Geometric Computer Vision: Difference between revisions
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==Stereo== | ==Stereo== | ||
===Parallel Cameras=== | |||
Consider two cameras, where the right camera is shifted by baseline <math>d</math> along the x-axis compared to the left camera. | Consider two cameras, where the right camera is shifted by baseline <math>d</math> along the x-axis compared to the left camera. | ||
Then for a point <math>(x,y,z)</math>, | Then for a point <math>(x,y,z)</math>, | ||
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Thus, the stereo disparity is the ratio of baseline over depth: <math>x_l - x_r = \frac{d}{z}</math>. | Thus, the stereo disparity is the ratio of baseline over depth: <math>x_l - x_r = \frac{d}{z}</math>. | ||
With known baseline and correspondence, you can solve for depth <math>z</math>. | With known baseline and correspondence, you can solve for depth <math>z</math>. | ||
===Epipolar Geometry=== | |||
# Warp the two images such that the epipolar lines become horizontal. | |||
# This is called rectification. | |||
===Rectification=== | |||
# Consider the left camera to be the center of a coordinate system. | |||
# Let <math>e_1</math> be the axis to the right camera, <math>e_2</math> to be the up axis, and take <math>e_3 = e_1 \times e_2</math>. | |||
==Projects== | ==Projects== |