The links at the bottom of the Wiki page on Perceptual Hashing are good (pHash looks promising)
RGB → HSV (which includes Hue) = HSL and HSV - Wikipedia
I’m going to add HSV to my analysis as a result when the renders have finished (ETA 1:26:09 - can’t wait…)
Dunno if you know this site but it might be of useful to you “http://colorizer.org/” use one color format ie: RGB for example and get all the different variants related to color as for the wiki link thanks seems I had it already in my bookmarks just had forgotten about it. Now if the styles.list wasn’t encrypted I could pull off a better stunt by adding all 16 million colors into the add-ons list by script as using pure colors gives a interesting effect in regards to final results guess I’ll just keyboard mouse macro it to add it to the pack. As for 1 1/2 hours to get results that’s not bad at all good luck with the results maybe you’ll get lucky on something useful.
Definitely need someway to sort out these images
The most colourful (as currently measured - changing this soon) is…
Yuck - this is fully transparent if you remove background on it
Searching for transparency > 1/2 the most colourful is sorta human-ish (but his head is missing)
Ooh - checking my code the colour number is good. I forgot how I’d decided to assign this one. I create a 512 palette then count how many were actually used at all - so it’s the number of different colours in the image on a scale from 0 - 1. The bad thing about this measure is that if you had a completely white image with 511 pixels that just happened to be the other colours then it’d come out as 0.5 - this needs weighting…
Finished (whew) 100k images done - if I’d run it all on the slower PC it would have taken just over 12 days 24/7
@Peardox Indeed weighting would do it or converting the image to 1x1 pixel and getting that value would give you the average color value to be able to sort I have a few tools I use Color quantizer 0.7.4.4 for Windows, ImageResizer-r133, and imagemagick when I’m digging for colors or patterns but code wise with php should be a breeze to check that type of info in a reasonable timely matter. I’ll see what I can pull off and post some results.
I just had a wonderful idea to help visualise the data I’m currently calculating. Convert it to a ‘Skymap’.
Here’s a 2D test I did before I thought of this idea…
This one’s cover (background removal) vs light (brightness of image from b+w conversion)
If you imagine that these were stars and add a third metric then chose a point of interest as ‘Home’ then it is possible to map the entire shebang onto a sphere and view it as a night sky from ‘Home’
You could also ‘Travel’ to another ‘Planet’ and view the ‘sky’ from there.
Have you heard of anything that does this? It seems like a really simple and obvious idea - someone’s bound to have thought of it before me (which will save me having to work all the math out)
Calculating the mapping of 100k points to a sphere sorta sounds time consuming as there’ll be a lot of trig (sin, cos etc) calculation involved.I’m not overly sure how fast it’d be to ‘travel’ (that’s when you’d have to re-calculate all the numbers)
I sorta find the idea of a night sky where all the ‘Stars’ are actually images you can look at through a ‘Telescope’ rather appealing as a concept.
[Edit] Ooh - apparently if you look at the sky at night you can only see about 2.500 of them - the maths seems more doable in real time now 
[Found something promising for prototyping the idea]
@Peardox what you are asking is image positioning only tool I’ve seen able to do that is imagej myself personally I use it for the Fast Fourier Transforms (FFTs) and I work with intensities, give me the week-end I know a few people that may have more info on what you are looking for to do heck I’m sure I’ve seen something like this on Windows 3.1 way long time ago, the days where logo writer (That turtle thing) was popular. Would definitely open option in regards to neural style placements but I think depending on the sample one would end up with data collisions. As for Stellarium I have it in my collection a long time ago I’m a fan of sourceforge, itch.io and github (I used to enjoy the google repository before they shut it down) I’m looking in my collection for image generators to suggest for people to use as styles I’ll have a list of tools by next week.
P.S: With Stellarium I made a few gifts using a dot matrix printer and some aluminum paper (Custom birth date constellations with lighted backdrops) until the printer heads we’re finished.
I’ve got something in prototype that’s reasonably fast for visualising the point map now (googling point map - which is what I’ve got - was useless as well)
After half a dozen tries I’ve finally got something that does hue fairly well. Basically I build a historgam of colours used in the image then find the one with the highest count. I’ve also fudged the colours to reduce the possibilities from 16M to 512 when working the hue out.
It’s not perfect but it’s an acceptable way to classify an image as being mostly hex XXXXXX in colour.
Four hours to process them all 
Webpage testing
You Crazy! 
Loving it.
But indeed that definitely works. This is what I had found for the histogram that worked best for me Fred's ImageMagick Scripts: SPECTRUMHIST but seems you’ve figure out the best results for PHP use.
