Why Video Compression Is Needed - A Practical Guide to Video and Audio Compression - page 27

You may disagree with or feel uncomfortable about this level of surveillance, but it will
likely continue to take place.

2.8.14 Compliance Recording

Broadcasters are required to record their output and store it for 90 days, so that if some-
one wants to complain about something that was said or a rights issue needs to be
resolved, the evidence is there to support or deny the claim. This is called compliance
recording, and historically it was accomplished through a manually operated bank of VHS
recorders running in LP mode and storing 8 hours of video per tape, requiring three cas-
settes per day per channel. The BBC outputs at least six full-frame TV services that need
to be monitored in this way. The archive for 90 days of recording is some 1620 tapes. These
all have to be labeled, cataloged, and stored for easy access in case of a retrieval request.
The TX-2 compliance recorder was built on a Windows platform and was designed
according to the requirements of the regulatory organizations so that UK broadcasters
could store 90 days' worth of content in an automated system. The compliance recorder is
based on a master node with attached slaves, which can handle up to 16 channels in a fly-
configured system. Access to the archived footage is achieved via a Web-based interface,
and the video is then streamed back to the requesting client.
This recorder could not have been built without video compression, and it is a good
example of the kind of product that can be built on top of a platform such as Windows
Media running on a Windows operating system, or other manufacturer's technology.
Because this is a software-based system, the compression ratio and hence the capac-
ity and quality of the video storage can be configured. Less video but at a higher quality
can be stored, or maximal time at low quality. The choice is yours.

2.8.15 Conference Proceedings

Using large-screen displays at conferences is becoming very popular. These are being
driven by a video feed shot by professional camerapeople, and the video is often captured
and made available to delegates after the conference. Siggraph conference proceedings, for
example, make significant use of compression to create the DVD proceedings disk, and the
Apple developer conference proceedings have for some years been a showcase of Apple's
prowess with video workflow and production processes as well as its engineering work
on codecs.

2.8.16 Broadband Video on Demand

During 2004, the BBC tested a system called the Internet Media Player (BBC iMP). This
system presents an electronic program guide (EPG) over a 14-day window. The user
browses the EPG listings and is able to call up something that was missed during the pre-
vious week. Alternatively, a recording can be scheduled during the next few days. In order
to adequately protect the content, the BBC iMP trials are run on a Windows-based plat-
form that supports the Windows Media DRM functionality. If the iMP player were used