130 research outputs found

    A Simplified 8 × 8 Transformation And Quantization Real-Time Ip-Block For MPEG-4 H.264/AVC Applications: A New Design Flow Approach

    Get PDF
    Current multimedia design processes suffer from the excessively large time spent on testing new IP-blocks with references based on large video encoders specifications (usually several thousands lines of code). The appropriate testing of a single IP-block may require the conversion of the overall encoder from software to hardware, which is difficult to complete in the short time required by the competition-driven reduced time-to-market demanded for the adoption of a new video coding standard. This paper presents a new design flow to accelerate the conformance testing of an IP-block using the H.264/AVC software reference model. An example block of the simplified 8 × 8 transformation and quantization, which is adopted in FRExt, is provided as a case study demonstrating the effectiveness of the approach

    High-Level Synthesis Based VLSI Architectures for Video Coding

    Get PDF
    High Efficiency Video Coding (HEVC) is state-of-the-art video coding standard. Emerging applications like free-viewpoint video, 360degree video, augmented reality, 3D movies etc. require standardized extensions of HEVC. The standardized extensions of HEVC include HEVC Scalable Video Coding (SHVC), HEVC Multiview Video Coding (MV-HEVC), MV-HEVC+ Depth (3D-HEVC) and HEVC Screen Content Coding. 3D-HEVC is used for applications like view synthesis generation, free-viewpoint video. Coding and transmission of depth maps in 3D-HEVC is used for the virtual view synthesis by the algorithms like Depth Image Based Rendering (DIBR). As first step, we performed the profiling of the 3D-HEVC standard. Computational intensive parts of the standard are identified for the efficient hardware implementation. One of the computational intensive part of the 3D-HEVC, HEVC and H.264/AVC is the Interpolation Filtering used for Fractional Motion Estimation (FME). The hardware implementation of the interpolation filtering is carried out using High-Level Synthesis (HLS) tools. Xilinx Vivado Design Suite is used for the HLS implementation of the interpolation filters of HEVC and H.264/AVC. The complexity of the digital systems is greatly increased. High-Level Synthesis is the methodology which offers great benefits such as late architectural or functional changes without time consuming in rewriting of RTL-code, algorithms can be tested and evaluated early in the design cycle and development of accurate models against which the final hardware can be verified

    Efficient reconfigurable architectures for 3D medical image compression

    Get PDF
    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Recently, the more widespread use of three-dimensional (3-D) imaging modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET), and ultrasound (US) have generated a massive amount of volumetric data. These have provided an impetus to the development of other applications, in particular telemedicine and teleradiology. In these fields, medical image compression is important since both efficient storage and transmission of data through high-bandwidth digital communication lines are of crucial importance. Despite their advantages, most 3-D medical imaging algorithms are computationally intensive with matrix transformation as the most fundamental operation involved in the transform-based methods. Therefore, there is a real need for high-performance systems, whilst keeping architectures exible to allow for quick upgradeability with real-time applications. Moreover, in order to obtain efficient solutions for large medical volumes data, an efficient implementation of these operations is of significant importance. Reconfigurable hardware, in the form of field programmable gate arrays (FPGAs) has been proposed as viable system building block in the construction of high-performance systems at an economical price. Consequently, FPGAs seem an ideal candidate to harness and exploit their inherent advantages such as massive parallelism capabilities, multimillion gate counts, and special low-power packages. The key achievements of the work presented in this thesis are summarised as follows. Two architectures for 3-D Haar wavelet transform (HWT) have been proposed based on transpose-based computation and partial reconfiguration suitable for 3-D medical imaging applications. These applications require continuous hardware servicing, and as a result dynamic partial reconfiguration (DPR) has been introduced. Comparative study for both non-partial and partial reconfiguration implementation has shown that DPR offers many advantages and leads to a compelling solution for implementing computationally intensive applications such as 3-D medical image compression. Using DPR, several large systems are mapped to small hardware resources, and the area, power consumption as well as maximum frequency are optimised and improved. Moreover, an FPGA-based architecture of the finite Radon transform (FRAT)with three design strategies has been proposed: direct implementation of pseudo-code with a sequential or pipelined description, and block random access memory (BRAM)- based method. An analysis with various medical imaging modalities has been carried out. Results obtained for image de-noising implementation using FRAT exhibits promising results in reducing Gaussian white noise in medical images. In terms of hardware implementation, promising trade-offs on maximum frequency, throughput and area are also achieved. Furthermore, a novel hardware implementation of 3-D medical image compression system with context-based adaptive variable length coding (CAVLC) has been proposed. An evaluation of the 3-D integer transform (IT) and the discrete wavelet transform (DWT) with lifting scheme (LS) for transform blocks reveal that 3-D IT demonstrates better computational complexity than the 3-D DWT, whilst the 3-D DWT with LS exhibits a lossless compression that is significantly useful for medical image compression. Additionally, an architecture of CAVLC that is capable of compressing high-definition (HD) images in real-time without any buffer between the quantiser and the entropy coder is proposed. Through a judicious parallelisation, promising results have been obtained with limited resources. In summary, this research is tackling the issues of massive 3-D medical volumes data that requires compression as well as hardware implementation to accelerate the slowest operations in the system. Results obtained also reveal a significant achievement in terms of the architecture efficiency and applications performance.Ministry of Higher Education Malaysia (MOHE), Universiti Tun Hussein Onn Malaysia (UTHM) and the British Counci

