Famous Images in Computer Graphics & Image Processing Sérgio Leal N.o Erasmus student at: Institute for Computer Graphics and Vision Technical University of Graz

Introduction Stanford’s Bunny Stanford’s Bunny Lena Lena The teapot The teapot

Why? Why the same images are always used ? Why the same images are always used ? Which properties have this images that make them special ? Which properties have this images that make them special ? Which properties should candidate images have ? Which properties should candidate images have ?

Stanford’s Bunny Created by Greg Turk and Marc Levoy. Created by Greg Turk and Marc Levoy. Developed to create polygonal models from several range scans. Developed to create polygonal models from several range scans.

Stanford’s Bunny Original paper – Original paper – "Zippered Polygon Meshes from Range Images" Greg Turk and Marc Levoy Siggraph 94, pp On-line version of paper available

Why Stanford’s Bunny? Fairly smooth, Fairly smooth, Has manifold connectivity, Has manifold connectivity, Original was red and diffuse Original was red and diffuse Not complex (69,451 triangles). Not complex (69,451 triangles).

Stanford’s Bunny Curiosities Chosen by chance at Easter time on a shop Chosen by chance at Easter time on a shop Made of terra cota Made of terra cota Original still lives at Stanford Original still lives at Stanford No bottom No bottom

Lena or Lenna Widely used standard test images Widely used standard test images Used for compression algorithms Used for compression algorithms Swedish woman named Lena Sjooblom Swedish woman named Lena Sjooblom Digitized from Playboy centerfold, from November Digitized from Playboy centerfold, from November 1972.

Lena or Lenna Digitized at the University of Southern California as one of many possible images for use by the research community. Digitized at the University of Southern California as one of many possible images for use by the research community. Other examples Other examples

Lena or Lenna Unhappy people about the source Unhappy people about the source Some controversy Some controversy Degrading to women Degrading to women Playboy’s copyrights Playboy’s copyrights

Why Lena? Shading, Shading, Texture, Texture, Flat regions, Flat regions, Nice mixture of detail, Nice mixture of detail, Good for testing various image processing algorithms. Good for testing various image processing algorithms. The Lena image is a picture of an attractive woman. The Lena image is a picture of an attractive woman.

Lena curiosities Married and lives in south Stockholm Married and lives in south Stockholm The image appeared in the movie Sleeper The image appeared in the movie Sleeper Didn’t know how famous her picture was Didn’t know how famous her picture was

Lena curiosities Made her first public appearance in 1997 at the 50th Annual Conference of the Society for Imaging Science in Technology Made her first public appearance in 1997 at the 50th Annual Conference of the Society for Imaging Science in Technology Nowadays helps handicapped people work on (non-networked) computers Nowadays helps handicapped people work on (non-networked) computers

The teapot Done by Martin Newell Done by Martin Newell Suggested by his wife Suggested by his wife Due to lack of computer models Due to lack of computer models Also digitized a spoon and a cup and saucer. Also digitized a spoon and a cup and saucer.

The teapot The original teapot is about 30% taller The original teapot is about 30% taller Jim Blinn, to make the model conform to the pixel raster, squashed the model instead of scaling the image. Jim Blinn, to make the model conform to the pixel raster, squashed the model instead of scaling the image.

Why the teapot ? Instantly recognisable, Instantly recognisable, Complex topology, Complex topology, Self-shadows, Self-shadows, Hidden surface, Hidden surface, Convex and concave surfaces Convex and concave surfaces ‘Saddle points'. ‘Saddle points'. Few storage space Few storage space

The teapot curiosities The original is at Ephemera collection of the Computer History Museum

The teapot curiosities The original teapot data has no bottom. The original teapot data has no bottom. Martin Newell at SIGGRAPH in middle 80 regretted that from all the work he had done, the only thing he will be remembered for is "That Damned Teapot". Martin Newell at SIGGRAPH in middle 80 regretted that from all the work he had done, the only thing he will be remembered for is "That Damned Teapot". Rumours say that the early computer graphics pioneers could type the teapot by memory Rumours say that the early computer graphics pioneers could type the teapot by memory

Conclusion Usually chosen by chance Usually chosen by chance After characteristic noticed After characteristic noticed Gain a sentimental value Gain a sentimental value No special selection algorithm No special selection algorithm Keep trying new ones Keep trying new ones

References University of Southern California image database: University of Southern California image database: Girl - Girl - Couple - Couple - House - House - Tree - Tree - Lena - Lena - Other images Other images Gold teapot - Gold teapot - Original teapot - Original teapot Rendered teapot - Rendered teapot Real museum - Real museum Stanford bunny images – by Peter Lindstrom et al. well documented at - Stanford bunny images – by Peter Lindstrom et al. well documented at Lena art images – Lena art images – Actual Lena - Actual Lena Lena „pointy“ - Lena „pointy“ Webpages : Webpages : Stanford bunny story - Stanford bunny story The Lena Story - The Lena Story - A Brief History of The Teapot. - A Brief History of The Teapot. - Papers Papers "Zippered Polygon Meshes from Range Images“ - "Zippered Polygon Meshes from Range Images“ -

Famous Images in Computer Graphics & Image Processing Sérgio Leal N.o Erasmus student at: Institute for Computer Graphics and Vision Technical University of Graz