Shad-o-Scan 3001/4501 User Manual (Draft)
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Teledyne DALSA
Separate defect pixel maps are available for different Readout- and Full Well modes.
These maps are used by the detector to apply DPC on images, before streaming them
over the data communications interface.
The defect map can be used by the host application to apply corrections for defect pixels
in images captured from the detector.
The host application may use the “Teledyne X
-Ray
Processing Library” functions to apply such corrections, or for the creation and uploading
of new correction maps. This library and its API can be downloaded from the Teledyne
DALSA FTP server (ftp.teledynedalsa.com) on request.
DPC Calculation
The pixel value after DPC correction is interpolated from an analysis of neighboring pixel
values in a 5x5 kernel. Interpolation is performed in the direction in which the image
content shows the least amount of change within this kernel.
File Format
The file format of a defect map is as follows: A header indicates the specification of the
defect map, and will be followed by a data block with the defect information per pixel.
Only one bit per pixel is used to indicate the defect status (0 = no defect, 1 = defect). The
defect status data per pixel is ordered row-by-row, left-to-right and top-to-bottom in an
image displayed on a computer screen). The 32 bytes header format is described below:
Field
Description
Endian Bytes
Header Version 0 Version number
2
Serial Number
Serial Number of Detector
16
CRC
CRC16 of total data file without the header
Little
2
Width
Number of columns (of full resolution image) Big
2
Height
Number of rows (of full resolution image)
Big
2
File Type
0 Full Resolution, High Full Well
1 Full Resolution, Low Full Well
2 Binning 2x2, High Full Well
Big
2
