User’s Guide for MapIMG 2: Map Image 

Re-projection Software Package 

By Michael P Finn, Jason R. Trent, Robert A. Buehler 

Report Series 2006-1016 

U.S. Department of the Interior 

U.S. Geological Survey 
Any use of trade, product, or firm names is for descriptive purposes only and does not 

imply endorsement by the U. S. Government. 

Contents

Contents .............................................................................................................................. i

Version History ................................................................................................................. 1

Preface to Version 2.0....................................................................................................... 2

Background to MapIMG.................................................................................................. 4

General Input Information .............................................................................................. 5

Generic Binary Raster Image.......................................................................................... 5 

XML Metadata................................................................................................................ 6 

Parameter Descriptions.................................................................................................... 7

Running MapIMG ............................................................................................................ 9

Opening MapIMG 2 for the First Time .......................................................................... 9 

Actions Overview ......................................................................................................... 10 

Toolbar Buttons ........................................................................................................ 10 

Parameter Buttons..................................................................................................... 10 

Other Actions............................................................................................................ 10 

Re-projecting................................................................................................................. 11 

Modifying Input Parameters ......................................................................................... 14 

Modifying Output Parameters....................................................................................... 15 

Choosing Resample Options......................................................................................... 16 

Using the Viewer .......................................................................................................... 17 

Other Tools ................................................................................................................... 17 

Troubleshooting ............................................................................................................ 17 

References........................................................................................................................ 19
1 

User’s Guide for MapIMG 2: Map Image Re-projection Software Package 

 

By Michael P. Finn, Jason R. Trent1, and Robert A. Buehler1 

Version History

Version 0.0 Dan Steinwand, U.S. Geological Survey (USGS)/Earth Resources 

Observation Systems (EROS) Data Center (EDC) 1995 

Version 0.0 was a command line version for UNIX that took four arguments: the 

input metadata, the output metadata, the input data file, and the output destination 

path. 

Version 1.0 Stephen Posch and Michael P. Finn, USGS/Mid Continental Mapping 

 Center (MCMC) 2003 

Version 1.0 added a GUI interface that was built using the Qt library for cross 

platform development. 

Version 1.01 Jason Trent and Michael P. Finn, USGS/MCMC 2004 

Version 1.01 suggested bounds for the parameters of each projection. Also, it added 

support for larger input files, storage of the last used input and output folders, and 

support for TIFF/GeoTIFF input images. 

Version 2.0 Robert Buehler, Jason Trent, and Michael P. Finn, USGS/National 

Geospatial Technical Operations Center (NGTOC) 2005 

Version 2.0 added Resampling Methods (Mean, Mode, Min, Max, and Sum), updated 

the GUI design, and added the viewer/pre-viewer. Also, it changed the metadata style 

to XML and switched to a new naming convention. 

 

1

 Now with the University of Missouri – Rolla, Department of Computer Science. 
2 

Preface

Significant changes for version 2.0 include a new user interface to be more similar to 

standard window applications, a viewer to show loaded files and preview re-projections, 

different resample methods beyond nearest neighbor, and XML files (a popular ASCII 

file structure for containing structured information) as the new format for the metadata 

files. 

Author, fill value, and no data value information have been added to the metadata file 

(see General Input Information for additional details). A naming convention also has 

been selected such that MapIMG is the new spelling; it will no longer be referred to as 

mapimg. 

MapIMG 2 supports more projections than were supported in MapIMG v1.01, but a few 

still remain unsupported. However, the control has now been given to the user to run 

these special projections at his or her risk. Certain projections are marked with a “Bad 

Projection” tag as shown in figure 1. 

Figure 1. Bad Projection Tag 

If the user attempts to continue with this projection, an error message will popup 

(figure 2). By clicking “Ignore” the user can continue and MapIMG will attempt to 

perform the re-projection. More often than not this course of action will result in a map of 

zero size, large amounts of extraneous data, or a crash. 

