Some basic operations of ENVI

Background transparent display

• Action: Use Ignored Value (Data Ignore Value)

• To do: in the Toolbox: Raster Management found under Edit ENVI Header, then select the image data you want to modify, and then under Set Raster Metadata window, click + Add ..., then select Data Ignore Value on the inside, ( If there are wood, it has been added to the Set Raster Metadata window) after finding the Set Raster Metadata window, change the value to 0, to complete it.

---

Before performing radiometric calibration, modify the scaling parameters

• The reason: Because scaling parameters before the domestic satellite is updated every year, so during the radiometric calibration, need to modify the calibration parameters.

• Action: Set Raster Metadata window, modify

• Specific operation:

1. See scaling parameters (Gain Gain, Offset Offset): The Layer Manager window, the layer right to view, select View Metadata (view metadata), click Spectral (grating), and then view Radiance Gains Radiance Offsets .

2. Modify the calibration parameters : In View Metadata window, click on the bottom right corner of the Edit Metadata, and then in the Set Raster Metadata window, find the Data Gain Values and Data Offset Values, modified.

---

Change the name of the color image classification categories

• Action: Set Raster Metadata window, modify the Class Names and Class Colors.

• To do: in the Toolbox: Raster Management found under Edit ENVI Header, then select the image data you want to modify, and then under Set Raster Metadata window, modify the Class Names and Class Colors.

---

Modify projected coordinate system

• Specific operation:

1. View coordinate system : In the Layer Manager window, right-layer you want to view, select View Metadata (view metadata), click Cordinate System view coordinate information.

2. Modify the coordinate system : In View Metadata window, click on the bottom right corner of the Edit Metadata, and then in the Set Raster Metadata window, find Spatial

Reference (spatial reference), modified.

---

Custom coordinate ENVI

• Analysis: modify the file . ENVI want in a custom coordinate system, simply store the coordinates of the given content file modifications.

• Coordinate definition file: ellipse.txt (ellipsoid parameters file), datum.txt (profile plane), map_proj.txt (coordinate system parameter file)

• File location: as ENVI5.3, Exelis \ ENVI53 \ classic \ map_proj

• Defined coordinate system steps: defining ellipsoid define the reference, defines the coordinate parameters

• Modify file syntax:

1. ellipse.txt, Syntax <ellipsoid name>, <semiaxis> <short axle>

2. datum.txt, Syntax <datum name>, <name ellipsoid> <translation and three parameters>

• Coordinate System:

1. It can be defined in a coordinate system where the modified projection.

2. Available in ENVI Classic in: Customize Map Projection in the Map (custom map projection), defined (name consistent with the projection in Arcgis) in Customized Map Projection Definition, the definition of a good will save the file to map_proj.txt in.

• Changing :( coordinate projection conversion) can be the ENVI Classic: Convert Map Projection in the Map (the conversion map projection)

---

If errors or comments, you can leave a message in the comments area Keguan Oh! ! !
This article will continue to update oh!