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mstg007

Measure Distances from a Photo

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mstg007

What Could I use to get measurements from existing photos (jpgs)?

 

 

If I take a photo of a house where I can see the front and side of it. How can I get the length and width of the house? (with a known height of an object already in the photo)?

 

 

Sorry it I confused you if I did.

 

 

Thanks!

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Dana W

It doesn't really work at all, especially knowing only one distance.

 

Every single line in a photo is foreshortened due to perspective. Even if you were to scale the photo by reference using the known object, that would be the only distance that would be at 1:1 scale, and ONLY that distance, at that one single location.

 

The variance from scale increases by a negative number (gets shorter) for everything that is further away from the camera than the referenced object, and increases by a positive number (gets longer) for everything that is closer to the camera than the referenced object. Nothing, repeat nothing, in a photo can be considered parallel with the camera viewing plane.

 

Lets say the known distance is the height of one porch post. Only the one single point on the porch post that was exactly perpendicular to the camera lens center point is accurate. Everything in all directions from that point is not at the same scale ratio as that point, and points aren't very large at all. This problem is made worse by camera lenses not having the same focal length. Each different focal length has its own perspective.

 

This is why nobody can say how tall Bigfoot really is. :) ;)

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lrm

You could try using the

feature of 3ds Max. Once you have the camera location you can create a boxes to represent the basic shape of the house and manipulate it to fit the scene. Since you know one of the real dimensions you can use that to appropriately scale the other dimensions of the boxes.

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mstg007

Thank you for all the input guys. Thought I ask.

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