Figure 2. Bad Projection Parameters Error Message 

This feature should be quite useful if the user is a developer/programmer that is 

attempting to tweak a “Bad Projection.” An example would be working with the Polar 
3 

Stereographic projection. MapIMG transforms points near the opposite pole to be at or 

near infinite. If the developer re-programs MapIMG to skip points within 10 degrees of 

the opposite side, then running the projection would require choosing “Ignore” as 

opposed to finding and altering the code that labels Polar Stereographic as a “Bad 

Projection.” 

It should be noted that currently, MapIMG only supports raster datasets of global extent; 

therefore, calculated values only will be valid if the input is truly to a global extent.

While this user’s guide does make reference to previous versions, it also is complete for 

the current version of MapIMG. All features of the MapIMG 2 software package are 

explained in this document. 
4 

Background

Scientists routinely accomplish small-scale geospatial modeling in the raster domain, 

using high-resolution datasets for large parts of continents and low-resolution to highresolution datasets for the entire globe. Direct implementation of point-to-point 

transformation with appropriate functions yields the variety of projections available in 

commercial software packages, but implementation with data other than points requires 

specific adaptation of the transformation equations or prior preparation of the data to 

allow the transformation to succeed. It seems that some of these packages use the U.S. 

Geological Survey’s (USGS) General Cartographic Transformation Package (GCTP) or 

similar point transformations without adaptation to the specific characteristics of raster 

data (Usery and others, 2003a). 

 Usery and others (2003b) compiled and tabulated the accuracy of categorical areas in 

projected raster datasets of global extent. Based on the shortcomings identified in these 

studies, geographers and applications programmers at the USGS expanded and evolved a 

USGS software package, MapIMG, for raster map projection transformation (Finn and 

Trent, 2004). Daniel R. Steinwand of Science Applications International Corporation, 

National Center for Earth Resources Observation and Science, originally developed 

MapIMG for the USGS, basing it on GCTP. Through previous and continuing efforts at 

the USGS’ National Geospatial Technical Operations Center, this program has been 

transformed from an application based on command line input into a software package 

based on a graphical user interface for Windows, Linux, and other UNIX machines. 

MapIMG 2 is now on the Web with the User’s Guide, source, and binaries available for 

download at: 

http://carto-research.er.usgs.gov/projection/acc_proj_data.html
5 

General Input Information

Generic Binary Raster Image 

The primary file type of MapIMG is a Generic Binary raster file. MapIMG uses .img as 

the extension for these files. They contain no header data. The file is composed entirely 

of values for cells sorted in row major order. Currently, MapIMG can manipulate and 

view files with any one of a number of data types used to store the values. These data 

types are unsigned or signed, 8, 16, or 32 bit integers, and 32 or 64 bit floats. Singleimage tagged image file format (TIFF) or GeoTIFF files also may be used as input; 

however, it is highly recommended that all images be exported to Generic Binary if at all 

possible. 

If TIFF/GeoTIFF images are used, they are exported to Generic Binary format as soon as 

they are loaded. The TIFF format stores images as 32-bit color values, which are then 

extracted to Generic Binary. It is recommended that TIFF input be used only for thematic 

data; continuous data will lose all actual values and only relative values will remain. 

Band interleaved by line (BIL) is a storage format for image data. For a single band of 

data, BIL is the same as band sequential (BSQ) and band interleaved by pixel (BIP) 

(Slater, 1980). Generic Binary, as used in MapIMG (consistent with ERDAS Imagine), is 

any of these single-band formats that store data in a left-to-right, top-to-bottom row order 

(ERDAS, 1999). It allows for varying data types—for example, from 8 to 64 bit. 

CAUTION: The Generic Binary file must use the same byte ordering (endian) as the 

computer running MapIMG. The file is a raw image with absolutely no metadata, not 

even the dimensions of the image, which must be known by the user. The output also will 

be in the same raw format. 

