COMPRESSIVE TECHNIQUES APPLICABLE for VIDEO COMPRESSION Jayshree R
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On Computational Complexity of Motion Estimation Algorithms in MPEG-4 Encoder
On Computational Complexity of Motion Estimation Algorithms in MPEG-4 Encoder Muhammad Shahid This thesis report is presented as a part of degree of Master of Science in Electrical Engineering Blekinge Institute of Technology, 2010 Supervisor: Tech Lic. Andreas Rossholm, ST-Ericsson Examiner: Dr. Benny Lovstrom, Blekinge Institute of Technology Abstract Video Encoding in mobile equipments is a computationally demanding fea- ture that requires a well designed and well developed algorithm. The op- timal solution requires a trade off in the encoding process, e.g. motion estimation with tradeoff between low complexity versus high perceptual quality and efficiency. The present thesis works on reducing the complexity of motion estimation algorithms used for MPEG-4 video encoding taking SLIMPEG motion estimation algorithm as reference. The inherent prop- erties of video like spatial and temporal correlation have been exploited to test new techniques of motion estimation. Four motion estimation algo- rithms have been proposed. The computational complexity and encoding quality have been evaluated. The resulting encoded video quality has been compared against the standard Full Search algorithm. At the same time, reduction in computational complexity of the improved algorithm is com- pared against SLIMPEG which is already about 99 % more efficient than Full Search in terms of computational complexity. The fourth proposed algorithm, Adaptive SAD Control, offers a mechanism of choosing trade off between computational complexity and encoding quality in a dynamic way. Acknowledgements It is a matter of great pleasure to express my deepest gratitude to my ad- visors Dr. Benny L¨ovstr¨om and Andreas Rossholm for all their guidance, support and encouragement throughout my thesis work. -
1. in the New Document Dialog Box, on the General Tab, for Type, Choose Flash Document, Then Click______
1. In the New Document dialog box, on the General tab, for type, choose Flash Document, then click____________. 1. Tab 2. Ok 3. Delete 4. Save 2. Specify the export ________ for classes in the movie. 1. Frame 2. Class 3. Loading 4. Main 3. To help manage the files in a large application, flash MX professional 2004 supports the concept of _________. 1. Files 2. Projects 3. Flash 4. Player 4. In the AppName directory, create a subdirectory named_______. 1. Source 2. Flash documents 3. Source code 4. Classes 5. In Flash, most applications are _________ and include __________ user interfaces. 1. Visual, Graphical 2. Visual, Flash 3. Graphical, Flash 4. Visual, AppName 6. Test locally by opening ________ in your web browser. 1. AppName.fla 2. AppName.html 3. AppName.swf 4. AppName 7. The AppName directory will contain everything in our project, including _________ and _____________ . 1. Source code, Final input 2. Input, Output 3. Source code, Final output 4. Source code, everything 8. In the AppName directory, create a subdirectory named_______. 1. Compiled application 2. Deploy 3. Final output 4. Source code 9. Every Flash application must include at least one ______________. 1. Flash document 2. AppName 3. Deploy 4. Source 10. In the AppName/Source directory, create a subdirectory named __________. 1. Source 2. Com 3. Some domain 4. AppName 11. In the AppName/Source/Com directory, create a sub directory named ______ 1. Some domain 2. Com 3. AppName 4. Source 12. A project is group of related _________ that can be managed via the project panel in the flash. -
Digital Video Quality Handbook (May 2013
Digital Video Quality Handbook May 2013 This page intentionally left blank. Executive Summary Under the direction of the Department of Homeland Security (DHS) Science and Technology Directorate (S&T), First Responders Group (FRG), Office for Interoperability and Compatibility (OIC), the Johns Hopkins University Applied Physics Laboratory (JHU/APL), worked with the Security Industry Association (including Steve Surfaro) and members of the Video Quality in Public Safety (VQiPS) Working Group to develop the May 2013 Video Quality Handbook. This document provides voluntary guidance for providing levels of video quality in public safety applications for network video surveillance. Several video surveillance use cases are presented to help illustrate how to relate video component and system performance to the intended application of video surveillance, while meeting the basic requirements of federal, state, tribal and local government authorities. Characteristics of video surveillance equipment are described in terms of how they may influence the design of video surveillance systems. In order for the video surveillance system to meet the needs of the user, the technology provider must consider the following factors that impact video quality: 1) Device categories; 2) Component and system performance level; 3) Verification of intended use; 4) Component and system performance specification; and 5) Best fit and link to use case(s). An appendix is also provided that presents content related to topics not covered in the original document (especially information related to video standards) and to update the material as needed to reflect innovation and changes in the video environment. The emphasis is on the implications of digital video data being exchanged across networks with large numbers of components or participants. -
