Dirac Video Codec

2011 ◽  
pp. 58-94
Author(s):  
Kok Keong ◽  
Myo Tun ◽  
Yoong Choon Chang
Keyword(s):  
Video Coding ◽  
Data Storage ◽  
Video Compression ◽  
Rate Distortion ◽  
Video Codec ◽  
Discrete Wavelet ◽  
Coding System ◽  
Web Content ◽  
Video Codecs ◽  
Block Based

Dirac was started off by British Broadcasting Corp. (BBC) in 2003 as an experimental video coding system based on wavelet technology, which is different from that used in the main proprietary/standard video compression systems. Over the years, Dirac has grown out of its initial development and it is now on offer as an advanced royalty-free video coding system designed for a wide range of users, from delivering low-resolution web content to broadcasting high-definition (HD) and beyond, to near-lossless studio editing. The Dirac’s video coding architecture and algorithms are designed with the “keep it simple” mindset. In spite of that the Dirac seems to give a two-fold reduction in bitrate over MPEG-2 for HD video and broadly competitive with state-of-the-art video codecs. This chapter introduces the architecture of Dirac video encoder. The overall encoding structure is discussed followed by the detail description of motion estimation, Overlapped Block-based Motion Compensation (OBMC), Discrete Wavelet Transform (DWT), Rate Distortion Optimization (RDO) quantization and entropy coding. The Dirac’s bitstream syntax for compressed video data storage and streaming is described. Besides that, the coding performance of Dirac in terms of compression ratio, PSNR, SSIM and VQM in comparison with H.264 as a reference are discussed. Related issues such as transcoding and streaming over packat erasure channel are also discussed.

DESIGN AND IMPLEMENTATION OF WAVELET-DOMAIN VIDEO COMPRESSION USING MULTIRESOLUTION MOTION ESTIMATION AND COMPENSATION

2006 ◽  
Vol 06 (04) ◽  
pp. 533-549
Author(s):  
WEITING CAI ◽  
MALEK ADJOUADI
Keyword(s):  
Motion Estimation ◽  
Video Compression ◽  
Discrete Wavelet ◽  
Wavelet Domain ◽  
Blocking Artifacts ◽  
Bandwidth Utilization ◽  
Video Codecs ◽  
Block Based ◽  
Entropy Encoding ◽  
Multiresolution Motion Estimation

Video compression techniques have been applied routinely in order to conserve storage space and minimize bandwidth utilization in various video applications. To reduce inter-pixel redundancies inside and between video frames, video codecs (coder/decoder or compression/decompression) are mainly characterized by applying motion estimation and motion compensation (MEMC) in combination with discrete cosine transform (DCT). However, blocking artifacts are obvious from the block-based motion estimation and transformation, especially at low bit rates. Due to the intrinsic advantages of multiresolution and scalability of discrete wavelet transform (DWT), video compression techniques have been infused with exciting prospects by the beneficial integration of motion estimation and wavelet transformation. The contributions of this paper are in (1) proposing a design architecture of the wavelet-domain encoder and decoder; (2) implementing the multiresolution motion estimation and compensation method; and in (3) realizing the dynamic entropy encoding and decoding, so as to achieve more efficient video compression than the conventional spatial domain methods for low bit rate applications without the annoying blocking artifacts.

Fuzzy Holoentropy-Based Adaptive Inter-Prediction Mode Selection for H.264 Video Coding

2019 ◽  
Vol 10 (2) ◽  
pp. 42-60
Author(s):  
Srinivas Bachu ◽  
N. Ramya Teja
Keyword(s):  
Video Coding ◽  
Video Compression ◽  
High Performance ◽  
Mode Selection ◽  
Rate Distortion ◽  
Computation Time ◽  
Exhaustive Search ◽  
Inter Prediction ◽  
Major Drawback ◽  
Prediction Mode

