video stabilization
play

Video Stabilization CS448V Computational Video Manipulation April - PowerPoint PPT Presentation

Video Stabilization CS448V Computational Video Manipulation April 2019 Fundamental problem that became even more relevant in recent years Important for producing high quality video and as a first step of many algorithms Important for


  1. Optimizing a single path Data term: 
 blue should match red Smoothness term: 
 t blue at time t should match the (60) frames around t min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term

  2. Detour: bilateral filter Slides adapted from Sylvain Paris

  3. Objective of bilateral filtering • Smooth texture • Preserve edges

  4. Illustration in 1D

  5. Illustration in 1D 1D image = line of pixels

  6. Illustration in 1D 1D image = line of pixels Better visualized as a plot pixel intensity pixel position

  7. Definition

  8. Definition Gaussian blur p I p = ∑ G σ s ( ∥ p − q ∥ ) I q q q only spatial distance, intensity ignored space

  9. Definition Gaussian blur p I p = ∑ G σ s ( ∥ p − q ∥ ) I q q q only spatial distance, intensity ignored space Bilateral filter p [Aurich 95, Smith 97, Tomasi 98] I p = 1 range W p ∑ G σ s ( ∥ p − q ∥ ) G σ r ( | I p − I q | ) I q q q spatial and range distances space

  10. Example on a real image Ä Ä Ä

  11. Bilateral filter is not just for pixel values!

  12. Bilateral filter is not just for pixel values! Back to stabilization…

  13. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term

  14. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term ω t , r = G t ( ∥ r − t ∥ ) ⋅ G m ( ∥ C ( r ) − C ( t ) ∥ )

  15. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term ω t , r = G t ( ∥ r − t ∥ ) ⋅ G m ( ∥ C ( r ) − C ( t ) ∥ ) distance between frames

  16. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term distance between camera poses ω t , r = G t ( ∥ r − t ∥ ) ⋅ G m ( ∥ C ( r ) − C ( t ) ∥ ) distance between frames

  17. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term setting the weights λ t

  18. Optimizing a single path min ∑ ∥ P ( t ) − C ( t ) ∥ 2 + λ t ∑ ω t , r ( C ) ⋅ ∥ P ( t ) − P ( r ) ∥ 2 r ∈Ω t t data term smoothness term setting the weights λ t Run optimization with global weight For each frame While too much cropping or distortion Decrease weight and re-run

  19. Optimizing bundled paths

  20. Optimizing bundled paths single path smoothness between neighboring paths min ∑ O ({ P i ( t )}) + ∑ ∑ ∥ P i ( t ) − P j ( t ) ∥ 2 j ∈ N ( i ) i t i N(i)

  21. Calculate relation Smooth relation Create frames using Detect features between photos between photos smoothed relation Input Output frames frames warping-based adaptive space-time motion path smoothing representation

  22. Evaluation & Results

  23. Comparison to previous methods

  24. Comparison to commercial products

  25. User study

Recommend


More recommend