Computational Photography in addition to Video: Time-Lapse Video Analysis & Editing Prof. M

Computational Photography in addition to Video: Time-Lapse Video Analysis & Editing Prof. M www.phwiki.com

Computational Photography in addition to Video: Time-Lapse Video Analysis & Editing Prof. M

Alvarez, Tina, Music Editor has reference to this Academic Journal, PHwiki organized this Journal Computational Photography in addition to Video: Time-Lapse Video Analysis & Editing Prof. Marc Pollefeys Dr. Gabriel Brostow Last Time

Glenville State College US www.phwiki.com

This Particular University is Related to this Particular Journal

Today’s schedule Factored Time-Lapse Video Sunkavalli, Matusik, Pfister, Rusinkiewicz, Siggraph 2007 Computational Time-Lapse Video Bennett & McMillan, Siggraph 2007 Video Synopsis & Indexing, Pritch, Rav-Acha, Peleg, ICCV 2007 Time-lapse Photography Definition: when frames are captured at a lower rate than the rate at which they will ultimately be played back. Compare to Slow-motion Bullet-time Examples

Time-lapse Filmmaker’s Challenges Time-lapse Filmmaker’s Challenges Lighting changes (strobing) High frequency motion (missed action) Saturation & exposure Camera motion: intentional or not Triggering / data storage / camera safety Useful Editable Factored Time-Lapse Video Sunkavalli, Matusik, Pfister, Rusinkiewicz SIGGRAPH 2007 Project web page

Remember Intrinsic Images from Video Weiss ICCV’01 Outdoors: More Than Just Color vs Illumination Original No Shadows Given: Daytime, under clear-sky conditions Outdoors: More Than Just Color vs Illumination Original No Shadows Given: Daytime, under clear-sky conditions Wishlist Remove shadows Render new shadows Change albedo Change global illumination

Outdoors: More Than Just Color vs Illumination Original No Shadows Lighting due to sun sky Surface Normals Formulation size: width x height x time F: xyt volume of frames over time Isky: Accumulated intensity due to sky-light Isun: Accumulated intensity due to sun-light Ssun: Binary; is a pixel in shadow Intuition

Separate Sky first Photoshop! Just to pick “non-surfaces” When is sun’s contribution == 0 Leaving just sky’s contribution “Definitely” shadow: median of darkest 20%, then threshold at 1.5x

Bilateral Filter “Definitely” Shadow How Did Skylight Change Isky: Accumulated intensity due to sky-light Wsky: Sky-light image Hsky: Sky-light basis curve (1D function!!) Whole scene got brighter/darker together

Blue: skylight curve (same one) Factorization Decompose appearance into per-pixel W H curve Alternating Constrained Least Squares (ACLS): H(t) is held fixed while W is optimized using least squares, then vice versa ACLS: Alternating Constrained Least Squares Inverse shade trees as long as non-parametric material representation in addition to editing, Lawrence et al., Siggraph 2006, code online

Alvarez, Tina Entertainment Magazine Online Music Editor www.phwiki.com

Original in addition to Isky Isky in addition to Reconstruction

Explained Sky Now Decompose Sun’s Contributions Isun: Accumulated intensity due to sun-light Wsun: Sun-light image, per-pixel weights Hsun: Sun-light basis curve : Shift-map; per pixel offset in time

What to do with blob-tracks (Project web page) HDR Time-Lapse Essentially started in 2006 (manually at first) More are popping up online Discussion

Alvarez, Tina Music Editor

Alvarez, Tina is from United States and they belong to Entertainment Magazine Online and they are from  Tucson, United States got related to this Particular Journal. and Alvarez, Tina deal with the subjects like Music; Music Industry

Journal Ratings by Glenville State College

This Particular Journal got reviewed and rated by Glenville State College and short form of this particular Institution is US and gave this Journal an Excellent Rating.