i like to get the area from a surface. this surface is an image. only black or white. no grayscale. i need the area of just the black or just the white. since i have alot pictures i want to analyse, i like to use grasshopper.
i saw there are different options in rhino to analyse an area.
what do you think is the most promising approach?
Is there a specific reason why this should happen in grasshopper? photoshop can do this (as a percentage of the image’s pixels)
Do you actually need the shape of the area, or just its measure? It’s always a little tough to translate bitmap to vector information. I’d use the image value to displace a mesh in the Z direction, then cut a contour through the resulting mesh at a height corresponding to the brightness value you want. Here’s a super simplistic approach. If you need closed regions you’ll need to get a little more sophisticated:
thanks for the answer.
well if photoshop can give me an excelfile i would gladly do it with PS. i couldnt find it with PS as well.
And if you just want the area, in pixels, you could do something like this:
well, It is not a GH related answer but l hope the admins won’t be too strict with me!
Look for this:
Percentile: Displays the cumulative number of pixels at or below the level underneath the pointer. This value is expressed as a percentage of all the pixels in the image, from 0% at the far left to 100% at the far right.
edit: …or you can do what @andheum said! (my god! you never know what you will learn in this forum!!!)
thanks. ill try to wrap my head around it.
thanks. any idea how to get those infos as data?
oh and that panel that says “black pixels” should just say total pixels my mistake
No, and after seeing Andrew’s script I wouldn’t even bother!
One more approach - I like this one because it shows how to do many images at the same time, and allows you to set a sample resolution (by changing the slider going into X + Y of the IMG component)
since you did it, why don’t you upload it?
I wanted to experiment with it just out of curiosity
Sure. Requires Human for the Directory Contents component. Image Areas.gh (12.0 KB)
Human.gha (414 KB)