Graphics Reference
In-Depth Information
Tabl e 8. 20
Summary of throughput improvement techniques with references to related standard
contributions
Technique
PU coding
TU coding
Reduce regular coded bins
[
58
]
[
16
,
54
,
59
]
Group bypass bins
[
19
,
67
]
[
87
]
Group bins with same context
[
58
]
[
9
,
10
,
73
]
Reduce context modeling dependencies
[
18
,
80
,
85
,
86
]
Reduce total number of bins
[
12
,
56
]
Reduce memory requirements
[
58
,
82
,
90
,
91
]
[
3
,
15
,
20
,
62
,
66
,
81
,
82
,
93
,
99
]
Reduce parsing dependencies
[
107
,
108
]
8.8.2.5
Reduce Total Number of Bins
When comparing the total number of bins in the worst case, and thus the throughput
requirement, HEVC has 1:5
fewer bins than H.264/AVC. Assuming the same
number of cycles per bin are required, HEVC can run at a 1:5
lower clock rate
at a lower voltage for 50 % power savings assuming linear scaling with voltage and
frequency, or it can process at a bin rate that is 1:5
faster than H.264/AVC.
8.8.2.6
Reduce Parsing Dependencies
Parsing dependencies were removed or reduced such that coding gains could
be achieve without significantly sacrificing throughput. Removing the parsing
dependency for merge and mvp enables parsing to be mostly decoupled from the
reconstruction process, as it is the case for H.264/AVC. HEVC does have parsing
dependencies on intra mode reconstruction, which are not present in H.264/AVC;
however, efforts were made to keep intra mode reconstruction simple to avoid
affecting parsing throughput.
8.8.2.7
Summary of Throughput Improvement Techniques
Tab le
8.20
contains a summary of the techniques for throughput improvement and
related standard contributions. An HEVC CABAC decoder that leverages several of
these improvements to achieve a throughput of over 2 Gbin/s is described in [
17
].
8.8.3
Memory Requirement Reduction
This section describes how the size and bandwidth requirements of various memo-
ries in CABAC have been reduced in HEVC in order to increase throughput as well
as lower implementation cost and power consumption.
