Unit information: Image and Video Coding in 2020/21

Unit name	Image and Video Coding
Unit code	EENGM4021
Credit points	10
Level of study	M/7
Teaching block(s)	Teaching Block 2 (weeks 13 - 24)
Unit director	Professor. David Bull
Open unit status	Not open
Pre-requisites	"EENG31400 or EENGM1400"
Co-requisites	None
School/department	School of Electrical, Electronic and Mechanical Engineering
Faculty	Faculty of Engineering

Description including Unit Aims

The need to transmit high quality images and video sequences faithfully over a variety of channel conditions and bandwidths is increasing rapidly with the growth of the digital broadcasting and personal communications markets. Some of the greatest challenges lie in the area of source coding for transmission over unreliable wireless networks to mobile terminals and in how to deal with increasing resolution, frame-rate, dynamic range and the demands of new formats. In this context, the topics to be covered include: i) how to code moving pictures efficiently such that redundant content can be removed without unduly sacrificing perceived quality, ii) how to ensure that the information can be faithfully reconstructed at the receiver in the presence of transmission losses and iii) how to implement solutions with low complexity. This module will introduce the student to the algorithms and standards currently available which address these issues as well as to emerging technology trends. Practical and relevant examples will be given throughout the course.

• Introduction: Image compression techniques, applications, requirements, a generic image/video codec.

• Basic concepts: The human visual system, image capture, sampling and display, luminance and chrominance, separation, quality assessment, rate-distortion theory.

• Transform methods for image and video coding: KLT, DCT, quantisation, performance comparisons, implementations.

• Lossless coding techniques: information and entropy, predictive coding, Huffman and arithmetic coding, performance comparisons.

• Filterbank methods for image and video coding: multirate processing, filterbanks, wavelets, quantisation and bit allocation, performance comparisons.

• Motion estimation and compensation: principles, block matching, extensions, reduced complexity implementations, sub-pixel and multiple reference frame methods, performance comparisons.

• Error resilient coding: the influence of errors, synchronisation loss, layered coding, EREC, error concealment.

• Image and video coding standards: JPEG, JPEG-2000, MPEG2/DVB, H.264/AVC, H.265/HEVC, the future. Assessment Details

Intended Learning Outcomes

On completion of this unit the student will be able to:

1. Describe the limitations of the human visual system and the psychovisual redundancy that exists in image and video content.
2. Describe the principles and capabilities of commonly adopted image and video coding schemes and how visual redundancy can be exploited.
3. Explain rate distortion trade-offs and the effects of coding artefacts on subjective performance for both filterbank and DCT based schemes.
4. Design image and video coding algorithms for both lossy and lossless compression, taking into account the influence of all stages (motion estimation, transformation, quantisation, scanning and entropy coding) in the coding process.
5. Explain the effects of channel errors on the decoded signal for both DCT and wavelet schemes and select and realise schemes for combating these effects.
6. Outline the international standards activities.

Teaching Information

Teaching will be delivered through a combination of synchronous and asynchronous sessions, including lectures, practical activities supported by drop-in sessions, problem sheets and self-directed exercises.

Assessment Information

ILOs will be assessed via an exam.

Reading and References

• Bull, D. R. Communicating Pictures: A course in image and video coding, Academic Press, 2014 (Recommended).

• Al-Mualla, M., C.N. Canagarajah, and D.R. Bull, Video Coding for Mobile Communications, Academic Press, 2002, ISBN:0-12-053079-1

• Sayood, Introduction to Data Compression, Morgan Kaufmann, 2006, ISBN:13:987-0-12-620862-7

• Richardson, The H.264 Advanced Video Compression Standard, Wiley, 2010