Histograms 333

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Histograms in 333 camera

It is now (starting with 6.4.22 software) possible to get images with histograms from the 333 cameras.

histogram.cgi

http://<camera_ip>/histogram.cgi

returns GIF image with 4 histograms - for integral intensity (white) and for individual colors (RGB)

pnghist.cgi

http://<camera_ip>/pnghist.cgi

returns PNG images and can be configured with additional parameters, such as

http://<camera_ip>/pnghist.cgi?sqrt=0&scale=10&average=10

pnghist.cgi parameters

Bold are the default values

height -   image height, maximal is 256 pixels (width is always 256)
draw -     draw mode (0..2): 0 - dots, 1 - vertical bars, 2 - connected dots
fillz -    (0/1), fill zeros - fill gaps of zeros (happens in high contras areas where each sensor count (1 of 1024) corresponds to several output counts. 
linterpz - (0/1), linear interpolation for the filled gaps of zeros. Automatically turns on fillz (above)
sqrt     - (0/1), calcualtes square root fro each histogram value. Relatively increases small values.
colors   - (0..57..63). Bit-mask that controls display of individual and composite components:
1 - red, 2 - Green1 (in red rows), 4 - green 2 (in blue rows), 8 - blue, 16 - white, 32 - both greens combined. So 1+8+32=40 will display R,G and B
average  - (0...) - running average, averages specified number of pixels to make histograms smooth.
scale -   (..3.0...) - specifies what fraction of the total height would the histogram occupy iof all the values were the same. The higher the value, the lower the histogram will be displayed