51 Copyright © 2018, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 3 DOI: 10.4018/978-1-5225-2848-7.ch003 ABSTRACT 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 transmis- sion in order to accommodate for diferent 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 redundan- cies from a raw video signal. The tradeof 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 feld. INTRODUCTION Recent years have established a great technological evolution in video display and capturing technologies. Ease in accessibility of digital technology has made it possible to use digital camera, cable, sound, and video by the common people in day today applications. Revolutionary development in mobile phones has made video production a common task. Gone are the days when video production was possible only for specialized studios. In fact, digital video has paved way towards the development of various chal- lenging real-time applications. The transmission of video involves the conversion of analog video into its corresponding digital domain. In a NTPC signal 30 frames (Huckfield, 1992) are transmitted per second in 4:2:2 YUV format with 858 × 525 luminance samples, 429 × 525 × 2 chrominance samples, and 8 bits per samples. Block-Based Motion Estimation: Concepts and Challenges Shaifali Madan Arora MSIT, India Kavita Khanna NCU, India