Remote Sensing Digital Image Analysis: An Introduction

297 Pages·1986·11.785 MB·English

by  John A. Richards (auth.)

John A. Richards
Remote Sensing Digital
Image Analysis
An Introduction
With 151 Figures
Springer-Verlag
Berlin Heidelberg GmbH 1986
John A. Richards
Centre for Remote Sensing, and
School of Electrical Engineering
and Computer Science
University of New South Wales
P.O. Box 1
Kensington NSW 2033, Australia
ISBN 978-3-662-02464-5
Library of Congress Cataloging-in-Publication Data
Richards, J.A. (John Alan), 1945-
Remote sensing digital image analysis.
Includes bibliographies and index.
1. Remote sensing. 2. Image processing-Digital
techniques. 1. Title.
G70.4.R53 1986 621.36'78 86-13754
ISBN 978-3-662-02464-5 ISBN 978-3-662-02462-1 (eBook)
DOI 10.1007/978-3-662-02462-1
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roade for other than private use, a fee is payable to >>Verwertungsgesellschaft Wort<<, Munich.
© Springer-Verlag Berlin Heidelberg 1986
Originally published by Springer-Verlag Berlin Heidelberg New York in 1986
Softcover reprint ofthe hardcover 1st edition 1986
The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific
statement, that such names are exempt from the relevant protective Jaws and regulations and therefore free for
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Typesetting: Hagedorn, Berlin.
2161/3020-543210
Preface
With the widespread availability of satellite and aircraft remote sensing image data in
digital form, and the ready access most remote sensing practitioners have to computing
systems for image interpretation, there is a need to draw together the range of digital
image processing procedures and methodologies commonly used in this field into a
single treatment. It is the intention of this book to provide such a function, at a level
meaningful to the non-specialist digital image analyst, but in sufficient detail that
algorithm limitations, alternative procedures and current trends can be appreciated.
Often the applications specialist in remote sensing wishing to make use of digital
processing procedures has had to depend upon either the mathematically detailed
treatments of image processing found in the electrical engineering and computer
science literature, or the sometimes necessarily superficial treatments given in general
texts on remote sensing. This book seeks to redress that situation.
Both image enhancement and classification techniques are covered making the
material relevant in those applications in which photointerpretation is used for
information extraction and in those wherein information is obtained by classification.
It grew out of a graduate course on digital image processing and analysis techniques for
remote sensing data given annually since 1980 at the University of New South Wales. If
used as a graduate textbook its contents with the exception of Chap. 7 can be covered
substantially in a single semester. Its function as a text is supported by the provision of
exercises at the end of each chapter. Most do not require access to a computer for
solution. Rather they are capable of hand manipulation and are included to highlight
important issues. In many cases some new material is introduced by means of these
exercises.
Each chapter concludes with a short critical bibliography that points to more
detailed treatments of specific topics and provides, where appropriate, comment on
techniques of marginal interest to the mainstream of the book's theme.
Chapter 1 is essentially a compendium of data sources commonly encountered in
digital form in remote sensing. It is provided as supporting material for the chapters
that follow, drawing out the particular properties of each data source of importance.
The second chapter deals with radiometric and geometric errors in image data and with
means for correction. This also contains material on registration of images to maps and
images to each other. Here, as in all techniques chapters, real and modelled image data
examples are given. Chapter 3 establishes the role of computer processing both for
photointerpretation by a human analyst and for machine analysis. This may be skipped
by the remote sensing professional but is an important position chapter if the book is to
be used in teaching.
Chapters 4 and 5 respectively cover the range of radiometric and geometric en
hancement techniques commonly adopted in practice, while Chap. 6 is addressed to
VI Preface
multispectral transformations of data. This includes the principal components
transformation and image arithmetic. Chapter 7 is given over to Fourier transform
ations. This material is becoming more important in remote sensing with falling
hardware costs and the ready availability of peripheral array processors. Here the
properties of discrete Fourier analysis are given along with means by which the fast
Fourier transform algorithm can be used on image data.
Chapters 8, 9 and 10 provide a treatment of the tools used in image classification,
commencing with supervised classification methods, moving through commonly used
clustering algorithms for unsupervised classification and concluding with means for
separability analysis. These are drawn together into classification methodologies in
Chap. 11 which also provides a set of case studies.
Even though the treatment provided is intended for the non-specialist image analyst,
it is still necessary that it be cast in the context of some vector and matrix algebra.
Otherwise it would be impracticable. Consequently, an appendix is provided on
essential results on vectors and matrices, and all important points in the text are
illustrated by simple worked examples. These demonstrate how vector operations are
evaluated. Beyond this material it is assumed the reader has a passing knowledge of
basic probability and statistics including an appreciation of the multivariate normal
distribution.
Several other appendices are provided to supplement the main presentation. One
deals with developments in image processing hardware and particularly the architec
ture (in block form) of interactive image display sub-systems. This material highlights
trends towards hardware implementation of image processing and illustrates how
many of the algorithms presented in the book can be executed in near real time.
