The first time I saw the effect (the unintentional version), I was watching a video on a handheld digital-TV receiver. Historically, this would be an undesirable visual effect because it obviously means an error has occurred with the video compression or video signal. Historically, datamoshing was an undesirable effect, caused by errors with video compression. This results in what we call the datamoshing effect. However, if the d-frames become corrupted, or if the i-frames get removed, the pixels onscreen will move in some extremely glitchy ways.
The d-frames are much more efficient for video compression since they store only pixel movement data rather than an entire image. I-frames are essentially a complete image of a video frame, whereas d-frames are comprised of where pixels from an i-frame need to move to. Compressed videos contain i-frames and d-frames. In short, datamoshing messes with a video’s compression, causing the pixel information to become corrupt.
