Lenna 97: A Complete Story of Lenna


Introduction

Lenna Picture

Engineers, researchers, and students who are familiar with image processing or compression has most likely used the picture of "Lenna" or "Lena" in their experiments or project assignments, as the Lenna picture is one of the most widely used standard test images. Today, the use of Lenna image has been recognized as one of the most important events in the history of electronic imaging. However, very few people have seen the original picture and know the complete story of Lenna. Here is the materials about Lenna I have recently found on the Internet, which includes the recent picture of Lenna in May 1997.

Who is "Lenna" or "Lena"?

From the comp.compression FAQ, we can find that "Lenna" or "Lena" is a digitized Playboy centerfold, from November 1972. Lenna is the spelling in Playboy, Lena is the Swedish spelling of her name. (In English, Lena is sometimes spelled Lenna, to encourage proper pronounciation.) Lena Soderberg (ne Sjooblom) was last reported living in her native Sweden, happily married with three kids and a job with the state liquor monopoly. In 1988, she was interviewed by some Swedish computer related publication, and she was pleasantly amused by what had happened to her picture. That was the first she knew of the use of that picture in the computer business.

When and where the Lenna picture creates?

In the Playboy and Wired News, we know that in the early Seventies Lenna's Playboy centerfold was scanned in by an unknown researcher at the University of Southern California to use as a test image for digital image compression research. Since that time, images of the Playmate have been used as the industry standard for testing ways in which pictures can be manipulated and transmitted electronically. Over the past 25 years, no image has been more important in the history of imaging and electronic communications, and today the mysterious Lenna is considered the First Lady of the Internet.

Why using the "Lenna" image?

Two reason was stated in "A Note on Lena" by David C. Munson. First, the Lenna image contains a nice mixture of detail, flat regions, shading, and texture that do a good job of testing various image processing algorithms. It is a good test image! Second, the Lena image is a picture of an attractive woman. It is not surprising that the (mostly male) image processing research community gravitated toward an image that they found attractive.

Who create the "Lenna" image?

In October 29, 1999, I received an email from Chuck McNanis telling us that the "unknown researcher" who scanned the "Lenna" image was Dr. William K. Pratt. Here is the email:

I worked for 5 years ('78 - '83) at the Image Processing Institute as a system programmer in the Image Processing Lab (IPL) which distributed Lenna and several other images (including the Mandril) which people often refer to as "The baboon image." The "unknown researcher" was Dr. William K. Pratt, now of Sun Microsystems, who was writing a book on image processing and he needed some standard images for it. For a long time the folded up centerfold that had been the basis for that image was in the file cabinet at the lab. I went back in 1997 to visit and the lab has undergone many changes and the original image files were nowhere to be found. The original distribution format was 1600BPI 9-track tape with each color plane stored separately.

--Chuck McManis (USC Class of '83)

Want to see the original Lenna?

The standard digital Lenna image is just a closeup of the original picture with her face and bare shoulder. Recently, Chuck Rosenberg obtained a copy of the original Playboy Magazine and put it on the Internet. Here's a glimpse:

[Original Lena Image]

Click here to see the Origional Playboy Picture (Caution....Contains Nudity)
The full picture can also be found in the Chuck's site or www.lenna.org.

Want to see the Lenna in 1997?

No problem! Lenna was invited to attend the 50th Anniversary IS&T conference in Boston on May 1997. With the assistance of Playboy, Jeff Seideman (the president of the Boston chapter of the IS&T) arranged Lenna to appear at the IS&T Boston, as part of an overview of the history of digital imaging.

Here is a picture of Lenna taken in May 1997 at the IS&T's conference:

[Picture of Lenna at IS&T]

At the conference, she was busy signing autographs, posing for pictures, and giving a presentation about herself. Lenna commented to the Wired reporter: "They must be so tired of me ... looking at the same picture for all these years!"

Currently, Lenna lives near Stockholm and works for a government agency supervising handicapped employees archiving data using, appropriately, computers and scanners.

Where can I find the standard Lenna picture?

The standard version of Lenna is also available on a lot of ftp sites, detail can be found in the comp.compression FAQ. In addition, you can also obtain the Lenna image from the Miscellaneous volume of the USC-SIPI image database, which costs $100 for distribution on 8mm or 4mm tape. The ordering details can be found in Signal and Image Processing Institute of the University of Southern California.

We may have a new standard Lenna image?

As mentioned by Seideman in Playboy Newsdesk, over the years some researchers have complained that they lacked vital information about the Lenna image, such as what type of scanner was originally used, what kind of camera and film. He says that he is working with Playboy's archivist to re-scan Lenna's image and compile all the missing information, including everything from the type of photo emulsion used to make the print to the technical specifications of the scanner. In this way, Seideman says, the image of this Playboy Playmate can remain the standard reference image for comparing compression technologies into the 21st century.

Where can I find compression research using Lenna?

If you are a student, you may be interested in doing image compression research after knowing the Lenna story. In the nineties, wavelet is one of the hottest topics in image compression research. A very good web page that listed the results of the most recent wavelet image coding techniques using Lenna as the test image is published in Image Communication Lab of UCLA. In the SPIHT (Set Partitioning in Hierarchical Trees) site, demonstration images and software are provided for the Said & Pearlman algorithm. This is one of the most impressive image compression algorithms in terms of performance/bit rate/complexity tradeoffs. A Lenna Results Page is also availalbe on the Internet, which consists of reconstructed images using adaptive wavelet coder and JPEG. To start your research, the wavelet image compression construction kit could help you a lot, which contains images, wavelet transform code, filter coefficients, and lots of other resources for wavelet compression. For more wavelet coding related sites, you can find on the Signal Processing and the Multimedia Information Infrastructure. Finally, we are sure that after the discovering of the complete Lenna story, we will enjoy our research more with the lovely Lenna picture.


Lai-Man Po
First version: July 28, 1997
Second version: Nov. 4, 1999
Last update: Feb. 21, 2001