Introduction to the Image API given at the IIIF Workshop in South Africa. Workshop available at: https://iiif.github.io/training/iiif-1-day-workshop/

1. IIIF Image API
Glen Robson IIIF Technical Coordinator
@glenrobson

2. Introductions
● Name
● Institution
● What do you hope to learn?

3. About me
IIIF Technical Coordinator
● Help with implementations
● Work with vendors
● A community resource
Previously at the National Library of Wales for 12 years
● Digitisation
○ http://bit.ly/2zPFx8a
● Newspapers
○ http://newspapers.library.wales
● Fedora Repository
● Crowdsourcing
● Developed a IIIF image server

4. Introductions
● Name
● Institution
● What do you hope to learn?

5. Plan
● Where did the IIIF Image API come from?
● Using the IIIF Image API
● Creating IIIF Image APIs
○ Hosted
○ Cantaloupe
○ Static - if time

6. IIIF APIs

7. Why invent an Image API?

8. From Ben Albritton’s blog http://stanford.io/1PW789d

9. Image files
Thumbnail Web copy Archival copy

10. Problems
● New developments like Mobile
○ More files to manage
● Web copy too low resolution for researchers
● Archival copy to big for everyone

11. Solution: Zoomable images!

12. Problems - with zoomable images
● New developments like Mobile
○ Flash based viewers
● No way to download images for researchers
○ Some saw this as a positive
● Proprietary viewers and file formats
○ Zoomify file format: pff
○ Zoomify viewer

13. What I[II]F?
● Access images at different sizes
● Only manage 1 file
● Mobile accessible viewers
● Format agnostic
● Zooming viewer
● Pick and choose viewer
Plus extras:
● Citeable URL
● ‘Super slippy viewer’ - Tom Cramer

14. IIIF Image API
http://iiif.io/api/image/2.1/

15. Example
https://tomcrane.github.io/the-long-iiif/image-api.html
John Dee performing an experiment before Queen Elizabeth I. Oil painting by Henry Gillard Glindoni.
Wellcome Library:
http://wellcomelibrary.org/item/b14658197
From: http://resources.digirati.com/iiif/an-introduction-to-iiif/

16. What I[II]F?
● Access images at different sizes
● Only manage 1 file
● Mobile accessible viewers
● Format agnostic
● Zooming viewer
● Pick and choose viewer
Plus extras:
● Citeable URL
● ‘Super slippy viewer’ - Tom Cramer

17. Zooming

18. IIIF Zoom
http://tomcrane.github.io/presentations/tile-exploder.html

19. How does the viewer know whats available?
info.json

20. How does the viewer know whats available?
info.json
@id: the URL for this image. Put this link into your
browser and you should get this file
Protocol: always iiif
Width and height of the largest image or x and y in
the diagram.

21. How does the viewer know whats available?
info.json
Tiles:
Width and height of each little box
- Usually standard 256 or 512
ScaleFactors
- This image has 4 levels
- Their sizes are:
- Full size - 1
- ½ size - 2
- ¼ size - 4
- ⅛ size (thumb) - 8
These are usually configured when generating the source
image.

22. How does the viewer know whats available?
info.json
What sizes does the server have that you can
request e.g.:
http://server/iiif/image/full/1024,651/0/default.jpg
These are usually a copy of the zoom levels but
could be others of efficiency. E.g. Commonly
used thumbnail sizes (mirador)

23. How does the viewer know whats available?
info.json
What the image server supports
- E.g. Format types that can be returned
- Extra optional functionality
Levels
- Level 0 - only specific sizes and tiles available
- Level 1 - Any size or tile image available,
- Level 2 - all of the above and many optional
features

24. IIIF Zoom
https://tomcrane.github.io/the-long-iiif/dee-osd.html

25. IIIF Validation Image
● http://iiif.io/api/image/2.1/example/reference/67352ccc-d1b0-11e1-89ae-
279075081939
● Questions:
● How do we find the width and height?
● How do we view the full size image?
● What URL do we need to get the top left square?
● How about the yellow one?
● Can we rotate it 45degrees?
● Greyscale?

26. Exercises
Have a look at Jason Ronallo’s ‘Detailed Example’
http://ronallo.com/iiif-workshop/image/detailed-example.html
Play with Tom Cranes examples:
https://tomcrane.github.io/the-long-iiif/image-api.html
Have a look at the UCD image cropper:
https://jbhoward-dublin.github.io/IIIF-imageManipulation/index.html?imageID=https://iiif.ucd.ie/loris/ivrla:10408
In pairs do the gitbook exercises
If you finish have a look at:
http://puzzle.mikeapps.me/

27. What I[II]F?
● Access images at different sizes
● Only manage 1 file
● Mobile accessible viewers
● Format agnostic
● Zooming viewer
● Pick and choose viewer
Plus extras:
● Citeable URL
● ‘Super slippy viewer’ - Tom Cramer

28. Format Agnostic
● In the IIIF Image API there is no reference to source image
● Different image servers support different image types.
● Most popular:
○ JPEG2000 / jp2
○ TIFF

29. Pyramid images formats
● JPEG2000 / jp2
○ Better compression
○ More efficient file format
○ Mathematically complicated compression
● Pyramid TIFF
○ Simple to process
○ Large file sizes

30. What, IIIF!
IIIF Image API Benefits
● Access images at different sizes
● Zooming viewer
● Pick and choose viewer
● Citeable URL
Web developments
● Only manage 1 file
○ jp2 / pyramid image files
● Mobile accessible viewers
○ Javascript Browser support
● Format agnostic
○ Image servers developers / Image API

31. IIIF Comercial Image Servers
Ideally integrated into Institutional Image Management System
● Content management system
○ V&A Uk extending their CMS
● Digital Asset Management system
○ Rosetta ExLibris
○ Content DM OCLC
○ Luna Imaging
○ Africa Media Online MEMAT
● Repository
○ Fedora
○ DSpace
● Question: Where does your institution store its Images?

32. IIIF Image Servers - Hosting
IIIF Hosting
● Klokan: https://www.iiifhosting.com/
● Digirati: https://dlcs.info/
Advantages:
● Easy to use
Disadvantages:
● Cost
Exercise: https://iiif.github.io/training/iiif-5-day-workshop/day-one/iiif-hosting-saas.html

33. IIIF Image Servers - level 0
Split large images into tiles and save as jpgs
Advantages
● Free (requires webspace)
● Fast
● Scalable
Disadvantages
● Complicated compared to other options
● Not all viewers work with a level 0 image
Exercise: https://iiif.github.io/training/iiif-5-day-workshop/day-one/level0-github-hosting.html

34. IIIF Image Servers - Image Server
https://github.com/IIIF/awesome-iiif#image-servers
● IIP Image - written in C
● Loris - python
● Cantaloupe - Java
Advantages
● Flexibility
● Fully compliant
● Scalable
Disadvantages
● Requires running a server or servers
Exercise: https://iiif.github.io/training/iiif-5-day-workshop/day-one/setting-up-cantaloupe.html