Signal processing captures, interprets, describes and manipulates physical phenomena. Mathematics, statistics, probability, and stochastic processes are among the signal processing languages we use to interpret real-world phenomena, model them, and extract useful information. This book presents different kinds of signals humans use and applies them for human machine interaction to communicate.
Signal Processing and Machine Learning with Applications presents methods that are used to perform various Machine Learning and Artificial Intelligence tasks in conjunction with their applications. It is organized in three parts: Realms of Signal Processing; Machine Learning and Recognition; and Advanced Applications and Artificial Intelligence. The comprehensive coverage is accompanied by numerous examples, questions with solutions, with historical notes. The book is intended for advanced undergraduate and postgraduate students, researchers and practitioners who are engagedwith signal processing, machine learning and the applications.
Part I Realms of Signal Processing.- 1 Digital Signal Representation.-
1.1 Introduction.- 1.2 Numbers.- 1.2.1 Numbers and Numerals.- 1.2.2 Types of
Numbers.- 1.2.3 Positional Number Systems.- 1.3 Sampling and Reconstruction
of Signals.- 1.3.1 Scalar Quantization.- 1.3.2 Quantization Noise.- 1.3.3
Signal-To-Noise Ratio.- 1.3.4 Transmission Rate.- 1.3.5 Nonuniform
Quantizer.- 1.3.6 Companding.- 1.4 Data Representations.- 1.4.1 Fixed-Point
Number Representations.- 1.4.2 Sign-Magnitude Format.- 1.4.3 Ones-Complement
Format.- 1.4.4 Twos-Complement Format.- 1.5 Fix-Point DSPs.- 1.6
Fixed-Point Representations Based on Radix-Point.- 1.7 Dynamic Range.- 1.8
Precision.- 1.9 Background Information.- 1.10 Exercises.- 2 Signal Processing
Background.- 2.1 Basic Concepts.- 2.2 Signals and Information.- 2.3 Signal
Processing.- ix.- x Contents.- 2.4 Discrete Signal Representations.- 2.5
Delta and Impulse Function.- 2.6 Parsevals Theorem.- 2.7 Gibbs Phenomenon.-
2.8 Wold Decomposition.- 2.9 State Space Signal Processing.- 2.10 Common
Measurements.- 2.10.1 Convolution.- 2.10.2 Correlation.- 2.10.3 Auto
Covariance.- 2.10.4 Coherence.- 2.10.5 Power Spectral Density (PSD).- 2.10.6
Estimation and Detection.- 2.10.7 Central Limit Theorem.- 2.10.8 Signal
Information Processing Types.- 2.10.9 Machine Learning.- 2.10.10Exercises.- 3
Fundamentals of Signal Transformations.- 3.1 Transformation Methods.- 3.1.1
Laplace Transform.- 3.1.2 Z-Transform .- 3.1.3 Fourier Series.- 3.1.4 Fourier
Transform.- 3.1.5 Discrete Fourier Transform and Fast Fourier Transform .-
3.1.6 Zero Padding.- 3.1.7 Overlap-Add and Overlap-Save Convolution.-
Algorithms.- 3.1.8 Short Time Fourier Transform (STFT).- 3.1.9 Wavelet
Transform.- 3.1.10 Windowing Signal and the DCT Transforms.- 3.2 Analysis and
Comparison of Transformations.- 3.3 Background Information.- 3.4 Exercises.-
3.5 References.- 4 Digital Filters.- 4.1 Introduction.- 4.1.1 FIR and IIR
Filters.- 4.1.2 Bilinear Transform.-4.2 Windowing for Filtering.- 4.3 Allpass
Filters.- 4.4 Lattice Filters.- 4.5 All-Zero Lattice Filter.- 4.6 Lattice
Ladder Filters.- Contents xi.- 4.7 Comb Filter.- 4.8 Notch Filter.- 4.9
Background Information.- 4.10 Exercises.- 5 Estimation and Detection.- 5.1
Introduction.- 5.2 Hypothesis Testing.- 5.2.1 Bayesian Hypothesis Testing.-
5.2.2 MAP Hypothesis Testing.- 5.3 Maximum Likelihood (ML) Hypothesis
Testing.- 5.4 Standard Analysis Techniques.- 5.4.1 Best Linear Unbiased
