544 research outputs found
DyPS: Dynamic Processor Switching for Energy-Aware Video Decoding on Multi-core SoCs
In addition to General Purpose Processors (GPP), Multicore SoCs equipping
modern mobile devices contain specialized Digital Signal Processor designed
with the aim to provide better performance and low energy consumption
properties. However, the experimental measurements we have achieved revealed
that system overhead, in case of DSP video decoding, causes drastic
performances drop and energy efficiency as compared to the GPP decoding. This
paper describes DyPS, a new approach for energy-aware processor switching (GPP
or DSP) according to the video quality . We show the pertinence of our solution
in the context of adaptive video decoding and describe an implementation on an
embedded Linux operating system with the help of the GStreamer framework. A
simple case study showed that DyPS achieves 30% energy saving while sustaining
the decoding performanc
Joint Algorithm-Architecture Optimization of CABAC
This paper uses joint algorithm and architecture design to enable high coding efficiency in conjunction with high processing speed and low area cost. Specifically, it presents several optimizations that can be performed on Context Adaptive Binary Arithmetic Coding (CABAC), a form of entropy coding used in H.264/AVC, to achieve the throughput necessary for real-time low power high definition video coding. The combination of syntax element partitions and interleaved entropy slices, referred to as Massively Parallel CABAC, increases the number of binary symbols that can be processed in a cycle. Subinterval reordering is used to reduce the cycle time required to process each binary symbol. Under common conditions using the JM12.0 software, the Massively Parallel CABAC, increases the bins per cycle by 2.7 to 32.8× at a cost of 0.25 to 6.84% coding loss compared with sequential single slice H.264/AVC CABAC. It also provides a 2× reduction in area cost, and reduces memory bandwidth. Subinterval reordering reduces the critical path delay by 14 to 22%, while modifications to context selection reduces the memory requirement by 67%. This work demonstrates that accounting for implementation cost during video coding algorithms design can enable higher processing speed and reduce hardware cost, while still delivering high coding efficiency in the next generation video coding standard.Texas Instruments Incorporated (Graduate Women's Fellowship for Leadership in Microelectronics)Natural Sciences and Engineering Research Council of Canad
A 249-Mpixel/s HEVC Video-Decoder Chip for 4K Ultra-HD Applications
High Efficiency Video Coding, the latest video standard, uses larger and variable-sized coding units and longer interpolation filters than [H.264 over AVC] to better exploit redundancy in video signals. These algorithmic techniques enable a 50% decrease in bitrate at the cost of computational complexity, external memory bandwidth, and, for ASIC implementations, on-chip SRAM of the video codec. This paper describes architectural optimizations for an HEVC video decoder chip. The chip uses a two-stage subpipelining scheme to reduce on-chip SRAM by 56 kbytes-a 32% reduction. A high-throughput read-only cache combined with DRAM-latency-aware memory mapping reduces DRAM bandwidth by 67%. The chip is built for HEVC Working Draft 4 Low Complexity configuration and occupies 1.77 mm[superscript 2] in 40-nm CMOS. It performs 4K Ultra HD 30-fps video decoding at 200 MHz while consuming 1.19 [nJ over pixel] of normalized system power.Texas Instruments Incorporate
A Deeply Pipelined CABAC Decoder for HEVC Supporting Level 6.2 High-tier Applications
High Efficiency Video Coding (HEVC) is the latest video coding standard that specifies video resolutions up to 8K Ultra-HD (UHD) at 120 fps to support the next decade of video applications. This results in high-throughput requirements for the context adaptive binary arithmetic coding (CABAC) entropy decoder, which was already a well-known bottleneck in H.264/AVC. To address the throughput challenges, several modifications were made to CABAC during the standardization of HEVC. This work leverages these improvements in the design of a high-throughput HEVC CABAC decoder. It also supports the high-level parallel processing tools introduced by HEVC, including tile and wavefront parallel processing. The proposed design uses a deeply pipelined architecture to achieve a high clock rate. Additional techniques such as the state prefetch logic, latched-based context memory, and separate finite state machines are applied to minimize stall cycles, while multibypass- bin decoding is used to further increase the throughput. The design is implemented in an IBM 45nm SOI process. After place-and-route, its operating frequency reaches 1.6 GHz. The corresponding throughputs achieve up to 1696 and 2314 Mbin/s under common and theoretical worst-case test conditions, respectively. The results show that the design is sufficient to decode in real-time high-tier video bitstreams at level 6.2 (8K UHD at 120 fps), or main-tier bitstreams at level 5.1 (4K UHD at 60 fps) for applications requiring sub-frame latency, such as video conferencing
