Multimedia Lectures

Week

Date

Topic

Slides

1

26 Febbraio

What is Multimedia; General Definition; HyperText and HyperMedia; Multimedia Applications; Multimedia System; Multimedia Components and Data

Introduction to
Multimedia

2

5 Marzo

Waveforms; Amplitude, Frequency and Phase; Decibel Scales; Signal to Noise; Signal Flow Graphs; Digital Signal Filtering; Finite Impulse Response

Digital Signal
Processing

3

19 Marzo

Frequency components of an image; Frequency Domain; Fourier Theory; 1D and 2D Fourier Transforms; Magnitude and Phase Spectrums; Time-Frequency Representation; Ideal Low-Pass Filter

Fourier Transform

4

26 Marzo

Low Pass Filters: ideal, Butterworth; Filtering Noisy Images; 2D Filtering; Examples; High Pass and Band-Pass Filters; Convolution; Fourier Transform and Convolution

Digital Filters

5

2 Aprile

Discrete v Continuous Media; Static and Continuous Media; Analog and Digital Signals; Analog­/­Digital Converter; Text and Static Data; Graphics; Images; Audio and Video, Digitising Sound; Digital Sampling; Nyquist’s Sampling Theorem

Multimedia Data
Fundamentals

6

9 Aprile

Implications of Sample Rate and Bit Size; Implications of Nyquist Sampling Theory; Common Digital Audio Formats; MIDI as a Compression Tool; Definition of MIDI; Components of a MIDI System; Basic MIDI Concepts; Hardware Aspects of MIDI; MIDI Messages; MIDI Channels; MPEG 4 Structured Audio; MPEG­4 MIDI Semantics and Control; HTML 5 and MIDI

Digital Audio: MIDI and MPEG-4
Audio Compression

7

23 Aprile

Graphic/Image File Formats; Bit­Map Images; Gray Scale Images; Dithering; 24-bit and 8-bit Color; Graphic Formats: GIF, JPEG, TIFF, PNG, EPS; RGB Colour Space; Colour Model

Multimedia Data
Graphics

8

7 Maggio

CMY Color Model; Color Video Signals; Chrominance, Luma and Luminance; Gamma Correction, Color Vision; Light Photoreceptors and Cone Sensitivity; Color Properties; NTSC Video Color; Chroma Subsampling; Aliasing and Images and Videos; Temporal Aliasing

Multimedia Data
Images and Video

9

14 Maggio

Need for Compression; Basics of Information Theory; Shannon and Kolmogorov; Lossless and Loss Compression; Lossless Compression Algorithms: Repetitive Sequence Suppression, Run-Length Encoding, Pattern Substitution, Entropy Encoding; Shannon-Fano Algorithm; Huffman Coding; Arithmetic Coding

Basic Compression
Algorithms I

10

21 Maggio

Simple Arithmetic Coding Example; Decoding; Binary Arithmetic Coding; Code generation; Arithmetic Coding; Lempel-Ziv-Welch Algorithm: Compression and Decompression; Source Coding Techniques: Transform and Differential Coding; Frequency Domain; Vector Quantization; K-Means

Basic Compression
Algorithms II

11

28 Maggio

Moving into the Frequency Domain; The Discrete Cosine Transform: Relationship between DCT and FFT; 1D DCT; DCT Example; 2D DCT; Performing DCT Computations; Compression with DCT; Separability; 2D DCT on an Image Block; 2D DCT Basis Functions

Discrete Cosine
Transform

12

4 Giugno

Basic JPEG Compression Pipeline; Major Coding Algorithms; Quantisation; Zig-zag Scan; Differential Pulse Code Modulation and Run Length Encode; Huffman Coding; Artefacts and Gibb's Phenomenon

JPEG