An Overview of Block Matching Algorithms for Motion Vector Estimation
Proceedings of the Second International Conference on Research in DOI: 10.15439/2017R85 Intelligent and Computing in Engineering pp. 217–222 ACSIS, Vol. 10 ISSN 2300-5963 An Overview of Block Matching Algorithms for Motion Vector Estimation Sonam T. Khawase1, Shailesh D. Kamble2, Nileshsingh V. Thakur3, Akshay S. Patharkar4 1PG Scholar, Computer Science & Engineering, Yeshwantrao Chavan College of Engineering, India 2Computer Science & Engineering, Yeshwantrao Chavan College of Engineering, India 3Computer Science & Engineering, Prof Ram Meghe College of Engineering & Management, India 4Computer Technology, K.D.K. College of Engineering, India [email protected], [email protected],[email protected], [email protected] Abstract–In video compression technique, motion estimation is one of the key components because of its high computation complexity involves in finding the motion vectors (MV) between the frames. The purpose of motion estimation is to reduce the storage space, bandwidth and transmission cost for transmission of video in many multimedia service applications by reducing the temporal redundancies while maintaining a good quality of the video. There are many motion estimation algorithms, but there is a trade-off between algorithms accuracy and speed. Among all of these, block-based motion estimation algorithms are most robust and versatile. In motion estimation, a variety of fast block based matching algorithms has been proposed to address the issues such as reducing the number of search/checkpoints, computational cost, and complexities etc. Due to its simplicity, the Fig. 1. Classification of Frames block-based technique is most popular. Motion estimation is only known for video coding process but for solving real life redundancies. -
Motion Estimation at the Decoder Sven Klomp and Jorn¨ Ostermann Leibniz Universit¨At Hannover Germany
5 Motion Estimation at the Decoder Sven Klomp and Jorn¨ Ostermann Leibniz Universit¨at Hannover Germany 1. Introduction All existing video coding standards, such as MPEG-1,2,4 or ITU-T H.26x, perform motion estimation at the encoder in order to exploit temporal dependencies within the video sequence. The estimated motion vectors are transmitted and used by the decoder to assemble a prediction of the current frame. Since only the prediction error and the motion information are transmitted, instead of intra coding the pixel values, compression is achieved. Due to block-based motion estimation, accurate compensation at object borders can only be achieved with small block sizes. Large blocks may contain several objects which move in different directions. Thus, accurate motion estimation and compensation is not possible, as shown by Klomp et al. (2010a) using prediction error variance, and small block sizes are favourable. However, the smaller the block, the more motion vectors have to be transmitted, resulting in a contradiction to bit rate reduction. 4.0 3.5 3.0 2.5 MV Backward MV Forward MV Bidirectional 2.0 RS Backward Rate (bit/pixel) RS Forward 1.5 RS Bidirectional 1.0 0.5 0.0 2 4 8 16 32 Block Size Fig. 1. Data rates of residual (RS) and motion vectors (MV) for different motion compensation techniques (Kimono sequence). 782 Effective Video Coding for MultimediaVideo Applications Coding These characteristics can be observed in Figure 1, where the rates for the residual and the motion vectors are plotted for different block sizes and three prediction techniques. -
(A/V Codecs) REDCODE RAW (.R3D) ARRIRAW
What is a Codec? Codec is a portmanteau of either "Compressor-Decompressor" or "Coder-Decoder," which describes a device or program capable of performing transformations on a data stream or signal. Codecs encode a stream or signal for transmission, storage or encryption and decode it for viewing or editing. Codecs are often used in videoconferencing and streaming media solutions. A video codec converts analog video signals from a video camera into digital signals for transmission. It then converts the digital signals back to analog for display. An audio codec converts analog audio signals from a microphone into digital signals for transmission. It then converts the digital signals back to analog for playing. The raw encoded form of audio and video data is often called essence, to distinguish it from the metadata information that together make up the information content of the stream and any "wrapper" data that is then added to aid access to or improve the robustness of the stream. Most codecs are lossy, in order to get a reasonably small file size. There are lossless codecs as well, but for most purposes the almost imperceptible increase in quality is not worth the considerable increase in data size. The main exception is if the data will undergo more processing in the future, in which case the repeated lossy encoding would damage the eventual quality too much. Many multimedia data streams need to contain both audio and video data, and often some form of metadata that permits synchronization of the audio and video. Each of these three streams may be handled by different programs, processes, or hardware; but for the multimedia data stream to be useful in stored or transmitted form, they must be encapsulated together in a container format. -
