Remote Sensing and Image Interpretation

Thomas Lillesand, Ralph W. Kiefer and Jonathan Chipman describe recent developments in digital image processing to the next generation of satellite systems. This text introduces students to the latest developments in the exciting field of remote sensing and image interpretation. The text examines the basics of analog image analysis while placing greater emphasis on digitally … Continue reading “Remote Sensing and Image Interpretation”

Remote Sensing and Image Interpretation, 6th EditionThomas Lillesand, Ralph W. Kiefer and Jonathan Chipman describe recent developments in digital image processing to the next generation of satellite systems. This text introduces students to the latest developments in the exciting field of remote sensing and image interpretation.

The text examines the basics of analog image analysis while placing greater emphasis on digitally based systems and analysis techniques. The presentation is discipline neutral, so students in any field of study can gain a clear understanding of these systems and their virtually unlimited applications.

Authors also introduce basic concepts to the interpretation and measurement of objects on aerial photographs. Consideration is given to the types of film available, typical key elements used in photo interpretation and the procedures for calculating the size of objects in distance. They present the physical basis of remote sensing and the technology to measure spectral, spatial and/or temporal variations in field strength.

Stress is placed on laboratory work to ensure familiarity in using computer software to process, restore, enhance and interpret of imagery acquired from satellites. Increased emphasis is on digital image collection and analysis; expanded coverage of digital cameras, digital ortho-photo production, image interpretation for natural disaster assessment.

There is new material on the role of satellite systems in sensor webs; object-oriented digital image classification; a new appendix on radar signal concepts, terminology and units. New line drawings and many new black and white images and color plates are presented.

Introduction to Remote Sensing

1.1 What is Remote Sensing?
So, what exactly is remote sensing? For the purposes of this tutorial, we will use the following definition:
“Remote sensing is the science (and to some extent, art) of acquiring information about the Earth’s surface without actually being in contact with it. This is done by sensing and recording reflected or emitted energy and processing, analyzing, and applying that information.”
In much of remote sensing, the process involves an interaction between incident radiation and the targets of interest. This is exemplified by the use of imaging systems where the following seven elements are involved. Note, however that remote sensing also involves the sensing of emitted energy and the use of non-imaging sensors.

Interaction between incident radiation and the targets of interest

1. Energy Source or Illumination (A) – the first requirement for remote sensing is to have an energy source which illuminates or provides electromagnetic energy to the target of interest.

2. Radiation and the Atmosphere (B) – as the energy travels from its source to the target, it will come in contact with and interact with the atmosphere it passes through. This interaction may take place a second time as the energy travels from the target to the sensor.
3. Interaction with the Target (C) – once the energy makes its way to the target through the atmosphere, it interacts with the target depending on the properties of both the target and the radiation.
4. Recording of Energy by the Sensor (D) – after the energy has been scattered by, or emitted from the target, we require a sensor (remote – not in contact with the target) to collect and record the electromagnetic radiation.
5. Transmission, Reception, and Processing (E) – the energy recorded by the sensor has to be transmitted, often in electronic form, to a receiving and processing station where the data are processed into an image (hardcopy and/or digital).
6. Interpretation and Analysis (F) – the processed image is interpreted, visually and/or digitally or electronically, to extract information about the target which was illuminated.
7. Application (G) – the final element of the remote sensing process is achieved when we apply the information we have been able to extract from the imagery about the target in order to better understand it, reveal some new information, or assist in solving a particular problem.
These seven elements comprise the remote sensing process from beginning to end. We will be covering all of these in sequential order throughout the five chapters of this tutorial, building upon the information learned as we go. Enjoy the journey!