Owing to common practice, some decisions have had to be taken in relation to
definitions even though they could offend the purist. For example the term "pixel"
strictly refers to a unit of digital image data and not to an area on the ground. The latter
is more properly called an effective ground resolution element. However because the
practice of referring to ground resolution elements as pixels, dimensioned in metres, is
so widespread, the current treatment seeks not to be pedantic but rather follows
common practice for simplicity. A difficulty also arises with respect to the numbering
chosen for the wavebands in the Landsat multispectral scanner. Historically these have
been referred to as bands 4 to 7 for Landsats 1 to 3. From Landsat 4 onwards they have
been renumbered as bands 1 to 4. The convention adopted herein is mixed. When a
particular satellite is evident in the discussion, the respective convention is adopted and
is clear from the context of that discussion. In other cases the convention for Landsat 4
has been used as much as possible.
Finally, it is a pleasure to acknowledge the contributions made by others to the
production of this book. The manuscript was typed by Mrs Moo Song and Mrs Ailsa
Moen, both of whom undertook the task tirelessly and with great patience and
forbearance. Assistance with computing was given by Leanne Bischof, at all times
cheerfully and accurately. The author's colleagues and students also played their part,
both through direct discussion and by that process of gradual learning that occurs over
many years of association. Particular thanks are expressed to two people. The author
counts himself fortunate to be a friend and colleague of Professor Philip Swain of
Purdue University, who in his own way, has had quite an impact on the author's
thinking about digital data analysis, particularly in remote sensing. Also, the author
Preface VII
has had the good fortune to work with Tong Lee, a graduate student with
extraordinary insight and ability, who also has contributed to the material through his
many discussions with the author on the theoretical foundations of digital image
processing.
The support and encouragement the author has received from his family during the
preparation of this work has been immeasurable. It is fitting therefore to conclude in
gratitude to Glenda, Matthew and Jennifer, for their understanding and enthusiasm.
Kensington, Australia, May 1986 John A. Richards
Contents
Chapter 1-Sources and Characteristics of Remote Sensing Image Data ..... .
1.1 Introduction to Data Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.1 Characteristics of Digital Image Data . . . . . . . . . . . . . . . . . . . . 1
1.1.2 Spectral Ranges Commonly Used in Remote Sensing . . . . . . . 2
1.1.3 Concluding Remarks........... . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Weather Satellite Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2.1 Polar Orbiting and Geosynchronous Satellites . . . . . . . . . . . . . 7
1.2.2 The NOAA AVHRR (Advanced Very High Resolution Radio-
meter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.2.3 The Nimbus CZCS (Coastal Zone Colour Scanner). . . . . . . . . 8
1.2.4 GMS VISSR (Visible and Infrared Spin Scan Radiometer). . . 8
1.3 Earth Resource Satellite Sensors in the Visible and Infrared
Regions.............................................. 9
1.3.1 The Landsat System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.3.2 The Landsat Instrument Complement . . . . . . . . . . . . . . . . . . . . 10
1.3.3 The Return Beam Vidicon (RBV) . . . . . . . . . . . . . . . . . . . . . . . . 11
1.3.4 The Multispectral Scanner (MSS) . . . . . . . . . . . . . . . . . . . . . . . . 11
1.3.5 The Thematic Mapper (TM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.3.6 The SPOT High Resolution Visible (HRV) Imaging Instrument 14
1.3.7 The Skylab S 192 Multispectral Scanner . . . . . . . . . . . . . . . . . . 14
1.3.8 The Heat Capacity Mapping Radiometer (HCMR) . . . . . . . . . 15
1.4 Aircraft Scanners in the Visible and Infrared Regions . . . . . . . 16
1.4.1 General Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.4.2 The Daedalus AADS 1240/1260 Multispectral Line Scanner . 17
1.4.3 The Airborne Thematic Mapper (ATM). . . . . . . . . . . . . . . . . . . 18
1.4.4 The Thermal Infrared Multispectral Scanner (TIMS) . . . . . . . 19
1.4.5 The MDA MEIS-11 Linear Array Aircraft Scanner . . . . . . . . . 19
1.5 Image Data Sources in the Microwave Region . . . . . . . . . . . . . 20
1.5.1 Side Looking Airborne Radar and Synthetic Aperture Radar 20
1.5.2 The Seasat SAR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.5.3 Shuttle Imaging Radar-A (SIR-A) . . . . . . . . . . . . . . . . . . . . . . . . 22
1.5.4 Shuttle Imaging Radar-B (SIR-B) . . . . . . . . . . . . . . . . . . . . . . . . 23
1.5.5 Aircraft Imaging Radar Systems . . . . . . . . . . . . . . . . . . . . . . . . . 23
1.6 Spatial Data Sources in General . . . . . . . . . . . . . . . . . . . . . . . . . 24
1.6.1 Types of Spatial Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
X Contents
1.6.2 Data Formats........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1.6.3 Geographic Information Systems (GIS) . . . . . . . . . . . . . . . . . . . 27
1.6.4 The Challenge to Image Processing and Analysis . . . . . . . . . . . 29
1. 7 A Comparison of Scales in Digital Image Data . . . . . . . . . . . . 29