Estimator (BLUE).- 5.4.2 Maximum Likelihood Estimator (MLE).- 5.4.3 Least
Squares Estimator (LSE).- 5.4.4 Linear Minimum Mean Square Error Estimator.-
(LMMSE).- 5.5 Exercises.- 6 Adaptive Signal Processing.- 6.1 Introduction.-
6.2 Parametric Signal Modeling.- 6.2.1 Parametric Estimation.- 6.3 Wiener
Filtering.- 6.4 Kalman Filter.- 6.4.1 Smoothing.- 6.5 Particle Filter.- 6.6
Fundamentals of Monte Carl.- 6.6.1 Importance Sampling (IS).- 6.7
Non-Parametric Signal Modeling.- 6.8 Non-Parametric Estimation.- 6.8.1
Correlogram.- 6.8.2 Periodogram.- 6.9 Filter Bank Method.- 6.10 Quadrature
Mirror Filter Bank (QMF).- 6.11 Background Information.- 6.12 Exercises.- 7
Spectral Analysis.- 7.1 Introduction.- 7.2 Adaptive Spectral Analysis.- 7.3
Multivariate Signal Processing.- 7.3.1 Sub-band Coding and Subspace
Analysis.- 7.4 Wavelet Analysis.- 7.5 Adaptive Beam Forming.- xii Contents.-
7.6 Independent Component Analysis (ICA).- 7.7 Principal Component Analysis
(PCA).- 7.8 Best Basis Algorithms.- 7.9 Background Information.- 7.10
Exercises.- Part II Machine Learning and Recognition.- 8 General Learning.-
8.1 Introduction to Learning.- 8.2 The Learning Phases.- 8.2.1 Search and
Utility.- 8.3 Search.- 8.3.1 General Search Model.- 8.3.2 Preference
relations.- 8.3.3 Different learning methods.- 8.3.4 Similarities .- 8.3.5
Learning to Recognize.- 8.3.6 Learning again.- 8.4 Background Information.-
8.5 Exercises.- 9 Signal Processes, Learning, and Recognition.- 9.1
Learning.- 9.2Bayesian Formalism.- 9.2.1 Dynamic Bayesian Theory.- 9.2.2
Recognition and Search.- 9.2.3 Influences.- 9.3 Subjectivity.- 9.4 Background
Information.- 9.5 Exercises.- 10 Stochastic Processes.- 10.1 Preliminaries on
Probabilities.- 10.2 Basic Concepts of Stochastic Processes.- 10.2.1 Markov
Processes.- 10.2.2 Hidden Stochastic Models (HSM).- 10.2.3 HSM Topology.-
10.2.4 Learning Probabilities.- 10.2.5 Re-estimation.- 10.2.6 Redundancy.-
10.2.7 Data Preparation.- 10.2.8 Proper Redundancy Removal.- 10.3 Envelope
Detection.- 10.3.1 Silence Threshold Selection.- 10.3.2 Pre-emphasis.-
Contents xiii.- 10.4 Several Processes.- 10.4.1 Similarity.- 10.4.2 The
Local-Global Principle.- 10.4.3 HSM Similarities.- 10.5 Conflict and
Support.- 10.6 Examples and Applications.- 10.7 Predictions.- 10.8 Background
Information.- 10.9 Exercises.- 11 Feature Extraction.- 11.1 Feature
Extractions.- 11.2 Basic Techniques.- 11.2.1 Spectral Shaping.- 11.3 Spectral
Analysis and Feature Transformation.- 11.3.1 Parametric Feature
Transformations and Cepstrum.- 11.3.2 Standard Feature Extraction
Techniques.- 11.3.3 Frame Energy.- 11.4 Linear Prediction Coe_cients (LPC).-
11.5 Linear Prediction Cepstral Coe_cients (LPCC).- 11.6 Adaptive Perceptual
Local Trigonometric Transformation.- (APLTT).- 11.7 Search.- 11.7.1 General
Search Model.- 11.8 Predictions.- 11.8.1 Purpose.- 11.8.2 Linear Prediction.-
11.8.3 Mean Squared Error Minimization.- 11.8.4 Computation of Probability of
an Observation Sequence.- 11.8.5 Forward and Backward Prediction.- 11.8.6
Forward-Backward Prediction.- 11.9 Background Information.- 11.10Exercises.-
12 Unsupervised Learning.- 12.1 Generalities.- 12.2 Clustering Principles.-
12.3 Cluster Analysis Methods.- 12.4 Special Methods.- 12.4.1 K-means.-
12.4.2 Vector Quantization (VQ).- 12.4.3 Expectation Maximization (EM).-
12.4.4 GMM Clustering.- 12.5 Background Information.- 12.6 Exercises.- xiv
Contents.- 13 Markov Model and Hidden Stochastic Model.-13.1 Markov Process.-