    MPEG Reconfigurable Video Coding

    Get PDF
    WOS - ISBN: 978-1-4419-6344-4The currentmonolithic and lengthy scheme behind the standardization and the design of new video coding standards is becoming inappropriate to satisfy the dynamism and changing needs of the video coding community. Such a scheme and specification formalism do not enable designers to exploit the clear commonalities between the different codecs, neither at the level of the specification nor at the level of the implementation. Such a problem is one of the main reasons for the typical long time interval elapsing between the time a new idea is validated until it is implemented in consumer products as part of a worldwide standard. The analysis of this problem originated a new standard initiative within the ISO/IEC MPEG committee, called Reconfigurable Video Coding (RVC). The main idea is to develop a video coding standard that overcomes many shortcomings of the current standardization and specification process by updating and progressively incrementing a modular library of components. As the name implies, flexibility and reconfigurability are new attractive features of the RVC standard. The RVC framework is based on the usage of a new actor/dataflow oriented language called CAL for the specification of the standard library and the instantiation of the RVC decoder model. CAL dataflow models expose the intrinsic concurrency of the algorithms by employing the notions of actor programming and dataflow. This chapter gives an overview of the concepts and technologies building the standard RVC framework and the non standard tools supporting the RVC model from the instantiation and simulation of the CAL model to the software and/or hardware code synthesis

    Towards flexible hardware/software encoding using H.264

    Get PDF
    As the electronics world continues to expand, bringing smaller and more portable devices to consumers, demands for media access continue to rise. Consumers are seeking the ability to view the wealth of information available on the Internet from devices such as smart phones, tablets, and music players. In addition to Internet browsing, smart phones and tablets in particular look to reinvent phone communication by adding video chat through services such as Skype and FaceTime. Bringing video to mobile platforms requires trade-offs between size, channel capacity, hardware cost, quality, loading times and power consumption. H.264, the current standard for video encoding specifies multiple profiles to support different modes of operation and environments. Creating an H.264 video encoder for a mobile platform requires a proper balance between the aforementioned trade-offs while maintaining flexibility in a real time environment such as video chatting. The goal of this thesis was to investigate the trade-offs of implementing the H.264 Baseline encoding process specifically at low bit rates in hardware and software using Field Programmable Gate Array (FPGA) reconfigurable resources with an embedded processor core on the same chip. To further preserve encoding flexibility, existing encoding parameters were left intact. The Joint Model (JM) Reference encoder modified to include only the Baseline Profile was used as an initial reference point to evaluate the efficacy of the finished encoder. To improve upon the initial software implementation, major software bottlenecks were identified and hardware accelerators were designed aimed at producing a speedup capable of encoding 176x144 or Quarter Common Intermediate Format (QCIF) videos in real-time at 24 Frames Per Second (FPS) or greater. Finally, the hardware/software implementation was analyzed in comparison with the original JM Reference software encoder. This analysis included FPS, bit rate, encoding time, luminance Peak Signal-to-Noise Ratio (Y-PSNR) and associated hardware costs

    System-on-Chip design of a high performance low power full hardware cabac encoder in H.264/AVC

    Get PDF
    Ph.DDOCTOR OF PHILOSOPH

    A Cost Shared Quantization Algorithm and its Implementation for Multi-Standard Video CODECS

    Get PDF
    The current trend of digital convergence creates the need for the video encoder and decoder system, known as codec in short, that should support multiple video standards on a single platform. In a modern video codec, quantization is a key unit used for video compression. In this thesis, a generalized quantization algorithm and hardware implementation is presented to compute quantized coefficient for six different video codecs including the new developing codec High Efficiency Video Coding (HEVC). HEVC, successor to H.264/MPEG-4 AVC, aims to substantially improve coding efficiency compared to AVC High Profile. The thesis presents a high performance circuit shared architecture that can perform the quantization operation for HEVC, H.264/AVC, AVS, VC-1, MPEG- 2/4 and Motion JPEG (MJPEG). Since HEVC is still in drafting stage, the architecture was designed in such a way that any final changes can be accommodated into the design. The proposed quantizer architecture is completely division free as the division operation is replaced by multiplication, shift and addition operations. The design was implemented on FPGA and later synthesized in CMOS 0.18 μm technology. The results show that the proposed design satisfies the requirement of all codecs with a maximum decoding capability of 60 fps at 187.3 MHz for Xilinx Virtex4 LX60 FPGA of a 1080p HD video. The scheme is also suitable for low-cost implementation in modern multi-codec systems
    corecore