TY - JOUR
T1 - A Spatiotemporal Content-Based CU Size Decision Algorithm for HEVC
AU - Kuo, Yao Tsung
AU - Chen, Pei Yin
AU - Lin, Hong Cheng
N1 - Funding Information:
Manuscript received November 1, 2018; revised February 8, 2019, April 30, 2019, and August 3, 2019; accepted October 16, 2019. Date of publication January 14, 2020; date of current version March 4, 2020. This work was supported in part by the Ministry of Science and Technology at Taiwan, under Contract 105-2221-E-006-157-MY3, and in part by Qualcomm through a Taiwan University Research Collaboration Project. (Corresponding author: Pei-Yin Chen.) The authors are with the Digital Integrated Circuit Design Laboratory, Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 70101, Taiwan (e-mail: [email protected]; [email protected]; [email protected]).
Publisher Copyright:
© 1963-12012 IEEE.
PY - 2020/3
Y1 - 2020/3
N2 - The high efficiency video coding (HEVC) standard provides superior efficiency for encoding and improves the compression ratio by almost 50% compared with previous video coding standards, such as advanced video coding (AVC). However, more intensive computation complexity is introduced by implementing the flexible quad tree-structured coding model. In a typical HEVC encoder, coding units (CUs) in a coding tree unit (CTU) that is built as a quad-tree structure are recursively traversed each depth level (CU size) to select the optimal coding configuration. Therefore, most of the encoding time is spent searching for the optimal coding configuration. In this paper, an efficient and fast CU size decision algorithm is proposed to reduce HEVC encoder complexity by the spatiotemporal features. First, an adaptive depth-range prediction method minimizes the possible range depth level by observing previous frames and proximal CTUs. Second, an early termination method based on the boundary examination from the de-blocking filter (DBF) prevents unnecessary calculation on small CU sizes. Furthermore, according to the sum of absolution difference (SAD), a smooth area detection mechanism is triggered when the predictive depth range excludes the largest CU size. This mechanism increase the bitrate of the CU, which contains static objects with complex textures. Compared with the HM 16, the experimental results revealed that the proposed algorithm can achieve an average 59.73% and 64.98% reduction in encoding time along with a 0.68% and 1.27% Bjontegaard Delta bitrate (BDBR) penalty for various test videos under low-delay P and random-access conditions, respectively.
AB - The high efficiency video coding (HEVC) standard provides superior efficiency for encoding and improves the compression ratio by almost 50% compared with previous video coding standards, such as advanced video coding (AVC). However, more intensive computation complexity is introduced by implementing the flexible quad tree-structured coding model. In a typical HEVC encoder, coding units (CUs) in a coding tree unit (CTU) that is built as a quad-tree structure are recursively traversed each depth level (CU size) to select the optimal coding configuration. Therefore, most of the encoding time is spent searching for the optimal coding configuration. In this paper, an efficient and fast CU size decision algorithm is proposed to reduce HEVC encoder complexity by the spatiotemporal features. First, an adaptive depth-range prediction method minimizes the possible range depth level by observing previous frames and proximal CTUs. Second, an early termination method based on the boundary examination from the de-blocking filter (DBF) prevents unnecessary calculation on small CU sizes. Furthermore, according to the sum of absolution difference (SAD), a smooth area detection mechanism is triggered when the predictive depth range excludes the largest CU size. This mechanism increase the bitrate of the CU, which contains static objects with complex textures. Compared with the HM 16, the experimental results revealed that the proposed algorithm can achieve an average 59.73% and 64.98% reduction in encoding time along with a 0.68% and 1.27% Bjontegaard Delta bitrate (BDBR) penalty for various test videos under low-delay P and random-access conditions, respectively.
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U2 - 10.1109/TBC.2019.2960938
DO - 10.1109/TBC.2019.2960938
M3 - Article
AN - SCOPUS:85081955648
SN - 0018-9316
VL - 66
SP - 100
EP - 112
JO - IEEE Transactions on Broadcasting
JF - IEEE Transactions on Broadcasting
IS - 1
M1 - 8959386
ER -