Reverse engineering of an image filter -


i beginner in image processing , trying reverse engineer application . problem have image before converted image after. discovered whole process done using 256x256 png map overlay map. can understand how can simulate process or algorithm has been used?

edit: have discovered after 256x256 map image overlay overlayed. edit2: forgot app instagram

if pixel pixel operation (namely, works on each pixel independently of other pixels) , have access filter can create lut mimic it.

for instance, 8 bit rgb image create image $ {2}^{24} $ pixels every combination of rgb values.
apply filter on , keep result lut.
given image every pixel has corresponding value on lut , there have result.

enjoy...


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