A common naming convention is recommended to keep track of files: in particular, the 

format (type)_(proj)_(pix_size).img, where type is the type of data (theme) being used, 

proj is the projection used, and pix_size is the output file’s pixel size. For example, 

glc_sine_30sec.img would be used to represent a global land cover image in the 

sinusoidal projection with a pixel size of 30 arc-seconds. Notice that the file name always 

ends in .img, signifying a generic binary image. Although these conventions are not 

mandatory for proper program execution, they provide a useful and reliable way to keep 

track of files. 
6 

XML Metadata 

Anytime MapIMG is executed on a file, an associated XML file (figure 3) will be created 

from the parameters selected by the user for both the input and the output image. For an 

input/output file called file_name.img, the associated XML file will be named 

file_name.xml. It is not absolutely necessary to save these files, but it is highly

recommended. If the input/output files are to be used again in the future, the XML files 

will make sure the correct projection parameters are used. 

Figure 3. Sample XML File 
7 

Parameter Descriptions

Rows and Columns define the pixel dimensions of the generic binary raster image. 

Upper Left (UL) Coordinate is the measurement, in meters, that anchors the upper left 

corner, the “first cell”, of the image. The “first” cell is usually located at 90o N 180o W 

(as in this implementation for global map projections). It is measured from the location 

of the “center” cell of the image (raster file) that is generally located at 0o latitude 0o 

longitude, but can be anywhere the mapmaker defines it. The UL latitude measurement 

is the number of meters from the “center” cell to the “first” cell in the northward 

direction. Likewise, the UL longitude measurement is the number of meters from the 

“center” cell to the “first” cell in the westward direction. Figure 4 pictorially depicts the 

previous statements. 

Figure 4. Cell Reference 

Units define the units of measurement for each of the parameters. Currently only meters 

are supported. If changing units is supported in the future then it would be possible to 

enter parameters such as the upper left coordinate in units other than meters. 

Spheroid defines the shape of the earth for use in the projections. This is another 

parameter that cannot be adjusted at this time. Only a spheroid of radius 6370997 meters 

currently is supported. 

Pixel Size describes the width and height in meters of a pixel at the point of true scale in 

the image. 

Pixel Data Type describes the way each pixel’s value is stored in the image file. 

(e.g. 8 Bit Unsigned Integer and 32 Bit Float) 

Fill Value is the numeric value that MapIMG places in areas that are not part of the map. 
8 

No Data Value is used to determine places in a map where no data are present. This 

value never occurs outside the map where fill value would be placed. It is used by 

MapIMG for resampling methods where the sample being pulled from the input is full of 

ignore values. 

Ignore Values are entered on the resample form in a list at the same time that the 

parameters for the output image are changed. All values listed will not be used in 

calculations during the resample. That is, they are not part of the re-projection, but are 

there only so there will be no holes between pixels inside or outside the map frame. The 

no “data value” and “fill value” also are ignored. 
9 

Running MapIMG

MapIMG is a stand-alone program available for Windows, Linux, and Solaris. All images 

in this guide are of the Windows version, but other versions will look similar. Double 

click the MapIMG executable (mapimg2.exe) to begin execution of the program. 

Opening MapIMG 2 for the First Time 

The first time MapIMG 2 is run, the Author Properties dialog will appear as shown in 

figure 5. 

Figure 5. Author Properties Dialog 

After entering a name, company, and email address, click “Ok” to save them and 

continue. Clicking “Cancel” will continue without saving. The MapIMG main dialog 

shown in figure 6 will appear, and MapIMG is ready for use. 

Figure 6. MapIMG 2 Main Dialog 

If at any time the author fields need to be changed then choose Options Æ Edit 

Author (Ctrl+A) to display the Author Properties dialog (figure 5). 
10 

Actions Overview 

Toolbar Buttons

Open: Pressing this button displays the open file dialog and allows the user to select an IMG or 

TIFF file and load it as input. 

Re-project and Save: Assuming all parameters are filled and error free, pressing this button 

will display the save file dialog and allow the user to select a destination for their re-projection 

and specify resampling options. 

Show Input Parameters: Pressing this button toggles whether the green panel for input 

information is shown or not. 

