Graphics Reference
In-Depth Information
3.1 2DVideo Coding
The primary aim of video coding is the removal of spatial and temporal redundancies
presentinrawimagescapturedfromavideocamera.Videocodingallowsvideotobeused
in communication applications with reduced storage and bitrate requirements. The block-
based transform coding and subband-based decomposition of images are commonly util-
ized as the basic coding principles. Video coding has been standardized (H.261 in 1990,
MPEG-1 Video in 1993, MPEG-2 Video in 1994, H.263 in 1997, MPEG-4 Visual or
part 2 in 1998, H.264/AVC in 2004, HEVC in 2013), in order to facilitate the interop-
erabilityamongdifferentproductsandapplications.Thetechnologyadvancesresultinhigh-
er compression efficiency, different application support (video telephony-H.261, consumer
video on CD- MPEG-1, broadcast of Standard Definition: SD/High Definition: HD TV-
MPEG-2 and 4K/8K TV: HEVC) and network compliance (switched networks such as
PSTN- H.263/MPEG-4 or ISDN- H.261 and Internet or mobile networks H.263/H.264/
MPEG-4).Mostofthevideocodingstandardsarebasedonhybridvideocodingwhichem-
ploysblockmatching(i.e.BlockMatchingAlgorithm:BMA)motioncompensationandthe
DiscreteCosineTransform(DCT).Thereasonsforadoptinghybridvideocodingapproach
are that:
• A significant proportion of the motion trajectories found in natural
video can be approximately described with a rigid translational motion
model.
• Fewer bits are required to describe simple translational motion.
• Implementation is relatively straightforward and amenable to hardware
solutions.
