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/sci/, I'm stumped. I need to figure out how to determine dimensions of a 3d object in a photograph based on a know dimension and some assumptions.
For this prism, I figured it might be possible to determine the angles relative to the X (horizontal) and Z (into the page) axes that the part is rotated, and scale my measurements by factoring in the angles. But I'm having trouble figuring out how to effectively find the angles relative to these axes and thus figure out how dimensions scale across the length, width, and height of the object.
I'm going off the assumption that the part is small enough that focal length doesn't introduce a large amount of error, and that i know the height (along the vertical axis) of the prism.
tl;dr i'm dumb, plz help
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>>9035015
Use math dummy. Fucking brainlets, when will they ever learn?
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photogrametry
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>>9035030
that's not an answer you little shit
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>>9035015
Why not just shift the x y plane to make it easier on yourself
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>>9036105
Then I have to know the height and width of the prism
i'm pretty sure
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>>9035015
>x horizontal
>z into the page
Your coordinate system is all fucked bud
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>>9035015
Pixelmeasurements!
Pixelmeasurements...
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>>9036709
wut
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>>9035015
Wait what info did you start of with?
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>>9035015
>I need to figure out how to determine dimensions of a 3d object in a photograph
Good luck, dummy.
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>>9038454
Well I'm trying to find a technique to do this for a number of different parts, but generally I start off with knowing the width, height, or both (basically the dimensions of the front face), and I can make the assumption that the part stays uniform in shape over its length.
Example: In pic related, I know the diameter of the piece outlined by the yellow square, as well as the length of the black piece behind it. As well, I know the width and height of the red square. I figure using these known dimensions, I may be able to find a correction factor for other dimensions in this picture.
Thread posts: 12
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Thread images: 4