Introduce the student to the initial concepts and use of IDL and ENVI to: • import, analyze, and output image data. • learn to interface between ENVI input/outputs. This tutorial is designed to introduce you to the basic concepts of the ENVI software and some of its For ENVI +IDL, type envi at the UNIX command prompt. These programs (scripts) are based on the IDL programming language and are run in the IDL environment, either by loading the ENVI+IDL program or simply.
|Published (Last):||10 September 2015|
|PDF File Size:||7.12 Mb|
|ePub File Size:||11.33 Mb|
|Price:||Free* [*Free Regsitration Required]|
We’ll need more info to provide a better answer. Define user plot functions by adding a new line to the useradd. All user plot functions must have the following function definition statement: This file contains the following tutoriak. Vector whose values identify the band positions of the bad bands in the Z Profile data. This information is often stored in a.
Not sure it this will help. Voir plus Engi moins. Select one or more spectra; the corresponding spectral profiles appear in a Spectral Library Plots window.
ENVI Tutorial – ITT Visual Information Solutions – Informatique
Note the fourth and fifth lines: Yudine, looks like you have every thing you need to read the image into an IDL array. Note that 1st Derivative will be placed immediately after the Binary Encoding menu option.
A value of 1 indicates that the corresponding y-axis value is good, and a value of 0 means it is bad i.
Of course for any geospatial work outside IDL you would need to know the nominal pixel size and coordinates of at least 3 control points for image registration. This function accepts x and y data and a list of bad bands. Yudine, should there be an attachement or some details?
Geological Remote Sensing Group
Keyword variable envj must be present to receive extra variables that ENVI may need to pass into the plot function. Sign up using Facebook. Sign up using Email and Password. The Open File dialog appears. Excluding the bad bands, the function takes the first derivative of the y value and returns it to the plot window. A Spectral Library Input File dialog appears.
Type of plot function updates. ENVI calculates the second derivative spectra of all plots and displays the results in the Spectral Library Plots window. The user plot function is applied to every spectrum placed in that window until a different plot function is selected. When you understand how these functions work, close the files. The Spectral Library Viewer dialog appears. ENVI calculates the first derivative spectra of all plots and displays the results in the Spectral Library Plots window.
Then your only issue will be deciding which bands in the array to display, to combine. Yudine 27 1 3. If the plot function is defined without this keyword, then you will likely receive errors when trying to use it in ENVI. Data type 2 integer probably Sign up or log in Sign up using Google. This applies only to Z Profile windows and will be undefined for all other plot windows. A read of Michael Todd’s above note with the link to a class exercise at UIdaho should help you with syntax of the code.
On a Windows platform, this directory is in the following location where x x indicates the software version: Documents Ressources professionnelles Informatique. Post as a guest Name. When you call a user plot function, normal plot data all the spectra in the plot window are passed to the user plot function.
For this tutorial, you will copy a previously edited version of u s e r a d d. IDL seems to support reading tif files.
Introduction to IDL Programming
Tag that indicates the following definition is a plot function since u s e r a d d. The plot function is applied to the data, and the resulting data are returned to the plot window where they are displayed. Home Questions Tags Users Unanswered. If you don’t have ENVI then it is a bit harder.
The following steps outline this process. A file selection dialog appears. And the byte order is 0, i.