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GeoExpress - Knowledge Base Articles

A060406 - Decoding a MrSID file to other formats

Summary:

Windows users can use LizardTech’s free GeoViewer or the “demosaicking” functionality in the GeoExpress graphical user interface (GUI) to decode MrSID (.sid) images to other formats. Both Windows and Mac users can use the command-line tool MrSID GeoDecode to decode MrSID images to TIFF and GeoTIFF (.tif), JPEG (.jpg) and other formats.

Solution:

For Windows users:
Windows users can use LizardTech’s free GeoViewer to view MrSID images and decode them to JPEG, GeoTIFF or PNG (.png) format. Download GeoViewer at http://www.lizardtech.com/downloads/category/#viewers.

Windows users can also decode to other GeoTIFF by taking advantage of the demosaicking function of the Image Crop dialog in the GeoExpress GUI to “tile out” to GeoTIFF.

To demosaic an existing MrSID file:

  1. Add the image to the Images tab of the Job list. If you are demosaicking a MrSID image you can also add it to the Optimize tab.
  2. Choose Image Crop from the Tools menu. The Image Crop dialog appears. If you wish to view the image while you set the output tiling grid, click Show Image.
  3. In the Output Tiling subpanel, enter the number of rows and columns that you wish to split the image into. If you specify 3 rows and 4 columns the result will be 12 new image tiles.
  4. Enter a magnification factor if desired.
  5. Click OK, then encode as usual.

As a third method, Windows users can use the MrSID GeoDecode tool, available as part of the GeoExpress Command Line Utilities download at http://www.lizardtech.com/downloads/category/#tools__utilities. (Note: MG4 Decode, also available at that page, is a different utility.)

To install MrSID GeoDecode on Windows:

  1. Download the zip file to a location on your computer (such as your desktop).
  2. Extract the files to the desired location, typically: C:/Program Files/LizardTech/mrsidgeodecode_win.
  3. Add the location you chose to your PATH environment variable as outlined below.

To view or change environment variables:

  1. Right-click My Computer, and then click Properties
  2. Click the Advanced tab
  3. Click Environment variables
  4. Do one the following, for either a user or a system variable:
    • Click New to add a new variable name and value
    • Click an existing variable, and then click Edit to change its name or value

To decode a MrSID file to a JPEG file using MrSID GeoDecode:

  1. Open a command prompt using Start > Run > “cmd”.
  2. Enter the following command: 
    mrsidgeodecode -i input.sid -o output.jpg

The download includes some documentation and sample commands.

For Mac users:
The mrsiddecode utility is distributed as part of our SDK. It is free to register and download the Apple/Mac SDK at
http://developer.lizardtech.com/

This article was last updated or verified on 18 October 2012.