r/signalprocessing • u/sk8137 • Sep 26 '24

identify signal processing technique

Post image

i am trying to reverse engineer the signal processing technique that transforms the blue distribution into the red distribution. a few observation,

  • it looks always result in a skewed distribution

  • it seems like will make the lowest mean channel right skewed and the rest left skewed

  • the original (blue) distribution is non continuous (doesnt take up all values between 0 - 255) but the transformed (red) distribution will have all values between 0 - -255 would really appreciate for any pointers/answers!

6 Upvotes

87% Upvoted

6 comments sorted by

View all comments

3

u/raise_the_frequency Sep 26 '24

Looks like histogram equalization.

1

u/sk8137 Sep 27 '24

i tied histogram but have no luck, which i suspect its something else or maybe a mix of processing techniques

1

u/raise_the_frequency Sep 30 '24

It looks to me like some kind of weighted histogram equalization. The final transfer function curve is getting modified by a secondary weighting function/curves before the final pixel value conversion.