On the Accuracy of Video Quality Measurement Techniques
On the accuracy of video quality measurement techniques Deepthi Nandakumar Yongjun Wu Hai Wei Avisar Ten-Ami Amazon Video, Bangalore, India Amazon Video, Seattle, USA Amazon Video, Seattle, USA Amazon Video, Seattle, USA, [email protected] [email protected] [email protected] [email protected] Abstract —With the massive growth of Internet video and therefore measuring and optimizing for video quality in streaming, it is critical to accurately measure video quality these high quality ranges is an imperative for streaming service subjectively and objectively, especially HD and UHD video which providers. In this study, we lay specific emphasis on the is bandwidth intensive. We summarize the creation of a database measurement accuracy of subjective and objective video quality of 200 clips, with 20 unique sources tested across a variety of scores in this high quality range. devices. By classifying the test videos into 2 distinct quality regions SD and HD, we show that the high correlation claimed by objective Globally, a healthy mix of devices with different screen sizes video quality metrics is led mostly by videos in the SD quality and form factors is projected to contribute to IP traffic in 2021 region. We perform detailed correlation analysis and statistical [1], ranging from smartphones (44%), to tablets (6%), PCs hypothesis testing of the HD subjective quality scores, and (19%) and TVs (24%). It is therefore necessary for streaming establish that the commonly used ACR methodology of subjective service providers to quantify the viewing experience based on testing is unable to capture significant quality differences, leading the device, and possibly optimize the encoding and delivery to poor measurement accuracy for both subjective and objective process accordingly. -
Motion Vector Forecast and Mapping (MV-Fmap) Method for Entropy Coding Based Video Coders Julien Le Tanou, Jean-Marc Thiesse, Joël Jung, Marc Antonini
Motion Vector Forecast and Mapping (MV-FMap) Method for Entropy Coding based Video Coders Julien Le Tanou, Jean-Marc Thiesse, Joël Jung, Marc Antonini To cite this version: Julien Le Tanou, Jean-Marc Thiesse, Joël Jung, Marc Antonini. Motion Vector Forecast and Mapping (MV-FMap) Method for Entropy Coding based Video Coders. MMSP’10 2010 IEEE International Workshop on Multimedia Signal Processing, Oct 2010, Saint Malo, France. pp.206. hal-00531819 HAL Id: hal-00531819 https://hal.archives-ouvertes.fr/hal-00531819 Submitted on 3 Nov 2010 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Motion Vector Forecast and Mapping (MV-FMap) Method for Entropy Coding based Video Coders Julien Le Tanou #1, Jean-Marc Thiesse #2, Joël Jung #3, Marc Antonini ∗4 # Orange Labs 38 rue du G. Leclerc, 92794 Issy les Moulineaux, France 1 [email protected] {2 jeanmarc.thiesse,3 joelb.jung}@orange-ftgroup.com ∗ I3S Lab. University of Nice-Sophia Antipolis/CNRS 2000 route des Lucioles, 06903 Sophia Antipolis, France 4 [email protected] Abstract—Since the finalization of the H.264/AVC standard between motion vectors of neighboring frames and blocks, we and in order to meet the target set by both ITU-T and MPEG propose in this paper a method for motion vector coding based to define a new standard that reaches 50% bit rate reduction on a motion vector residuals forecast followed by an adaptive compared to H.264/AVC, many tools have efficiently improved the texture coding and the motion compensation accuracy. -
The H.264 Advanced Video Coding (AVC) Standard
Whitepaper: The H.264 Advanced Video Coding (AVC) Standard What It Means to Web Camera Performance Introduction A new generation of webcams is hitting the market that makes video conferencing a more lifelike experience for users, thanks to adoption of the breakthrough H.264 standard. This white paper explains some of the key benefits of H.264 encoding and why cameras with this technology should be on the shopping list of every business. The Need for Compression Today, Internet connection rates average in the range of a few megabits per second. While VGA video requires 147 megabits per second (Mbps) of data, full high definition (HD) 1080p video requires almost one gigabit per second of data, as illustrated in Table 1. Table 1. Display Resolution Format Comparison Format Horizontal Pixels Vertical Lines Pixels Megabits per second (Mbps) QVGA 320 240 76,800 37 VGA 640 480 307,200 147 720p 1280 720 921,600 442 1080p 1920 1080 2,073,600 995 Video Compression Techniques Digital video streams, especially at high definition (HD) resolution, represent huge amounts of data. In order to achieve real-time HD resolution over typical Internet connection bandwidths, video compression is required. The amount of compression required to transmit 1080p video over a three megabits per second link is 332:1! Video compression techniques use mathematical algorithms to reduce the amount of data needed to transmit or store video. Lossless Compression Lossless compression changes how data is stored without resulting in any loss of information. Zip files are losslessly compressed so that when they are unzipped, the original files are recovered. -
AVC, HEVC, VP9, AVS2 Or AV1? — a Comparative Study of State-Of-The-Art Video Encoders on 4K Videos
