ALLIED Vision Technologies Pearleye P-030 LWIR User Manual
Page 37
Image processing
Pearleye Technical Manual V2.2.1
37
Short introduction: Two-point correction
(A, B, E, J, K, N)
The two-point correction is the most elaborate correction module of the
Pearleye P-007 LWIR / Pearleye P-030 LWIR camera models. For this reason
initially a general survey of the two-point correction functioning shall be given.
By means of the two-point correction (also called gain offset correction) the dis-
tinctive underground structure of the microbolometer sensor can be equalized.
The target is to transmit the individual characteristic curve of each pixel to a set
characteristic curve, being valid for all pixels. In order to achieve this, the effec-
tive characteristic curve of each single pixel is determined by taking up data
samples. A linear characteristic curve is supposed so that two data samples are
sufficient for a definite determination. By means of recording two reference
images at the scene temperatures T
A
and T
B
the data samples can be determined
for all pixels. Furthermore, the digital set values J and K each belonging to the
temperatures T
A
and T
B
are determined.
Owing to the four parameters mentioned above, the two-point correction is now
able to modify the gain and the offset of each pixel characteristic curve in a way
that it is congruent with the set characteristic curve. In a best-case scenario a
structural pattern overlaying the image and caused by the sensor will be fully
eliminated. The below mentioned diagram tries to exemplary explain the facts
on the basis of one single pixel characteristic curve:
Note
For more information see Chapter
Note
For more information see Chapter
This will probably be sufficient for most users, due to the fact
that the determining and adjustment of nearly all parameters
is already executed ex factory and normally no user interven-
tion is necessary at all.
For more extensive details of the current parameters see Chap-
ter