How i think Portico's Image Algorithm works

[LumiaChemist]

First of all, hi

Since Nokia puplished the portico update and with it the new image processing algorithm i was curious how they managed to do that.
I tested a lot of things but yesterday i think i found the answer.
Click on the pictures and on the website which appears again on the image to view them in 100%.


Thats an image after the portico update.
While we are at it i apologize for some of the following really ugly images




note the pixel-level structure of these branches.


same structure is found in these following leaves.


and again, here




This is the same scene and almost the same perspective without the portico update.



here the pixel-level structure is frazzled and nothing like the smooth and direct borders from the portico pixel-structure.




In the following steps i took the picture from before the portico update resized it, sharpend the result and used an anisotropic filter.
Downsampled the image to the source resolution and added some noise to give it a natural appearence.
The result isnt perfect but nokia for sure dont use adobe photoshop to process the image, they may use an adaptive anisotropic filter to achieve better performance.
(Also i played with temperature contrast and exposure to approach the same overall look of the image with the portico update)



and after some noise:




here the pixel-structure in detail.



before portico and "porticoed"


before portico and "porticoed"



The only problem i have with the way i think portico works is the noise in lumia 920 images. The noise is the only thing which speaks against an anisotropic filter.
If indeed nokia uses an anisotropic filter to get rid of the fuzziness introduced through small pixel size its a rather smart way of doing it.

 

[Andreas H]

Man, you've got too much spare time No offense.