This is documentation of an archived release.
For documentation on the current version, please check Knowledge Base.
For documentation on the current version, please check Knowledge Base.
Image World File
A world file is a plain text file used by geographic information systems to georeference raster map images. Small-scale rectangular raster image maps can have an associated world file for GIS map software which describes the location, scale and rotation of the map. These world files are six-line files with decimal numbers on each line.
World files do not specify a coordinate system.
This information is generally stored in another companion file, the Orbit Resource Descriptor File (ORD)
This information is generally stored in another companion file, the Orbit Resource Descriptor File (ORD)
Structure
An world file is a plain text file used by Orbit to georeference an image file. The world file is always associated with an OMI file : it describes the location, scale and rotation of the map. These world files are six-line files with decimal numbers on each line.
Create
Create and edit these files using a text editor. Take care of spelling and file syntax.
Parameters
- Line 1: pixel size in the x-direction in map units/pixel
- Line 2: rotation about y-axis
- Line 3: rotation about x-axis
- Line 4: pixel size in the y-direction in map units
- Line 5: x-coordinate of the center of the upper left pixel
- Line 6: y-coordinate of the center of the upper left pixel
Examples of Associated World Files
Format | Image Data File | Image World File |
---|---|---|
Orbit Multiresolution Image | .omi | .oiw |
ECW | .ecw | - |
Bitmap | .bmp | .bpw |
Graphics Interchange Format | .gif | .gfw |
JPEG | .jpg | .jgw |
Portable Network Graphics | .png | .pgw |
Mister Sid | .sid | .sdw |
Tagged Image File Format | .tif(f) | .tfw |
Last modified:: 2019/03/25 11:36