Content-Aware-Rotation

Reproduction of Kaiming He's Paper Content-Aware Rotation on ICCV 2013.
I just test this project on Windows 10, there may be something wrong on Linux system.

Rotation Manipulation

suppose that :
,
then we have :

further, we can get the derivative :
Line Preservation

suppose that :
,
then we have :

further, we can get the derivative :
Shape Preservation

suppose that :
,
then we have :

further, we can get the derivative :
Boundary Preservation

further, we can get the derivative :
Optimization
Step 1 : Fix θ solve for V
Sparse Linear System :

V is the minimum point of total energy above, thus, let :

we can get the solution for V.
Step 2 : Fix V solve for θ
Part 1 : Fix Φ, update θ

suppose that :

we have :

then let :

by solving a sparse linear system, we can get the solution of θ :

Part 2 : Fix θ, update Φ

the solution of Φ can be easily approximately reached by enumeration based on iteration methods(increase β gradually).

How to Use : download the whole project and run main.py
folder ep : images which are used for formula derivation and some results.
folder image : images which are used in original paper.
folder lsd : line segment detection algorithm in python version.
warp_mesh.py : image warping method realized by embedded function in tensorflow.

Name		Name	Last commit message	Last commit date
Latest commit History 77 Commits
eq		eq
image		image
lsd		lsd
README.md		README.md
boundary_preservation.py		boundary_preservation.py
line_preservation.py		line_preservation.py
lsd_detect_lines.py		lsd_detect_lines.py
main.py		main.py
mesh_segment.py		mesh_segment.py
optimization.py		optimization.py
shape_preservation.py		shape_preservation.py
warp_mesh.py		warp_mesh.py

ForeverPs/content-aware-rotation