Video
When motion prediction is used, as in MPEG-1, MPEG-2 or MPEG-4, compression artifacts tend to remain on several generations of decompressed frames, and move with the optic flow of the image, leading to a peculiar effect, part way between a painting effect and "grime" that moves with objects in the scene.
Data errors in the compressed bit-stream can lead to errors similar to large quantization errors, or can disrupt the parsing of the data stream entirely for a short time, leading to "break-up" of the picture. Where gross errors have occurred in the bit-stream, decoders continue to apply updates to the damaged picture for a short interval, creating a "ghost image" effect, until receiving the next independently compressed frame. In MPEG picture coding, these are known as "I-frames", with the 'I' standing for "intra".
Read more about this topic: Compression Artifact
Famous quotes containing the word video:
“It is among the ranks of school-age children, those six- to twelve-year-olds who once avidly filled their free moments with childhood play, that the greatest change is evident. In the place of traditional, sometimes ancient childhood games that were still popular a generation ago, in the place of fantasy and make- believe play . . . today’s children have substituted television viewing and, most recently, video games.”
—Marie Winn (20th century)
“I recently learned something quite interesting about video games. Many young people have developed incredible hand, eye, and brain coordination in playing these games. The air force believes these kids will be our outstanding pilots should they fly our jets.”
—Ronald Reagan (b. 1911)
“We attempt to remember our collective American childhood, the way it was, but what we often remember is a combination of real past, pieces reshaped by bitterness and love, and, of course, the video past—the portrayals of family life on such television programs as “Leave it to Beaver” and “Father Knows Best” and all the rest.”
—Richard Louv (20th century)