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Review on fast motion estimation algorithms for HEVC in video communication
Published in Arun Kumar Sinha, John Pradeep Darsy, Computer-Aided Developments: Electronics and Communication, 2019
K. Mohan Kumar, P.K.V. Anirudh, S Yallamandaiah
Video compression is the process of encoding a video file in such a way that it occupies less space than the original file [1]. The size of video file is reduced by eliminating redundant and non-functional data from the original video file. A raw video contains immense amount of data. It contains a lot of redundant information which contains duplicate and irrelevant data. Communication and storage capabilities are limited and expensive [2]. Video compression can reduce the storage space by removing the unnecessary information, which reduces our investment on storing the video. Video compression is necessary to achieve a good quality video with minimum size. Compression of video plays a crucial part in online video streaming, broadcasting and other storage applications. The higher the compression of video, the lesser is the memory needed to store it.
Basics of Video Compression and Motion Analysis
Published in Maheshkumar H. Kolekar, Intelligent Video Surveillance Systems, 2018
Compression reduces the amount of data for transmission and storage purposes. In video compression techniques, redundant video data is removed in order to reduce the size of a digital video file. As a result of that, the space required for storage is reduced and such files can be easily sent over the network. The compression techniques can be classified as data compression and image compression.
Current Status of Information Security Based on Hybrid Crypto and Stego Systems
Published in Ibrahiem M. M. El Emary, Anna Brzozowska, Shaping the Future of ICT, 2017
Rana Saad Mohammed, Sattar B. Sadkhan
Steganography can use all types of digital file formats for hiding information, but works best with those formats that have more redundant bits than necessary to embed secret message bits. The basic types of digital file formats that can be used with steganography are text, image, audio, video, and protocol [8]. Text file format—A secret message can be hidden in each character of the word in a cover text. This method has decreased in use since the advent of other digital file formats. Also text files do not have much redundant data to hide a message.Image file format—A secret message can hide in a cover image using a specific algorithm and stego-key to get a stego image. The receiver can extract the message from a stego image using the same stego-key as the sender. There are several techniques for the image file format: Spatial domain techniques—Least significant bit, pseudorandom permutation, palette-based image, cover regions and parity bits, quantization and dithering, image, downgrading and cover channelsMasking and filteringTransform techniquesStatistical methodsSpread spectrumDistortion techniquesCover generation techniquesFile and palette embeddingAudio file format—Examples of digital audio file format are WAVE, MIDI, AVI, and MPEG. This technique hides information in cover sound parts that are unnoticeable by the human ear.Video file format—Examples of digital video format are H.264, Mp4, MPEG, and AVI. These formats can be used for hiding any kind of secret message.Protocol steganography—The protocols TCP, UDP, ICMP, and IP are used in information hiding. For example, a secret message is embedded in a header of a protocol packet [10].
Lower limb stiffness testing in athletic performance: a critical review
Published in Sports Biomechanics, 2021
Sean J. Maloney, Iain M. Fletcher
The accurate determination of angular displacements had previously necessitated the use of expensive two- (or even three-) dimensional motion capture systems. However, given recent advancements in mobile technology, video analysis at an appropriate frame rate (≥200 Hz (Farley et al., 1998; Kuitunen et al., 2011)) is now possible for most practitioners. For example, iPhone models post-2014 (models 6 and above) are capable of recording at 240 Hz. Such technological advancements could bring the determination of joint stiffness into the realms of coaches and practitioners working in a gym-based setting if they have the capacity to obtain (i.e., force plates) or estimate (i.e., using equations proposed by Dalleau et al. (2004)) force measurements and existing motion capture software that will accept the relevant video file format. However, the reliability and validity of such measures are yet to be determined.