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jenny_shoars
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Homework Statement
Prove that a line in 3D space is imaged to a line on the image plane in a pinhole camera model.
Homework Equations
A 3D point give by (X,Y,Z) will be imaged on the image plane at
x = f([itex]\frac{X}{Z}[/itex])
and
y = f([itex]\frac{Y}{Z}[/itex])
where f is the focal point.
The Attempt at a Solution
My first thought was a more intuitive one. If you have a line in 3D space and the point which is the pinhole, you have a plane on which both the pinhole and line lie. Where this plane intersects the image plane it forms a line and this is where the 3D line is mapped to on the image plane. However, this seems like too much hand waving.
Instead I decided to try saying that for the line in 3D there must be a parametric equation given by
X = at + d
Y = bt + e
Z = ct + g
Then
x = f[itex]\frac{at+i}{ct+k}[/itex]
y = f[itex]\frac{bt+j}{ct+k}[/itex]
From here I know that for a line to exist on the image plane there must be a q and m such that
y = mx + q
Yet, this doesn't seem to lead me in the right direction.
Any suggestions? Thank you for your time!