After a decade of development and standardization efforts,
digital video is now poised to take over broadcast television.
With this transition, some digital video processor ICs are moving
toward commodity status while others embrace innovation
and diversification. The result of this shift is a growing range of
product offerings as well as an open door to a host of new video
applications.
General-purpose DSPs from companies like Analog Devices
and Texas Instruments dominated the early years of digital
video processing. Rapid evolution in video-compression technology
as well as contending standards made designers seek
the flexibility of a programmable solution while discouraging
the development of specialized hardware.
With the stabilization of standards like H.264, MPEG-2,
and MPEG-4 as well as the Federal Communications Commission
mandate for conversion to digital broadcast television
by 2009, specialized ICs became more cost-effective to develop
and apply. Digital video processors then began to appear.
This sounds like the same pathway that many technologies
follow: processor to hardware to commodity. But once digital
video technology began to stabilize, it took a different path, or
rather, many different paths.
Digital video began branching out beyond television into
an array of application areas, engendering a growing variety of
processing options. These range from video-augmented DSPs
all the way to dedicated-function processors and coprocessors. A
significant amount of intellectual property for system-on-a-chip
(SoC) and FPGA design is available as well (see “Digital Video
Processing IP,” p. 46).
A handful of application areas currently dominates the
digital video processor market. The consumer broadcast digital
television receiver market, naturally, is one of the largest in
terms of volume. Commercial television, personal video, and
video conferencing, all utilizing the Internet Protocol (IP)
as the delivery mechanism, represent another major market.
Other significant markets include equipment for studios, content
providers, and video-based surveillance.
DIVERSITY BREEDS CHALLENGES
Each of these application areas poses a different challenge for
equipment developers as well as their processor vendors. Studio
equipment along with both broadcast and network-based
digital television receivers need high-performance, standardsbased
processing at low cost. Surveillance applications also require high performance, but are more concerned with applications
flexibility than with standards.
The IP-based handheld video market is somewhat less concerned
with performance, due to lower expectations for video quality,
but it’s acutely interested in low power. The communications
part of this market is also focused on minimizing latency.
This range of applications and design requirements has produced
a continual stream of new digital video processor introductions
that shows no sign of abating. The consumer broadcast and
network-based digital television receiver markets, in particular, are
awash with processor introductions from companies like Freescale
Semiconductor, Sigma Designs, STMicroelectronics, Texas
Instruments, and Toshiba.
These companies seek to offer developers options that allow
tradeoffs between high performance and low cost for different
market segments. They also offer tradeoffs between highly
specialized fixed and more flexible programmable digital video
processing.
The highly targeted STMicroelectronics STi7111 set-top-box
(STB) decoder chip combines a CPU for applications processing;
decoders for H.264, MPEG-2, and VC1 data streams; and
demodulators for satellite television signals. It also offers an Ethernet
port for receiving video over IP networks.
Similarly, the SMP8564 STB decoder from Sigma Designs
incorporates multiple processors, video-enhancement hardware
accelerators, and audio subsystems on chip to handle all essential
functions of an STB design (Fig. 1).
Such high integration is common for processors in the broadcast
television market. The Toshiba TC90413XBG packs virtually
all of the processing needed for a digital television receiver into
one chip (Fig. 2). It needs only an audio amplifier, an LCD panel,
and some memory as additional active components.
But along with such targeted devices, vendors offer many
degrees of programmability as options. According to Gerard
Andrews, applications processor product line manager at Texas
Instruments, such offerings seek to address a wide range of applications
beyond consumer video.
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