What is the use of "threshold_list" in the Lepton_get_object_temp example?

OpenMV Pure Thermal
1

The example shows

Color Tracking Thresholds (Grayscale Min, Grayscale Max)

threshold_list = [(200, 255)]

What does this do? Does changing this value change the output temperature? should not the output temperature be irrelevant of input?
I am using a lepton 2.5.

2

Dear friend.
The camera takes all the temp values and map them to greyscale image. (0-255 values)
0 stands for black (min temp) and 255 for white (max temp)
so if min temp is 20 degrees and max temp is 40 degrees , 128 greyscale value will be the 30 degrees.
Then threshold list is used for blob detection just to track the temp you want.

3

thats wonderful. thank you very much. Can you also tell me how can I extract these grayscale value from an image per pixel.

4

Dear friend in the example you are working is everything.
In addition the program has a script that calculates all these grayscale values of the blob found and exports the estimated temperature in celcius!