Demystified视频

A popular buzzword has been “convergence”—the intersecTIon of various technologies that were previously unrelated. One of the key elements of mulTImedia convergence in the home and business has been video.A few short years ago, the applicaTIons for video were somewhat confined—analog broadcast and cable television, analog VCRs, analog settop boxes with limited funcTIonality, and simple analog video capture for the personal computer (PC). Since then, there has been a tremendous and rapid conversion to digitalvideo, mostly based on the MPEG and DV (Digital Video) standards.Today we have:• DVD and SuperVCD Players and Recorders. An entire movie can be stored digitally on a single disc. Although earlysystems supported composite and svideo,they rapidly added componentvideo connections for higher video quality.The latest designs already support progressive scan capability, pushing thevideo quality level even higher.• Digital VCRs and Camcorders. DVCRs that store digital audio and video on tapeare now common.Many include an IEEE 1394 interface to allow the transferof audio and video digitally in order to maintain the high quality video andaudio.• Digital Settop Boxes. These interface the television to the digital cable, satellite,or broadcast system. In addition, many now also provide support for interactivity, datacasting, sophisticated graphics,and internet access. Many will include DVI and IEEE 1394 interfaces to allow the transfer of audio, video, and data digitally.• Digital Televisions (DTV). These receive and display digital televisionbroadcasts, either via cable, satellite, or over-the-air. Both standard-definition(SDTV) and high-definition (HDTV) versions are available.