A Survey on Energy Consumption and Environmental Impact of Video Streaming
Climate change challenges require a notable decrease in worldwide greenhouse
gas (GHG) emissions across technology sectors. Digital technologies, especially
video streaming, accounting for most Internet traffic, make no exception. Video
streaming demand increases with remote working, multimedia communication
services (e.g., WhatsApp, Skype), video streaming content (e.g., YouTube,
Netflix), video resolution (4K/8K, 50 fps/60 fps), and multi-view video, making
energy consumption and environmental footprint critical. This survey
contributes to a better understanding of sustainable and efficient video
streaming technologies by providing insights into the state-of-the-art and
potential future directions for researchers, developers, and engineers, service
providers, hosting platforms, and consumers. We widen this survey's focus on
content provisioning and content consumption based on the observation that
continuously active network equipment underneath video streaming consumes
substantial energy independent of the transmitted data type. We propose a
taxonomy of factors that affect the energy consumption in video streaming, such
as encoding schemes, resource requirements, storage, content retrieval,
decoding, and display. We identify notable weaknesses in video streaming that
require further research for improved energy efficiency: (1) fixed bitrate
ladders in HTTP live streaming; (2) inefficient hardware utilization of
existing video players; (3) lack of comprehensive open energy measurement
dataset covering various device types and coding parameters for reproducible
research
Motion estimation and CABAC VLSI co-processors for real-time high-quality H.264/AVC video coding
Real-time and high-quality video coding is gaining a wide interest in the research and industrial community for different applications. H.264/AVC, a recent standard for high performance video coding, can be successfully exploited in several scenarios including digital video broadcasting, high-definition TV and DVD-based systems, which require to sustain up to tens of Mbits/s. To that purpose this paper proposes optimized architectures for H.264/AVC most critical tasks, Motion estimation and context adaptive binary arithmetic coding. Post synthesis results on sub-micron CMOS standard-cells technologies show that the proposed architectures can actually process in real-time 720 × 480 video sequences at 30 frames/s and grant more than 50 Mbits/s. The achieved circuit complexity and power consumption budgets are suitable for their integration in complex VLSI multimedia systems based either on AHB bus centric on-chip communication system or on novel Network-on-Chip (NoC) infrastructures for MPSoC (Multi-Processor System on Chip
CABAC accelerator architectures for video compression in future multimedida : a survey
The demands for high quality, real-time performance and multi-format video support in consumer multimedia products are ever increasing. In particular, the future multimedia systems require efficient video coding algorithms and corresponding adaptive high-performance computational platforms. The H.264/AVC video coding algorithms provide high enough compression efficiency to be utilized in these systems, and multimedia processors are able to provide the required adaptability, but the algorithms complexity demands for more efficient computing platforms. Heterogeneous (re-)configurable systems composed of multimedia processors and hardware accelerators constitute the main part of such platforms. In this paper, we survey the hardware accelerator architectures for Context-based Adaptive Binary Arithmetic Coding (CABAC) of Main and High profiles of H.264/AVC. The purpose of the survey is to deliver a critical insight in the proposed solutions, and this way facilitate further research on accelerator architectures, architecture development methods and supporting EDA tools. The architectures are analyzed, classified and compared based on the core hardware acceleration concepts, algorithmic characteristics, video resolution support and performance parameters, and some promising design directions are discussed. The comparative analysis shows that the parallel pipeline accelerator architecture seems to be the most promising
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