Due to the advancement of multimedia and its requirement of communication over the network, video compression has received much attention among the researchers. One of the popular video codings is scalable video coding, referred to as H.264/AVC standard. The major drawback in the H.264 is that it performs the exhaustive search over the interlayer prediction to gain the best rate-distortion performance. To reduce the computation overhead due to exhaustive search on mode prediction process, this paper presents a new technique for inter prediction mode selection based on the fuzzy holoentropy. This proposed scheme utilizes the pixel values and probabilistic distribution of pixel symbols to decide the mode. The adaptive mode selection is introduced here by analyzing the pixel values of the current block to be coded with those of a motion compensated reference block using fuzzy holoentropy. The adaptively selected mode decision can reduce the computation time without affecting the visual quality of frames. Experimentation of the proposed scheme is evaluated by utilizing five videos, and from the analysis, it is evident that proposed scheme has overall high performance with values of 41.367 dB and 0.992 for PSNR and SSIM respectively.

scholarly journals Layer Selection in Progressive Transmission of Motion-Compensated JPEG2000 Video

Electronics ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 1032 ◽  
Author(s):  
José Carmelo Maturana-Espinosa ◽  
Juan Pablo García-Ortiz ◽  
Daniel Müller ◽  
Vicente González-Ruiz
Keyword(s):  
Rate Distortion ◽  
Video Codec ◽  
Experimental Comparison ◽  
Temporal Filtering ◽  
Video Codecs ◽  
File Formats ◽  
Motion Jpeg2000 ◽  
High Level ◽  
Temporal Redundancy ◽  
Client Side

MCJ2K (Motion-Compensated JPEG2000) is a video codec based on MCTF (Motion- Compensated Temporal Filtering) and J2K (JPEG2000). MCTF analyzes a sequence of images, generating a collection of temporal sub-bands, which are compressed with J2K. The R/D (Rate-Distortion) performance in MCJ2K is better than the MJ2K (Motion JPEG2000) extension, especially if there is a high level of temporal redundancy. MCJ2K codestreams can be served by standard JPIP (J2K Interactive Protocol) servers, thanks to the use of only J2K standard file formats. In bandwidth-constrained scenarios, an important issue in MCJ2K is determining the amount of data of each temporal sub-band that must be transmitted to maximize the quality of the reconstructions at the client side. To solve this problem, we have proposed two rate-allocation algorithms which provide reconstructions that are progressive in quality. The first, OSLA (Optimized Sub-band Layers Allocation), determines the best progression of quality layers, but is computationally expensive. The second, ESLA (Estimated-Slope sub-band Layers Allocation), is sub-optimal in most cases, but much faster and more convenient for real-time streaming scenarios. An experimental comparison shows that even when a straightforward motion compensation scheme is used, the R/D performance of MCJ2K competitive is compared not only to MJ2K, but also with respect to other standard scalable video codecs.

Block-Based Motion Estimation

2021 ◽  
pp. 651-676
Author(s):  
Shaifali Madan Arora ◽  
Kavita Khanna
Keyword(s):  
Video Coding ◽  
Resource Utilization ◽  
Video Compression ◽  
Visual Information ◽  
Video Data ◽  
Technological Evolution ◽  
High Bandwidth ◽  
Block Based ◽  
The Cost ◽  
And Storage

Recent years have witnessed a great technological evolution in video display and capturing technologies leading to the development of new standards of video coding including MPEG-X, H.26X and HEVC. The cost of computations, storage and high bandwidth requirements makes a video data expensive in terms of transmission and storage. This makes video compression absolutely necessary prior to its transmission in order to accommodate for different transmission media's capabilities. Digital video compression technologies therefore have become an important part of the way we create, present, communicate and use visual information. The main aim behind a video compression system is to eliminate the redundancies from a raw video signal. The tradeoff involved in the process of video compression is between the speed, quality and resource utilization. The current chapter explores the techniques, challenges, issues and problems in video compression in detail along with the major advancements in the field.

scholarly journals Fast Mode Decision Algorithm Through Inter-View Rate-Distortion Prediction for Multiview Video Coding System