13.2 Gaussian Mixture Model (GMM).- 13.3 Advantages of using GMM.- 13.4
Linear Prediction Analysis.- 13.4.1 Autocorrelation Method.- 13.4.2
Yule-Walker Approach.- 13.4.3 Covariance Method.- 13.4.4 Comparison of
Correlation and Covariance methods.- 13.5 The ULS Approach.- 13.6 Comparison
of ULS and Covariance Methods.- 13.7 Forward Prediction.- 13.8 Backward
Prediction.- 13.9 Forward-Backward Prediction.- 13.10Baum-Welch Algorithm.-
13.11Viterbi Algorithm.- 13.12Background Information.- 13.13Exercises.- 14
Fuzzy Logic and Rough Sets.- 14.1 Rough Sets.- 14.2 Fuzzy Sets.- 14.2.1 Basis
Elements.- 14.2.2 Possibility and Necessity.- 14.3 Fuzzy Clustering.- 14.4
Fuzzy Probabilities.- 14.5 Background Information.- 14.6 Exercises.- 15
Neural Networks.- 15.1 Neural Network Types.- 15.1.1 Neural Network
Training.- 15.1.2 Neural Network Topology.- 15.2 Parallel Distributed
Processing.- 15.2.1 Forward and Backward Uses.- 15.2.2 Learning.- 15.3
Applications to Signal Processing.- 15.4 Background Information.- 15.5
Exercises.- Part III Real Aspects and Applications.- Contents xv.- 16 Noisy
Signals.- 16.1 Introduction.- 16.2 Noise Questions.- 16.3 Sources of Noise.-
16.4 Noise Measurement.- 16.5 Weights and A-Weights.- 16.6 Signal to Noise
Ratio (SNR).- 16.7 Noise Measuring Filters and Evaluation.- 16.8 Types of
noise.- 16.9 Origin of noises.- 16.10Box Plot Evaluation.- 16.11Individual
noise types.- 16.11.1Residual.- 16.11.2Mild.- 16.11.3Steady-unsteady Time
varying Noise.- 16.11.4Strong Noise.- 16.12Solution to Strong Noise: Matched
Filter.- 16.13Background Information.- 16.14Exercises.- 17 Reasoning Methods
and Noise Removal.- 17.1 Generalities.- 17.2 Special Noise Removal Methods.-
17.2.1 Residual Noise.- 17.2.2 Mild Noise.- 17.2.3 Steady-Unsteady Noise.-
17.2.4 Strong Noise.- 17.3 Poisson Distribution.- 17.3.1 Outliers and Shots.-
17.3.2 Underlying probability of Shots.- 17.4 Kalman Filter.- 17.4.1
Prediction Estimates.-17.4.2 White noise Kalman filtering.- 17.4.3
Application of Kalman filter.- 17.5 Classification, Recognition and
Learning.- 17.5.1 Summary of the used concepts.- 17.6 Principle Component
Analysis (PCA).- 17.7 Reasoning Methods.- 17.7.1 Case-Based Reasoning (CBR).-
17.8 Background Information.- 17.9 Exercises.- xvi Contents.- 18 Audio
Signals and Speech Recognition.- 18.1 Generalities of Speech.- 18.2
Categories of Speech Recognition.- 18.3 Automatic Speech Recognition.- 18.3.1
System Structure.- 18.4 Speech Production Model.- 18.5 Acoustics.- 18.6 Human
Speech Production.- 18.6.1 The Human Speech Generation.- 18.6.2 Excitation.-
18.6.3 Voiced Speech.- 18.6.4 Unvoiced Speech.- 18.7 Silence Regions.- 18.8
Glottis.- 18.9 Lips.- 18.10Plosive Speech Source.- 18.11Vocal-Tract.-
18.12Parametric and Non-Parametric Models.- 18.13Formants.- 18.14Strong
Noise.- 18.15Background Information.- 18.16Exercises.- 19 Noisy Speech.- 19.1
Introduction.- 19.2 Colored Noise.- 19.2.1 Additionaltypes of Colored Noise.-
19.3 Poisson Processes and Shots.- 19.4 Matched Filters.- 19.5 Shot Noise.-
19.6 Background Information.- 19.7 Exercises.- 20 Aspects Of Human Hearing.-
20.1 Human Ear.- 20.2 Human Auditory System.- 20.3 Critical Bands and
Scales.- 20.3.1 Mel Scale.- 20.3.2 Bark Scale.- 20.3.3 Erb Scale.- 20.3.4
Greenwood Scale.- 20.4 Filter Banks.- 20.4.1 ICA Network.- 20.4.2 Auditory
Filter Banks.- 20.4.3 Filter Banks.- Contents xvii.- 20.4.4 Mel Critical
Filter Bank.- 20.5 Psycho-acoustic Phenomena.- 20.5.1 Perceptual
