Restoring the factory map can be easily done by reading the factory bad pixel and storing it in the
camera.
The bad pixel map is a file of 40960 bytes (640*512/8). Pixels are described from the top left pixel to the
right bottom pixel of the sensor.
Each byte represents 8 successive bad pixels, most significant bit corresponding to the left pixel, and
least significant bit corresponding to the right pixel. Valid pixels are set to 0, whereas invalid pixels are
set to 1.
Example: most significant bit (bit 7) of the first byte of the file corresponds to the first pixel of the first
line of the sensor. Least significant bit (bit 0) of the first byte of the file corresponds to the 8
th
pixel. Most
significant bit of the second byte of the file corresponds to the 9
th
pixel of the first line. And so on…
The format of the bad pixel map corresponds to standard 1-bit depth black and white image that can
be easily manipulated by imageJ (
) software.
