46 research outputs found
A highly efficient multiplication-free binary arithmetic coder and its application in video coding. In: ICIP
ABSTRACT INTRODUCTION Arithmetic coding has attracted a growing attention in the past years. Recently developed image coding standards like JBIG-2, JPEG-LS or JPEG2000 Binary arithmetic coding is based on the principle of recursive interval subdivision that involves the following elementary multiplication operation. Suppose that an estimate of the probability p LPS of the least probable symbol (LPS) is given and that the given coding interval is represented by its lower bound (base) L and its width (range) R. Based on that settings, the given interval is subdivided into two sub-intervals: one interval of width R LPS = R × p LPS
Region-Based Template Matching Prediction for Intra Coding
Copy prediction is a renowned category of prediction techniques in video coding where the current block is predicted by copying the samples from a similar block that is present somewhere in the already decoded stream of samples. Motion-compensated prediction, intra block copy, template matching prediction etc. are examples. While the displacement information of the similar block is transmitted to the decoder in the bit-stream in the first two approaches, it is derived at the decoder in the last one by repeating the same search algorithm which was carried out at the encoder. Region-based template matching is a recently developed prediction algorithm that is an advanced form of standard template matching. In this method, the reference area is partitioned into multiple regions and the region to be searched for the similar block(s) is conveyed to the decoder in the bit-stream. Further, its final prediction signal is a linear combination of already decoded similar blocks from the given region. It was demonstrated in previous publications that region-based template matching is capable of achieving coding efficiency improvements for intra as well as inter-picture coding with considerably less decoder complexity than conventional template matching. In this paper, a theoretical justification for region-based template matching prediction subject to experimental data is presented. Additionally, the test results of the aforementioned method on the latest H.266/Versatile Video Coding (VVC) test model (version VTM-14.0) yield an average Bjøntegaard-Delta (BD) bit-rate savings of −0.75% using all intra (AI) configuration with 130% encoder run-time and 104% decoder run-time for a particular parameter selection
HEVC performance and complexity for 4K video
The recently finalized High-Efficiency Video Coding (HEVC) standard was jointly developed by the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG) to improve the compression performance of current video coding standards by 50%. Especially when it comes to transmit high resolution video like 4K over the internet or in broadcast, the 50% bitrate reduction is essential. This paper shows that real-time decoding of 4K video with a frame-level parallel decoding approach using four desktop CPU cores is feasible
DeepCABAC: A Universal Compression Algorithm for Deep Neural Networks
The field of video compression has developed some of the most sophisticated
and efficient compression algorithms known in the literature, enabling very
high compressibility for little loss of information. Whilst some of these
techniques are domain specific, many of their underlying principles are
universal in that they can be adapted and applied for compressing different
types of data. In this work we present DeepCABAC, a compression algorithm for
deep neural networks that is based on one of the state-of-the-art video coding
techniques. Concretely, it applies a Context-based Adaptive Binary Arithmetic
Coder (CABAC) to the network's parameters, which was originally designed for
the H.264/AVC video coding standard and became the state-of-the-art for
lossless compression. Moreover, DeepCABAC employs a novel quantization scheme
that minimizes the rate-distortion function while simultaneously taking the
impact of quantization onto the accuracy of the network into account.
Experimental results show that DeepCABAC consistently attains higher
compression rates than previously proposed coding techniques for neural network
compression. For instance, it is able to compress the VGG16 ImageNet model by
x63.6 with no loss of accuracy, thus being able to represent the entire network
with merely 8.7MB. The source code for encoding and decoding can be found at
https://github.com/fraunhoferhhi/DeepCABAC
Entropy Coding in HEVC
Context-Based Adaptive Binary Arithmetic Coding (CABAC) is a method of entropy coding first introduced in H.264/AVC and now used in the latest High Efficiency Video Coding (HEVC) standard. While it provides high coding efficiency, the data dependencies in H.264/AVC CABAC make it challenging to parallelize and thus limit its throughput. Accordingly, during the standardization of entropy coding for HEVC, both aspects of coding efficiency and throughput were considered. This chapter describes the functionality and design methodology behind CABAC entropy coding in HEVC
Overview of the scalable H.264/MPEG4-AVC extension
The scalable extension of H.264/MPEG4-AVC is a current standardization project of the Joint Video Team (JVT) of the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG). This paper gives an overview of the design of the scalable H.264/MPEG4-AVC extension and describes the basic concepts for supporting temporal, spatial, and SNR scalability. The efficiency of the described concepts for providing spatial and SNR scalability is analyzed by means of simulation results and compared to H.264/MPEG4-AVC compliant single layer coding
SNR-scalable Extension . . .
This document contains a description of an SNR-scalable extension of H.264/AVC [1]. To achieve an efficient SNR-scalable bitstream representation of a video sequence, the temporal dependency between pictures is coded using an open-loop subband approach. In this codec, most components of H.264/AVC are used as specified in the standard while only a few have been adjusted to the subband coding structure. We have tested a first version of the approach with QCIF and CIF resolution sequences obtaining some promising results