References for Chapter 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Chapter 2-Error Correction and Registration of Image Data........... . . . . 33
2.1 Sources of Radiometric Distortion . . . . . . . . . . . . . . . . . . . . . . . 33
2.1.1 The Effect of the Atmosphere on Radiation . . . . . . . . . . . . . . . 33
2.1.2 Atmospheric Effects on Remote Sensing Imagery. . . . . . . . . . . 37
2.1.3 Instrumentation Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2.2 Correction of Radiometric Distortion . . . . . . . . . . . . . . . . . . . . 38
2.2.1 Detailed Correction of Atmospheric Effects . . . . . . . . . . . . . . . . 38
2.2.2 Bulk Correction of Atmospheric Effects . . . . . . . . . . . . . . . . . . . 40
2.2.3 Correction of Instrumentation Errors...... . . . . . . . . . . . . . . . 41
2.3 Sources of Geometric Distortion . . . . . . . . . . . . . . . . . . . . . . . . . 42
2.3.1 Earth Rotation Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
2.3.2 Panoramic Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
2.3.3 Earth Curvature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 7
2.3.4 Scan Time Skew. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
2.3.5 Variations in Platform Altitude, Velocity and Attitude . . . . . . 48
2.3.6 Aspect Ratio Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.3.7 Sensor Scan Nonlinearities........ . . . . . . . . . . . . . . . . . . . . . . 49
2.4 Correction of Geometric Distortion ..................... . 50
2.4.1 Use of Mapping Polynomials for Image Correction ....... . 50
2.4.1.1 Mapping Polynomials and Ground Control Points ........ . 51
2.4.1.2 Resampling .......................................... . 52
2.4.1.3 Interpolation ........................................ . 52
2.4.1.4 Choice of Control Points .............................. . 54
2.4.1.5 Example of Registration to a Map Grid ................. . 55
2.4.2 Mathematical Modelling .............................. . 58
2.4.2.1 Aspect Ratio Correction ............................... . 58
2.4.2.2 Earth Rotation Skew Correction ........................ . 58
2.4.2.3 Image Orientation to North-South ...................... . 59
2.4.2.4 Correction of Panoramic Effects ........................ . 59
2.4.2.5 Combining the Corrections ............................ . 59
2.5 Image Registration ................................... . 60
2.5.1 Georeferencing and Geocoding ......................... . 60
2.5.2 Image to Image Registration ........................... . 60
2.5.3 Sequential Similarity Detection Algorithm ............... . 61
2.5.4 Example of Image to Image Registration ................. . 61
Contents XI
2.6 Miscellaneous Image Geometry Operations . . . . . . . . . . . . . . . 64
2.6.1 Image Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
2.6.2 Scale Changing and Zooming . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
References for Chapter 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Chapter 3-The Interpretation of Digital Image Data . . . . . . . . . . . . . . . . . . . . . 69
3.1 Two Approaches to Interpretation . . . . . . . . . . . . . . . . . . . . . . . 69
3.2 Forms of Imagery for Photointerpretation . . . . . . . . . . . . . . . . 70
3.3 Computer Processing for Photointerpretation . . . . . . . . . . . . . 73
3.4 An Introduction to Quantitative Analysis - Classification . . 75
3.5 Multispectral Space and Spectral Classes . . . . . . . . . . . . . . . . . 76
3.6 Quantitative Analysis by Pattern Recognition . . . . . . . . . . . . . 78
3.6.1 Pixel Vectors and Labelling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.6.2 Unsupervised Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
3.6.3 Supervised Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
References for Chapter 3........ . . . . . . . . . . . . . . . . . . . . . . . . 81
Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Chapter 4-Radiometric Enhancement Techniques. . . . . . . . . . . . . . . . . . . . . . . . . 83
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
4.1.1 Point Operations and Look Up Tables . . . . . . . . . . . . . . . . . . . 83
4.1.2 Scalar and Vector Images........ . . . . . . . . . . . . . . . . . . . . . . . 83
4.2 The Image Histogram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
4.3 Contrast Modification in Image Data . . . . . . . . . . . . . . . . . . . . 86
4.3.1 Histogram Modification Rule . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
4.3.2 Linear Contrast Enhancement . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
4.3.3 Saturating Linear Contrast Enhancement . . . . . . . . . . . . . . . . . 89
4.3.4 Automatic Contrast Enhancement . . . . . . . . . . . . . . . . . . . . . . . 90
4.3.5 Logarithmic and Exponential Contrast Enhancement . . . . . . . 90
4.3.6 Piecewise Linear Contrast Modification . . . . . . . . . . . . . . . . . . 90
4.4 Histogram Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
4.4.1 Use of the Cumulative Histogram........................ 91
4.4.2 Anomalies in Histogram Equalization . . . . . . . . . . . . . . . . . . . . 95
4.5 Histogram Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
4.5.1 Principle of Histogram Matching . . . . . . . . . . . . . . . . . . . . . . . . 96
4.5.2 Image to Image Contrast Matching . . . . . . . . . . . . . . . . . . . . . . 97
4.5.3 Matching to a Mathematical Reference . . . . . . . . . . . . . . . . . . . 98