Low energy HEVC video compression hardware designs

Joint collaborative team on video coding (JCT-VC) recently developed a new international video compression standard called High Efficiency Video Coding (HEVC). HEVC has 37% better compression efficiency than H.264 which is the current state-of-the-art video compression standard. HEVC achieves this video compression efficiency by significantly increasing the computational complexity. Therefore, in this thesis, we propose novel computational complexity and energy reduction techniques for intra prediction algorithm used in HEVC video encoder and decoder. We quantified the computation reductions achieved by these techniques using HEVC HM reference software encoder. We designed efficient hardware architectures for these video compression algorithms used in HEVC. We also designed a reconfigurable sub-pixel interpolation hardware for both HEVC encoder and decoder. We implemented these hardware architectures in Verilog HDL. We mapped the Verilog RTL codes to a Xilinx Virtex 6 FPGA and estimated their power consumptions on this FPGA using Xilinx XPower Analyzer tool. The proposed techniques significantly reduced the energy consumptions of these FPGA implementations in some cases with no PSNR loss and in some cases with very small PSNR loss

Low energy video processing and compression hardware designs

Digital video processing and compression algorithms are used in many commercial products such as mobile devices, unmanned aerial vehicles, and autonomous cars. Increasing resolution of videos used in these commercial products increased computational complexities of digital video processing and compression algorithms. Therefore, it is necessary to reduce computational complexities of digital video processing and compression algorithms, and energy consumptions of digital video processing and compression hardware without reducing visual quality. In this thesis, we propose a novel adaptive 2D digital image processing algorithm for 2D median filter, Gaussian blur and image sharpening. We designed low energy 2D median filter, Gaussian blur and image sharpening hardware using the proposed algorithm. We propose approximate HEVC intra prediction and HEVC fractional interpolation algorithms. We designed low energy approximate HEVC intra prediction and HEVC fractional interpolation hardware. We also propose several HEVC fractional interpolation hardware architectures. We propose novel computational complexity and energy reduction techniques for HEVC DCT and inverse DCT/DST. We designed high performance and low energy hardware for HEVC DCT and inverse DCT/DST including the proposed techniques. VII We quantified computation reductions achieved and video quality loss caused by the proposed algorithms and techniques. We implemented the proposed hardware architectures in Verilog HDL. We mapped the Verilog RTL codes to Xilinx Virtex 6 and Xilinx ZYNQ FPGAs, and estimated their power consumptions using Xilinx XPower Analyzer tool. The proposed algorithms and techniques significantly reduced the power and energy consumptions of these FPGA implementations in some cases with no PSNR loss and in some cases with very small PSNR loss

An efficient FPGA implementation of versatile video coding intra prediction

Versatile Video Coding (VVC) is a new international video compression standard offering much better compression efficiency than previous video compression standards at the expense of much higher computational complexity. In this paper, an efficient FPGA implementation of VVC intra prediction for angular prediction modes of 4x4, 8x8, 16x16 and 32x32 prediction unit sizes is proposed. In the proposed FPGA implementation, four constant multiplications used in one intra angular prediction equation are implemented using two DSP blocks and two adders in FPGA. The proposed FPGA implementation of VVC intra prediction, in the worst case, can process 34 full HD (1920x1080) frames per second

FPGA implementation of HEVC intra prediction using high-level synthesis

Intra prediction algorithm in the recently developed High Efficiency Video Coding (HEVC) standard has very high computational complexity. High-level synthesis (HLS) tools are started to be successfully used for FPGA implementations of digital signal processing algorithms. Therefore, in this paper, the first FPGA implementation of HEVC intra prediction algorithm using a HLS tool in the literature is proposed. The proposed HEVC intra prediction hardware, in the worst case, can process 35 full HD (1920×1080) video frames per second. Using HLS tool significantly reduced the FPGA development time. Therefore, HLS tools can be used for FPGA implementation of HEVC video encoder

Novel approximate absolute difference hardware

Approximate hardware designs have higher performance, smaller area or lower power consumption than exact hardware designs at the expense of lower accuracy. Absolute difference (AD) operation is heavily used in many applications such as motion estimation (ME) for video compression, ME for frame rate conversion, stereo matching for depth estimation. Since most of the applications using AD operation are error tolerant by their nature, approximate hardware designs can be used in these applications. In this paper, novel approximate AD hardware designs are proposed. The proposed approximate AD hardware implementations have higher performance, smaller area and lower power consumption than exact AD hardware implementations at the expense of lower accuracy. They also have less error, smaller area and lower power consumption than the approximate AD hardware implementations which use approximate adders proposed in the literature

FPGA implementations of HEVC sub-pixel interpolation using high-level synthesis

Sub-pixel interpolation is one of the most computationally intensive parts of High Efficiency Video Coding (HEVC) video encoder and decoder. High-level synthesis (HLS) tools are started to be successfully used for FPGA implementations of digital signal processing algorithms. Therefore, in this paper, the first FPGA implementation of HEVC sub-pixel (half-pixel and quarter-pixel) interpolation algorithm using a HLS tool in the literature is proposed. The proposed HEVC sub-pixel interpolation hardware is implemented on Xilinx FPGAs using Xilinx Vivado HLS tool. It, in the worst case, can process 45 quad full HD (3840×2160) video frames per second. Using HLS tool significantly reduced the FPGA development time. Therefore, HLS tools can be used for FPGA implementation of HEVC video encoder

Low complexity HEVC sub-pixel motion estimation technique and its hardware implementation

In this paper, a low complexity High Efficiency Video Coding (HEVC) sub-pixel motion estimation (SPME) technique is proposed. The proposed technique reduces the computational complexity of HEVC SPME significantly at the expense of slight quality loss by calculating the sum of absolute difference (SAD) values of sub-pixel search locations using the SAD values of neighboring integer pixel search locations. In this paper, an efficient HEVC SPME hardware implementing the proposed technique for all prediction unit (PU) sizes is also designed and implemented using Verilog HDL. The proposed hardware, in the worst case, can process 38 Quad Full HD (3840×2160) video frames per second