Setting up an image series for the MIT OrthoServer

This webpage describes how to set up your imagery series for online access. (If you've already done that, go on to configuring your server.)

1. Server setup: required components

Before you can serve the images online, you'll need to (i) create image pyramids for the image tiles you want to serve up, and (ii) build an image index listing basic facts about the image tiles. A set of Perl scripts performs these tasks by invoking several (binary) executables, compiled from C source code (for image manipulations). Here's what you'll need for this.

a. Perl interpreter, version 5.004 or higher

Perl for Unix (all variants): Perl may already be bundled with your Unix distribution -- if so, check that the version is at least 5.004. Installing Perl generally requires an ANSI C/C++ compiler such as gcc. Unpack these and install as directed.
Perl for Windows (ActiveState version); usually comes precompiled.

b. GCC or another ANSI C/C++ compiler

NOTE: you may not need to perform this step at all -- read on.
On our current "native" platforms (Sun/Solaris, Intel/WinNT, Alpha/OSF1), you don't need a compiler -- just use the precompiled executables listed next.
On other platforms, or if you wish to modify the existing image-processing utilities, you'll need a compiler to build executable programs from the source code.
If you're running Unix, remember that most Unix distributions include GCC or some other ANSI C/C++ compiler.
If you do need a compiler, we recommend GCC, freely available for Unix (all variants) and 32-bit Windows

c. Image-processing tools

For the current "native" platforms, you can just use precompiled executables. Unpack these into a directory listed in your PATH.
For other platforms, or if you wish to modify these utilities, you'll need to compile a few C source-code files against the NetPBM, GeoTIFF, TIFF, and/or JPEG image libraries. Build the libraries as directed, then, unpack the source code into the netpbm/pnm subdirectory and type "make" to compile. Then copy the executables into a directory listed in your PATH.

Platform	Executable	Source Code	Notes
Sun/Solaris	GZipped tar	Zip	Tested on SunOS 5.8
Intel/Linux	GZipped tar Zip	GZipped tar Zip	Tested on RedHat 7. All libraries should already be installed. No image libraries need to be built, so no need to build src from with the netpbm/pnm subdirectory.
Intel/Linux, RedHat 8	GZipped tar Zip		untested
Intel/WinNT	Zip	Zip	Tested on WinNT
Alpha/OSF1	GZipped tar	Zip

d. Perl scripts for server setup

Image indexer - this script extracts the georeferencing information for each tile, and creates a simple index file (one line per tile) used by the server. This information is stored in some sort of "header" -- either embedded in the image itself (GeoTIFF, DOQQ) or a separate file associated with the image (ESRI/SPOT).
Some of these scripts require binary executables, which you obtained earlier.
Pick the indexer corresponding to your image header format:

Header Format	GeoTIFF	USGS-DOQQ	HDR file (ESRI / SPOT)	TIFF w/ ESRI "World file"
Indexer	gtif-index.pl	doq-index.pl	hdr-index.pl	tfw-index.pl
Required executables	listgeo, tiffinfo			tiffinfo

Before running this script, you may need to adjust the first line to reflect your Perl interpreter's actual location.
To run this script, just specify the image tiles to be indexed, and redirect the output into an index file of your choosing. For example:

hdr-index.pl image1.hdr /u8/data/fa*.HDR > index.txt

perl hdr-index.pl image1.hdr /u8/data/fa*.HDR > index.txt

Image pyramid builder - This script resamples each image tile you specify into smaller and smaller TIFF versions, producing a multi-resolution "pyramid" for each tile. Later, this pyramid will let the server pick the best resolution for a map request, and to zoom in and out (that is, up and down the image pyramids).
Pick the pyramid builder corresponding to the format of your images:

Image Format	TIFF	USGS-DOQQ	BIL/Raw^*
Pyramid builder	tif-pyramid.pl	doq-pyramid.pl	bil-pyramid.pl
Requires	tifftopnm, pnmscale, pnmtotiff	doqtopnm, pnmscale, pnmtotiff	rawtoppm, rawtopgm, pnmscale, pnmtotiff

^* Requires a companion "HDR" file (SPOT/ESRI) to define rows, columns, bands, and header size.

Before running this script, you may need to adjust the first line to reflect your Perl interpreter's actual location. You'll also want to adjust a few lines near the top of the script, as indicated, to specify where you want your image pyramid stored, and what zoom levels (meters/pixel) you wish to create.
To run this script, just specify the image tiles to be resampled. For example:

tif-pyramid.pl image1.tif /u8/data/fa*.TIF ...