Measurement.- 20.5.2 Human Hearing and Perception.- 20.5.3 Sound Pressure
Level (SPL).- 20.5.4 Absolute Threshold of Hearing (ATH).- 20.6 Perceptual
Adaptation.- 20.7 Auditory System and Hearing Model.- 20.8 Auditory Masking
and Masking Frequency.- 20.9 Perceptual Spectral Features.- 20.10Critical
Band Analysis.- 20.11Equal Loudness Pre-emphasis.- 20.12Perceptual
Transformation.- 20.13Feature Transformation.- 20.14Filters and Human Ear.-
20.15Temporal Aspects.- 20.16Background Information.- 20.17Exercises.- 21
Speech Features.- 21.1 Generalities.- 21.2 Cost Functions.- 21.3 Special
Feature Extractions.- 21.3.1 MFCC Features.- 21.3.2 Feature Transformation
applying DCT.- 21.4 Background Information.- 21.5 Exercises.- 22 Hidden
Stochastic Model for Speech.- 22.1 General.- 22.2 Hidden Stochastic Model.-
22.3 Forward and Backward Predictions.- 22.3.1 Forward Algorithm.- 22.3.2
Backward Algorithm.- 22.4 Forward-Backward Prediction.- 22.5 Burg Approach.-
22.6 Graph Search.- 22.6.1 Recognition Model with Search.- 22.7 Semantic
Issues and Industrial Applications.- 22.8 Problems with Noise.- 22.9 Aspects
of Music.- 22.10Music reception.- 22.11Background Information.-
22.12Exercises.- xviii Contents.- 23 Different Speech Applications Part A.-
23.1 Generalities.- 23.2 Example Applications.- 23.2.1 Experimental
laboratory.- 23.2.2 Health care support (everyday actions).- 23.2.3
Diagnostic support for persons with possible dementia.- 23.2.4 Noise.- 23.3
Background Information.- 23.4 Exercises.- 24 Different Speech Applications
Part B.- 24.1 Introduction.- 24.2 Discrete-Time Signals.- 24.3 Speech
Processing.- 24.3.1 Framing.- 24.3.2 Pre-emphasis.- 24.3.3 Windowing.- 24.3.4
Fourier Transform.- 24.3.5 Mel-Filtering.- 24.3.6 Mel-Frequency Cepstral
Coeffcients.- 24.4 Speech Analysis and Sound Effects Laboratory (SASE_Lab).-
24.5 Wake-Up-Word Speech Recognition.- 24.5.1 Introduction.- 24.5.2
Wake-up-Word Paradigm.- 24.5.3 Wake-Up-Word: Definition.- 24.5.4 Wake-Up-Word
System.- 24.5.5 Front-End of the Wake-Up-Word System.- 24.6 Conclusion.-
24.6.1 Wake-Up-Word: Tool Demo.- 24.6.2 Elevator Simulator.- 24.7 Background
Information.- 24.8 Exercises.- 24.9 Speech Analysis and Sound E_ects
Laboratory (SASE_Lab)" .- 25 Biomedical Signals: ECG, EEG.- 25.1 ECG
signals.- 25.1.1 Bioelectric Signals.- 25.1.2 Noise.- 25.2 EEG Signals.-
25.2.1 General properties.- 25.2.2 Signal types and properties.- 25.2.3
Disadvantages.- 25.3 Neural Network use.- 25.4 Major Research Questions.-
25.5 Background Information.- Contents xix.- 25.6 Exercises.- 26 Seismic
Signals.- 26.1 Generalities.- 26.2 Sources of seismic signals.- 26.3
Intermediate elements.- 26.4 Practical Data Sources.- 26.5 Major seismic
problems.- 26.6 Noise.- 26.7 Background Information.- 26.8 Exercises.- 27
Radar Signals.- 27.1 Introduction.- 27.2 Radar Types and Applications.- 27.3
Doppler Equations, Ambiguity Function(AF) and Matched.- Filter.- 27.4 Moving
Target Detection.- 27.5 Applications and Discussions.- 27.6 Examples.- 27.7
Background Information.- 27.8 Exercises.- 28 Visual Story Telling.- 28.1
Introduction.- 28.1.1 Common Visualization Approaches.- 28.2 Analytics and
Visualization.- 28.2.1 Visualization.- 28.2.2 Visual Data Minin.- 28.3
Communication and Visualization.- 28.4 Background Information.- 28.5
Exercises.- 29 Digital Processes and Multimedia.- 29.1 Images.- 29.1.1
DigitalImage Processing.- 29.1.2 Images as Matrices.- 29.1.3 Gray Scale
Images.- 29.2 Spatial Filtering.- 29.2.1 Linear Filtering of Images.- 29.2.2
