  The latest High Efficiency Video Coding (HEVC) standard significantly
improves coding efficiency over its previous video coding standards. The
expense of such improvement is enormous computational complexity, from both
encoding and decoding sides. Since computational capability and power capacity
are diverse across portable devices, it is necessary to reduce decoding
complexity to a target with tolerable quality loss, so called complexity
control. This paper proposes a Saliency-Guided Complexity Control (SGCC)
approach for HEVC decoding, which reduces the decoding complexity to the target
with minimal perceptual quality loss. First, we establish the SGCC formulation
to minimize perceptual quality loss at the constraint on reduced decoding
complexity, which is achieved via disabling Deblocking Filter (DF) and
simplifying Motion Compensation (MC) of some non-salient Coding Tree Units
(CTUs). One important component in this formulation is the modelled
relationship between decoding complexity reduction and DF disabling/MC
simplification, which determines the control accuracy of our approach. Another
component is the modelled relationship between quality loss and DF disabling/MC
simplification, responsible for optimizing perceptual quality. By solving the
SGCC formulation for a given target complexity, we can obtain the DF and MC
settings of each CTU, and then decoding complexity can be reduced to the
target. Finally, the experimental results validate the effectiveness of our
SGCC approach, from the aspects of control performance, complexity-distortion
performance, fluctuation of quality loss and subjective quality.
