The team designed its system so that snippets of DNA corresponded to pixels in an image. The researchers encoded the shading of each pixel along with a barcode that indicated its position in the image into 33 DNA letters. Each frame of the movie consisted of 104 of these DNA fragments.
The DNA was introduced into E. coli bacteria at a rate of one frame per day for five days. The researchers then sequenced the CRISPR regions in a population of bacteria to recover the image. Because the CRISPR system adds DNA snippets sequentially, the position of each snippet in the array could be used to determine the original frame to which the snippet belonged.
Being able to store information (other than genetic) in DNA is kinda crazy!