Separable Filters.- 29.2.3 Mechanics of Linear Spatial Filtering Operation.-
29.3 Median Filtering.- 29.4 Color Equalization.- 29.4.1 Image
Transformations.- 29.4.2 Examples of Image Transformation Matrixes.- xx
Contents.- 29.5 Basic Image Statistics.- 29.6 Abstraction Levels of Images
and its Representations.- 29.6.1 Lowest Level.- 29.6.2 Geometric Level.-
29.6.3 Domain Level.- 29.6.4 Segmentation.- 29.7 Background Information.-
29.8 Exercises.- 30 Visualizations of Emergency Operation Centre.- 30.1
Introduction.- 30.2 Communications in Emergency Situations.- 30.3 Emergency
Scenario.- 30.3.1 Classification and EOC Scenario.- 30.4 Technical Aspects
and Techniques.- 30.4.1 Classification.- 30.4.2 Clustering.- 30.5 Background
Information.- 30.6 Exercises.- 31 Intelligent Interactive Communications.-
31.1 Introduction.- 31.2 Spoken Dialogue System.- 31.3 Gesture based
Interaction.- 31.4 Object Recognition and Identification.- 31.5 Visual Story
Telling.- 31.6 Virtual Environment for Personal Assistance.- 31.7 Sensor
Fusion.- 31.8 Intelligent Human Machine for Communication.- Application
Scenario.- 31.9 Background Information.- 31.10Exercises.- 32 Comparisons.-
32.1 Generalities.- 32.1.1 EEG and ECG.- 32.1.2 Speech and biomedical
applications.- 32.1.3 Seismic and biomedical signals.- 32.1.4 Speech and
Images.- 32.2 Overall.- 32.3 Background Information.- 32.3.1 General.- 32.4
Exercises.- Glossary.
Professor Michael M. Richter taught at the University of Texas at Austin and at RWTH Aachen, in addition to numerous visiting professorships. He is one of the founding scientific director of the DFKI (German Research Center for Artificial Intelligence). He taught, researched, and published extensively in the areas of mathematical logic and artificial intelligence. Professor Richter was one of the pioneers of case-based reasoning: he founded the leading European event on the subject, he led many of the key academic research projects, and demonstrated the real-world viability of the approach with successful commercial products. Michael Richter passed away during the final publishing phase of this book.
Dr. Sheuli Paul is a scientist in Defence Research and Development Canada, engaged in applied research in the areas of signal processing, machine learning, artificial intelligence and human-robot interaction. Trying to solve complex problems in interdisciplinary areas is her passion.
Dr. Veton Kėpuska is an inventor of Wake-Up-Word Speech Recognition, a method of communication with machines for which he was granted two patents. He joined Florida Institute of Technology (FIT) in 2003 and engaged in numerous research activities in speech and image processing, digital processes, and machine learning. Dr. Kėpuska won the First Annual Digital Signal Processing Design competition by applying his Wake-up-Word on embedded Analog Devices Platform. Dr. Kėpuska won numerous awards including the Kerry Bruce Clark award for teaching excellence and received numerous best paper awards.
Prof. Marius Silaghi has taught, researched, and published in the areas of artificial intelligence and networking. Professor Silaghi is involved in human-machine interaction research and proposed techniques for motion capture, speech recognition, and robotics. He founded the conference on Distributed Constraint Optimization and gave multiple tutorials on the topic at the main artificial intelligence conferences. He received numerous best paper awards.