image blendingkylexu.net/wp-content/uploads/2016/09/image-blending.pdf · lk α k = ----- d lk + d...
TRANSCRIPT
Kyle Xu
10/16/2014
Image Blending
• Simple to Advanced Approaches – Alpha Blending – Image Feathering – Pyramid Blending
• Applications
• Envision
Agenda
The simplest solution - Alpha Blending
Ioverlap = α x Ileft + (1 - α) x Iright
α = .2 α = .4 α = .6 α = .8
Center Pixels > Edge Pixels
A
At position A:
Pixel from the left Image - Close to the edge - Less contribution to the perception
Center Pixels > Edge Pixels
A
At position A:
Pixel from the left Image - Close to the edge - Less contribution to the perception
Pixel from the right Image - Far from the edge - More contribution to the perception (Close to the center)
Using local alphas – Feathering
Ioverlap = αlocal x Ileft + (1 - αlocal) x Iright
Distance Transform
DL1 DL2 DL3
DR1 DR1 DR3
DLk αk = ----------------------- DLk + DRk
Different Window – Different Result
+
Window 25 Pixel 50 Pixel 200 Pixel
Smaller Image = Harder to tell differences
2 2 2
Lost details at each step: Laplacian Pyramid
2Σ
Lossless Recovery
2Σ 2Σ
Pyramid Blending – Multi-resolution
Apple Laplacian Pyramid
Orange Laplacian Pyramid
+
+
+
Blend Laplacian Pyramid
+
2
Σ
2
Σ
2
Σ
Pyramid Blending – Better Result
+
Feathering Pyramid
Macro & Micro Panoramic
Panoramic Picture of Mars’ Surface
Conclusion
• Alpha Blending: Simplest Solution
• Image Feathering: Good for stitching
• Pyramid Blending: Good for creating
• More advanced algorithm: Poisson Blending
Panoramic Picture of Mars’ Surface
FunPlace!
1. Burt,PeterJ.,andEdwardH.Adelson."TheLaplacianpyramidasacompactimagecode."CommunicaAons,IEEETransacAonson31.4(1983):532-540.
2. hNp://graphics.cs.cmu.edu/courses/15-463/2005_fall/www/Lectures/Pyramids.pdf
3. hNp://compvisionlab.wordpress.com/2013/05/13/image-blending-using-pyramid/
4. hNps://www.youtube.com/watch?v=NiGcuurpV5o&feature=plcp
5. hNps://www.facebook.com/photo.php?\id=10151443406289338&set=a.10150895951034338.524501.776664337&type=1&theater(PhotoshoppedbyZchBielak)
6. hNp://cs.brown.edu/courses/cs129/results/proj2/baebi/7. hNp://cs.brown.edu/courses/cs129/results/proj2/marroz/
8. AirandSpaceMuseuminWashingtonD.C.
References