1. A computer-implemented method for data backup, the method comprising: receiving, at a capturing device, data for backup; creating, at the capturing device, colored cells within a color space to provide an encoded representation of the received data in an image by processing the received data to obtain a stream of integers, each integer in the stream of integers corresponding to a color in the color space for a cell in the image; and creating, at the capturing device, one or more additional cells, including color calibration cells, adjoining the encoded image, the one or more additional cells for assisting in correcting color distortion in the encoded image by determining a pseudo-Euclidean metric in the color space, the metric measuring a distance including a measure of an average of: (a) a red component in the colored cells and (b) a red component in the color calibration cells.