2014 ◽  
Vol 10 (1) ◽  
pp. 594-603 ◽  
Author(s):  
Chia-Hung Yeh ◽  
Ming-Feng Li ◽  
Mei-Juan Chen ◽  
Ming-Chieh Chi ◽  
Xin-Xian Huang ◽  
...  
Keyword(s):  
Video Coding ◽  
Rate Distortion ◽  
Mode Decision ◽  
Fast Mode ◽  
Coding System ◽  
Decision Algorithm ◽  
Fast Mode Decision ◽  
Multiview Video Coding ◽  
Multiview Video

scholarly journals A signal adaptive diffusion filter for video coding: improved parameter selection

2019 ◽  
Vol 8 ◽  
Author(s):  
Jennifer Rasch ◽  
Jonathan Pfaff ◽  
Michael Schäfer ◽  
Anastasia Henkel ◽  
Heiko Schwarz ◽  
...  
Keyword(s):  
Video Compression ◽  
Adaptive Filters ◽  
Random Access ◽  
Rate Distortion ◽  
Filter Method ◽  
High Definition ◽  
Video Codecs ◽  
Diffusion Filter ◽  
Filter Methods ◽  
Modern Image

Abstract In this paper we combine video compression and modern image processing methods. We construct novel iterative filter methods for prediction signals based on Partial Differential Equation (PDE)-based methods. The central idea of the signal adaptive filters is explained and demonstrated geometrically. The meaning of particular parameters is discussed in detail. Furthermore, thorough parameter tests are introduced which improve the overall bitrate savings. It is shown that these filters enhance the rate-distortion performance of the state-of-the-art hybrid video codecs. In particular, based on mathematical denoising techniques, two types of diffusion filters are constructed: a uniform diffusion filter using a fixed filter mask and a signal adaptive diffusion filter that incorporates the structures of the underlying prediction signal. The latter has the advantage of not attenuating existing edges while the uniform filter is less complex. The filters are embedded into a software based on HEVC with additional QTBT (Quadtree plus Binary Tree) and MTT (Multi-Type-Tree) block structure. Overall, the diffusion filter method achieves average bitrate savings of 2.27% for Random Access having an average encoder runtime increase of 19% and 17% decoder runtime increase. For UHD (Ultra High Definition) test sequences, bitrate savings of up to 7.36% for Random Access are accomplished.

FPGA-Based ROI Encoding for HEVC Video Bitrate Reduction

2020 ◽  
Vol 29 (11) ◽  
pp. 2050182
Author(s):  
Zhilei Chai ◽  
Shen Li ◽  
Qunfang He ◽  
Mingsong Chen ◽  
Wenjie Chen
Keyword(s):  
Data Storage ◽  
Video Compression ◽  
High Efficiency ◽  
Video Quality ◽  
Region Of Interest ◽  
Absolute Difference ◽  
High Efficiency Video Coding ◽  
High Definition ◽  
Mapping Algorithm ◽  
Block Based

The explosive growth of video applications has produced great challenges for data storage and transmission. In this paper, we propose a new ROI (region of interest) encoding solution to accelerate the processing and reduce the bitrate based on the latest video compression standard H.265/HEVC (High-Efficiency Video Coding). The traditional ROI extraction mapping algorithm uses pixel-based Gaussian background modeling (GBM), which requires a large number of complex floating-point calculations. Instead, we propose a block-based GBM to set up the background, which is in accord with the block division of HEVC. Then, we use the SAD (sum of absolute difference) rule to separate the foreground block from the background block, and these blocks are mapped into the coding tree unit (CTU) of HEVC. Moreover, the quantization parameter (QP) is adjusted according to the distortion rate automatically. The experimental results show that the processing speed on FPGA has reached a real-time level of 22 FPS (frames per second) for full high-definition videos ([Formula: see text]), and the bitrate is reduced by 10% on average with stable video quality.

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