The World of Digital Video
J.F. Blinn, Cal Tech
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Discusses some elements of the transition from "thinking analog" to
"thinking digital" for continuous video, and compares how
synchronization and quantization are done for the domininant composite
and component DV standards.
Interestingly, these standards comprise a fair amount of
"analog stuff" like blanking periods. To my mind, there should be
no unused regions in a DV stream: they should be compacted out to
reduce bandwidth, and the receiver should compute the
appropriate blanking as the stream is sent to display hardware.
- Image represented as stream of encoded bytes, rather than an
explicit time-varying YIQ wave; issues related to byte framing
and stream synchronization
- SMPTE 244M standard for composite digital video, and SMPTE
RP125/CCIR601/4:2:2 standard for component video
- Use of quantization to adapt byte values to the existing "IRE
- Embedding of other auxiliary data in unused regions of byte streams
Relevance to Multimedia
Like all standards, not particularly fascinating reading but good to
3 out of 5: a good explanation of a less-than-thrilling topic.
Armando Fox (firstname.lastname@example.org)