AVC, HEVC, VP9, AVS2 or AV1? | A Comparative Study of State-of-the-art Video Encoders on 4K Videos Zhuoran Li, Zhengfang Duanmu, Wentao Liu, and Zhou Wang University of Waterloo, Waterloo, ON N2L 3G1, Canada fz777li,zduanmu,w238liu,[email protected] Abstract. 4K, ultra high-definition (UHD), and higher resolution video contents have become increasingly popular recently. The largely increased data rate casts great challenges to video compression and communication technologies. Emerging video coding methods are claimed to achieve su- perior performance for high-resolution video content, but thorough and independent validations are lacking. In this study, we carry out an in- dependent and so far the most comprehensive subjective testing and performance evaluation on videos of diverse resolutions, bit rates and content variations, and compressed by popular and emerging video cod- ing methods including H.264/AVC, H.265/HEVC, VP9, AVS2 and AV1. Our statistical analysis derived from a total of more than 36,000 raw sub- jective ratings on 1,200 test videos suggests that significant improvement in terms of rate-quality performance against the AVC encoder has been achieved by state-of-the-art encoders, and such improvement is increas- ingly manifest with the increase of resolution. Furthermore, we evaluate state-of-the-art objective video quality assessment models, and our re- sults show that the SSIMplus measure performs the best in predicting 4K subjective video quality. The database will be made available online to the public to facilitate future video encoding and video quality research. Keywords: Video compression, quality-of-experience, subjective qual- ity assessment, objective quality assessment, 4K video, ultra-high-definition (UHD), video coding standard 1 Introduction 4K, ultra high-definition (UHD), and higher resolution video contents have en- joyed a remarkable growth in recent years. -
11.2 Motion Estimation and Motion Compensation 421
11.2 Motion Estimation and Motion Compensation 421 vertical component to the enhancement filter, making the overall filter separable with 3 3 support. × 11.2 MOTION ESTIMATION AND MOTION COMPENSATION Motion compensation (MC) is very useful in video filtering to remove noise and enhance signal. It is useful since it allows the filter or coder to process through the video on a path of near-maximum correlation based on following motion trajectories across the frames making up the image sequence or video. Motion compensation is also employed in all distribution-quality video coding formats, since it is able to achieve the smallest prediction error, which is then easier to code. Motion can be characterized in terms of either a velocity vector v or displacement vector d and is used to warp a reference frame onto a target frame. Motion estimation is used to obtain these displacements, one for each pixel in the target frame. Several methods of motion estimation are commonly used: • Block matching • Hierarchical block matching • Pel-recursive motion estimation • Direct optical flow methods • Mesh-matching methods Optical flow is the apparent displacement vector field d .d1,d2/ we get from setting (i.e., forcing) equality in the so-called constraint equationD x.n1,n2,n/ x.n1 d1,n2 d2,n 1/. (11.2–1) D − − − All five approaches start from this basic equation, which is really just an ide- alization. Departures from the ideal are caused by the covering and uncovering of objects in the viewed scene, lighting variation both in time and across the objects in the scene, movement toward or away from the camera, as well as rotation about an axis (i.e., 3-D motion). -
Diapositivo 1
VC 14/15 – TP16 Video Compression Mestrado em Ciência de Computadores Mestrado Integrado em Engenharia de Redes e Sistemas Informáticos Miguel Tavares Coimbra Outline • The need for compression • Types of redundancy • Image compression • Video compression VC 14/15 - TP16 - Video Compression Topic: The need for compression • The need for compression • Types of redundancy • Image compression • Video compression VC 14/15 - TP16 - Video Compression Images are great! VC 14/15 - TP16 - Video Compression But... Images need storage space... A lot of space! Size: 1024 x 768 pixels RGB colour space 8 bits per color = 2,6 MBytes VC 14/15 - TP16 - Video Compression What about video? • VGA: 640x480, 3 bytes per pixel -> 920KB per image. • Each second of video: 23 MB • Each hour of vídeo: 83 GB The death of Digital Video VC 14/15 - TP16 - Video Compression What if... ? • We exploit redundancy to compress image and video information? – Image Compression Standards – Video Compression Standards • “Explosion” of Digital Image & Video – Internet media – DVDs – Digital TV – ... VC 14/15 - TP16 - Video Compression Compression • Data compression – Reduce the quantity of data needed to store the same information. – In computer terms: Use fewer bits. • How is this done? – Exploit data redundancy. • But don’t we lose information? – Only if you want to... VC 14/15 - TP16 - Video Compression Types of Compression • Lossy • Lossless – We do not obtain an – We obtain an exact exact copy of our copy of our compressed data after compressed data after decompression. decompression. – Very high compression – Lower compression rates. rates. – Increased degradation – Freely compress / with sucessive decompress images. compression / It all depends on what we decompression.