In 1972, a photo of a Swedish Playboy model was used to engineer the digital image format that would become the JPEG. The model herself was mostly a mystery—until now. In 1973, a photo of a Swedish Playboy model named Lena (left) was used to engineer the digital image format that would become the JPEG. Yet the model herself (right, now 67) remained mostly a mystery—until now.Original image (L) sho