MrSID files: Difference between revisions

From Wildsong
Jump to navigationJump to search
Brian Wilson (talk | contribs)
mNo edit summary
 
Brian Wilson (talk | contribs)
mNo edit summary
Line 1: Line 1:
MrSID is a proprietary compressed image file format of [[http://www.lizardtech.com/ LizardTech]]
MrSID is a proprietary compressed image file format of [[http://www.lizardtech.com/ LizardTech]]
It has become very popular for GIS files, especially orthophotos because it is efficient and
It has become very popular for GIS files, especially orthophotos because it is efficient and (can be) lossless.
lossless.


It is proprietary so it's not supported in GRASS.
LizardTech provides a free decoder. It is available for Windows, Linux and Solaris. It will convert MrSID images to JPG, GeoTIFF image formats. It can also scale images, extract part of an image, and a few other things. This makes it possible to use MrSID images in programs that do not support directly reading it.  


But all is not lost! The kindly folk at LizardTech supply a free decoder.
Lately I have been using [[GDAL]] a fair bit, and LizardTech also supplies a decoder that can be incorporated into GDAL at build time, so that you can read MrSID rasters with the GDAL tools. I have tested it on Linux. Works great.
It is available for Windows, Linux and Solaris. It will convert MrSID images
to JPG, GeoTIFF image formats. It can also scale images, extract part of an image,
and a few other things...


Go to the downloads area at the LizardTech site and look for "MrSID Decode"


For example, to convert a Corvallis orthophoto to a GeoTIFF
== Testing LizardTech tools ==


mrsiddecode -of tifg -i 11s5w15f_color_sw.sid -o ~/workspace/11s5w15f_color_sw.tif
This is a temporary page placed here to convey the results of a test to tech support at LizardTech.


The "-of tifg" tells it to generate a GeoTIFF not just a plain image TIFF.
=== Reprojection ===
By default it will give a progress indicator. You can turn this off if you want.
Output for the above command looked like this:


<pre>
Input: Corvallis air photo in SID format [[image:]]
mrsiddecode: (c) 2004 LizardTech, Inc. All rights reserved.


Output: reprojected using mrsidgeoencoder (fails)


input:
Output: reprojected using ArcGIS 9.3.1 Raster Reproject (works)
  width:        5501
Note, it works but output is in IMG format because ArcGIS cannot write SID.
  height:        6200
  upper-left X:  1273797.814000
  upper-left Y:  358042.349000
  X scale:      0.500000
  Y scale:      -0.500000


output:
MrSID command:
  width:         5501
 
  height:       6200
/usr/local/LizardTech/GeoExpress8/bin/mrsidgeoencoder \
  upper-left X1273797.814000
-of mg3 -lossless -towkt NAD_1927_StatePlane_Oregon_North_FIPS_3601.prj \
  upper-left Y358042.349000
-i 11s5w34f_color_ne.sid -o  11s5w34f_color_ne_nad27.sid
  X scale:       0.500000
Using local license
  Y scale:       -0.500000
Input file name: 11s5w34f_color_ne.sid
  format:       GeoTIFF
Output file name: 11s5w34f_color_ne_nad27.sid
</pre>
Output format: MrSID Generation 3
Estimated memory required: 33.7 MB
  Encoder version: 8.0.0.3065.Bob_3062_br
Encode start time: Mon Apr 11 15:53:06 2011
Encode finish time: Mon Apr 11 15:55:46 2011
Total encode time: 2 minutes, 40 seconds
  Input image size: 314.7 MB (329941728 bytes)
Output file size: 21.1 MB (22090787 bytes)
Encode ratio: 14.94:1 (lossless)
Data Cartridge not decremented
 
 
ArcGIS command:
 
[[image:screenshotReprojectRaster.png]]
 
--------------------
 
[Image:ReprojectionTest.jpg]]
 
[Image:ReprojectionTest.mxd]] ArcGIS ArcMAP 9.3.1 project file used to generate above image.

Revision as of 23:09, 11 April 2011

MrSID is a proprietary compressed image file format of [LizardTech] It has become very popular for GIS files, especially orthophotos because it is efficient and (can be) lossless.

LizardTech provides a free decoder. It is available for Windows, Linux and Solaris. It will convert MrSID images to JPG, GeoTIFF image formats. It can also scale images, extract part of an image, and a few other things. This makes it possible to use MrSID images in programs that do not support directly reading it.

Lately I have been using GDAL a fair bit, and LizardTech also supplies a decoder that can be incorporated into GDAL at build time, so that you can read MrSID rasters with the GDAL tools. I have tested it on Linux. Works great.


Testing LizardTech tools

This is a temporary page placed here to convey the results of a test to tech support at LizardTech.

Reprojection

Input: Corvallis air photo in SID format [[image:]]

Output: reprojected using mrsidgeoencoder (fails)

Output: reprojected using ArcGIS 9.3.1 Raster Reproject (works) Note, it works but output is in IMG format because ArcGIS cannot write SID.

MrSID command:

/usr/local/LizardTech/GeoExpress8/bin/mrsidgeoencoder \
-of mg3 -lossless -towkt NAD_1927_StatePlane_Oregon_North_FIPS_3601.prj \
-i 11s5w34f_color_ne.sid -o  11s5w34f_color_ne_nad27.sid
Using local license
Input file name: 11s5w34f_color_ne.sid
Output file name: 11s5w34f_color_ne_nad27.sid
Output format: MrSID Generation 3
Estimated memory required: 33.7 MB
Encoder version: 8.0.0.3065.Bob_3062_br
Encode start time: Mon Apr 11 15:53:06 2011
Encode finish time: Mon Apr 11 15:55:46 2011
Total encode time: 2 minutes, 40 seconds
Input image size: 314.7 MB (329941728 bytes)
Output file size: 21.1 MB (22090787 bytes)
Encode ratio: 14.94:1 (lossless)
Data Cartridge not decremented


ArcGIS command:


[Image:ReprojectionTest.jpg]]

[Image:ReprojectionTest.mxd]] ArcGIS ArcMAP 9.3.1 project file used to generate above image.