Lenna (or Lena) is a standard test image used in the field of digital image processing starting in 1973, but it is no longer considered appropriate by some authors. It is a picture of the Swedish model Lena Forsén, shot by photographer Dwight Hooker, cropped from the centerfold of the November 1972 issue of Playboy magazine. The continued use of the image has attracted controversy, on both technical and social grounds, and many journals have discouraged or banned its use. Forsén herself has asked for the image to be retired.

The spelling "Lenna" came from the model's desire to encourage the proper pronunciation of her name. "I didn't want to be called Leena [English: ]," she explained.