Link to the UNESCO-IOC website
Link to the Bilko website
Earth from space
Annual sea surface temperature

Tutorial Content

Start         Main features:   T1   T2   T3   T4   T5   T6   T7   T8   T9   T10


Getting started

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This page contains links to all the sections of the introductory tutorial. You can access it at any time from the top menu bar, immediately under the Envisat Module banner.

Getting started

  1. Downloading and installing Bilko: About Bilko, where to find the software, recommended computer specifications, and instructions for installation.
  2. Using the Tutorial and lessons: Module structure, navigation features.
  3. Opening Bilko: The main features of the Bilko applications window.
  4. Using Bilko Help: How to use Bilko's context sensitive help program.
  5. Bilko file types: The different types of files (or documents) used in Bilko.

Introducing the main software features

The ten tutorial chapters below introduce you to basic image processing techniques commonly used with oceanographic image data, and shows you how to implement these using the Bilko software.

T1. Opening, viewing and saving images
Section introducing the different image file formats supported by Bilko, how to extract information, read individual data values, select image subsets, and create and save new images.

T2. Histograms: an aid to image interpretation
A section showing how to create frequency plots (histograms) based on the whole image or a region of interest, how to modify and save the histogram, and how to interpret and use histograms to help you interpret image data.

T3: Stretches: improving display contrast
How to use contrast stretching to enhance images and bring out features of interest. How to use Bilko's in-built stretches, and hints on designing and saving your own contrast stretch files.

T4: Palettes: using colour to enhance display
How to apply palettes to change an image from grey-scale to colour, modification of existing palettes, and design of new, custom palettes.

T5. Filters: revealing features of interest
Using Bilko's predefined filters to smooth data, detect edges or enhance roughness, and how to design and apply your own custom filters.

T6. Sets: connecting multiple images
Linking two or more images to create 3 dimensional data-sets, time series animations, and colour composite displays from multi-channel image data.

T7. Transects: changes along a line
Obtaining spectra and transects from multi-channel data-sets, and using Bilko's transect and coring functions to create time series plots and Hovmöller diagrams.

T8: Formulas: image calculations and masks
Using Bilko formula documents to apply masks and carry out calculations on connected images.

T9. Gridded images and geographical coordinates
Geocorrection of image data, co-registration of images and how to create gridded composites from images obtained by different sensors or at different times.

T10: Working with sets
Using scatter-plots and Principal Component Analysis to study multivariate data and relationships between different geophysical variables.

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Next: Opening, viewing and saving images

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