image stitching: exploring practices, software and performance, d.williams & p. d. burns
DESCRIPTION
Presentation by Don Williams at IS&T's Archiving 2013 ConferenceTRANSCRIPT
![Page 1: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/1.jpg)
DON WILLIAMS; IMAGE SCIENCE ASSOCIATES; WILLIAMSON, NY/US,
PETER D. BURNS;
BURNS DIGITAL IMAGING; FAIRPORT, NY/US
Image Stitching: Exploring Practices, Software and Performance
IS&T’s Archiving 2013 Conference, Washington DC April 2013
![Page 2: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/2.jpg)
Image Stitching
The merging of separate, neighboring digital images of portions of an object into a single, larger digital object. Requires integration of both spatial and luminance image information.
Identified under FADGI gap analysis Increased popularity Are the results as analytically accurate as they appear ?
![Page 3: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/3.jpg)
Categories
High total ownership Research institutes, restoration studios, galleries, museums,
collectors, auction houses Step-and-repeat robotics: SatScan™ Art, ResolutionArt, Google Art Well characterized imaging performance, and mechanical
constraints High value objects
Affordable COTS hardware and software Institutional libraries, small collections, service bureaus COTS hardware and/or software Less calibrated systems, demanding productivity, challenging and
varied content.
![Page 4: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/4.jpg)
Typical Stitching Workflow using COTS resources
Object identified, mechanically constrained and scan parameters selected
Multiple captures performed Manual or mechanical translation 6 - 30 separate captures
Images uploaded to servers or dedicated computer Into the software sausage factory
Results QC’d Redo with new approaches or software parameters if unacceptable
Manually edit in image editors Set limits on time/image Save and move on
![Page 5: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/5.jpg)
Typical Stitching Software Operation
Align – ( seam carving, content aware resize) Identify approximate relative location of the component
images Identify corresponding features in overlap areas Select stitching boundaries and margins Correct for distortion, perspective, intensity differences.
Merge Combine image tiles and create boundaries
![Page 6: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/6.jpg)
COTS Software ?
Choices are overwhelming Developed as creative tools (edit vs. calibrate ?)
Usually yield visually pleasing results but … Pshop Photomerge, Autopano, PTGui Ease of use –
Few excellent results vs. many good ones ? How many choices do you need ?
![Page 7: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/7.jpg)
Good News, Bad News
![Page 8: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/8.jpg)
Synthetic Stitching Experiment
![Page 9: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/9.jpg)
Before Stitching
![Page 10: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/10.jpg)
After Stitching
![Page 11: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/11.jpg)
Steps in Modern Stitching Operations
![Page 12: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/12.jpg)
Low Energy Seam Carving Boundary Path (PhotoShop)
![Page 13: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/13.jpg)
Sources of Variability/Errors
Lens performance Capture conditions
Overlap Rotation, flatness Illumination variability
Mechanics Software complexity Computational power and storage Object characteristics Algorithm idiosyncrasies Operator training
![Page 14: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/14.jpg)
Error Detection/Prevention/Correction
Detection - Visual cueing features Alignment - at seam interfaces Blending – image equalization processing
Prevention & Correction Good image practices and equipment Use simple fill and digital cloning tools Avoid complex operations
![Page 15: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/15.jpg)
Tactical Approaches
Take an incremental approach Observe and benefit from algorithm idiosyncrasies Archive component tiles for future processing Try it again ! Take care in original capture
Placement, hardware Reasonable overlap
Object Triage ? Fragile vs. non fragile Sizes ?
![Page 16: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/16.jpg)
Alternative Solutions
Large flatbed scanners Cruse Zuetschel I2S
Large Sheet Fed scanners WideTek 36DS, etc. Contex
![Page 17: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/17.jpg)
Conclusions
Most Automerge tools do a good first order job, but …… Visually appealing results ≠ Spatially accurate results. Good imaging practices and moderated image processing
( lens and lighting profiles) can reduce geometric distortions significantly.
Most errors tend to be due align rather than merge operations.
Keep post processing edits simple. Better full reference distortion metrics needed to assess
stitching goodness.
![Page 18: Image Stitching: Exploring Practices, Software and Performance, D.Williams & P. D. Burns](https://reader033.vdocument.in/reader033/viewer/2022060200/5598b94d1a28abb24a8b45c2/html5/thumbnails/18.jpg)
Gratitudes
Dave Mathews, Image Collective Northwestern University
Stanford University, Green Library Jeff Chien, Adobe Systems Inc.
For more information contact: Don Williams or Peter Burns