wassname/scikit-image
1
0
Fork 0
mirror of https://github.com/wassname/scikit-image.git synced 2026-08-05 13:21:12 +08:00
Code Issues Packages Projects Releases Wiki Activity

Document difference between Euclidean and similarity transformation

Browse Source
This commit is contained in:
Johannes Schönberger
2016-06-21 22:39:54 +02:00
parent df2b560acd
commit b7695470ba
1 changed files with 11 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files
skimage/transform/_geometric.py
+11 -3
View File
@@ -657,6 +657,10 @@ class EuclideanTransform(ProjectiveTransform):
[b0 a0 b1]
[0 0 1]]
The Euclidean transformation is a rigid transformation with rotation and
translation parameters. The similarity transformation extends the Euclidean
transformation with a single scaling factor.
Parameters
----------
matrix : (3, 3) array, optional
@@ -739,17 +743,21 @@ class SimilarityTransform(EuclideanTransform):
"""2D similarity transformation of the form:
X = a0 * x - b0 * y + a1 =
= m * x * cos(rotation) - m * y * sin(rotation) + a1
= s * x * cos(rotation) - s * y * sin(rotation) + a1
Y = b0 * x + a0 * y + b1 =
= m * x * sin(rotation) + m * y * cos(rotation) + b1
= s * x * sin(rotation) + s * y * cos(rotation) + b1
where ``m`` is a scale factor and the homogeneous transformation matrix is::
where ``s`` is a scale factor and the homogeneous transformation matrix is::
[[a0 b0 a1]
[b0 a0 b1]
[0 0 1]]
The similarity transformation extends the Euclidean transformation with a
single scaling factor in addition to the rotation and translation
parameters.
Parameters
----------
matrix : (3, 3) array, optional