Show Preview: Pressing this button toggles whether the preview panel is shown or not. Also, if 

the user clicks on the down arrow then they can select to show input or output previews. 

Show Output Parameters: Pressing this button toggles whether the red panel for output 

information is shown or not. 

Resample: Pressing this button will resample the viewer to the current resolution. 

(See “Using the Viewer”: page 17) 

Preview Re-projection: Pressing this button will hide the input parameters and show the 

preview panel with a small scale version of what the re-projection will look like. 

Parameter Buttons

Lock and Unlock: This button is present on the input parameters and allows the user to unlock 

and edit them. By re-locking the input the parameters are auto-saved. 

Calculate: Pressing this button will update the rows, columns, and upper left coordinates with 

their values based on the GCTP calculations using all projection info and the pixel size. 

Copy from Input: Pressing this button will copy all the values from the input list to the output 

list. This is a quick way to make minor adjustments to a projection. 

Other Actions

Save Input Parameters: This action is redundant to locking the input parameters. It will save 

the parameters in the list if they are valid and prompt if a file is about to be overwritten. 

Edit Author: Choosing this action will re-show the Author Properties dialog (figure 5) so that 

the user can change their author parameters. 

Decision Support System: This action launches the current machine’s default browser to the 

USGS website hosting the Decision Support System for Map Projections of Small Scale Data. 

About MapIMG: Choosing this action will show the About MapIMG dialog that contains a 

brief disclaimer, contact info, and a credits section for libraries used. 

About Qt: Choosing this action will show the About Qt dialog as per request by Trolltech, the 

authors of Qt. 

Exit: This action will immediately exit MapIMG. 

Do not pass GO and do not collect $200. 
11 

Re-projecting 

The first step in performing a re-projection is to load the desired input file to reproject. This is done by clicking the Open button ( ), choosing File Æ Open..., or 

pressing Ctrl+O. An Open File window (figure 7) will open that is used to select an 

IMG (generic binary) or TIFF file. 

Figure 7. Open File Dialog 

Click “Open”, if the selected file has an associated XML file, it automatically will be 

loaded (figure 8). Otherwise, the input parameters must be entered as outlined in 

Modifying Input Parameters. 

Figure 8. Loaded Input Parameters 
12 

Next, the output parameters need to be set (figure 9). Again, this procedure is outlined 

in Modifying Output Parameters. This process is streamlined by the “Copy from 

Input” button ( ). If the red output parameters are not visible, click the “Show 

Output Parameters” button ( ).

Figure 9. Edited Output Parameters 

Once all the parameters have been set, click the “Re-project and Save” button ( ), 

choose “File” Æ “Re-project and Save”, or press Ctrl+S. Assuming there are no 

errors or warnings for the parameter choices, the next window shown should be a 

“Save File” dialog (figure 10). This window is used to select the destination and name 

for the new file created after re-projecting. If “.img” is not typed in to the “File 

Name” field then it automatically will be appended. Click “Save” to continue. 

Figure 10. Save File Dialog 
13 

The next window to appear is the “Resample Options” dialog (figure 11). 

Figure 11. Resample Options Dialog 

After clicking “Ok” the re-projection begins. A progress bar (figure 12) is shown, 

which allows the user to abort the process. The re-projection is complete once the 

progress bar reaches 100%. If it reaches this point without the user pressing “Abort” 

then a “Completed” message box will be show (figure 13). 

Figure 12. Re-projection Progress 

Figure 13. Completed Message Box 

By clicking “View Log” the user is shown the MapIMG Log dialog (figure 14), 

which can be used to save the shown log of the re-projection to a text file. 

Figure 14. MapIMG Log Dialog 
14 

Modifying Input Parameters 

The first time a file is loaded, or if the paired XML file becomes corrupt beyond recovery 

the message shown in figure 15 will appear. If a valid XML file was found, the values 

will be loaded. Press the lock/unlock button ( , ) to change to the unlocked state and 

then proceed to change parameters as normal. 

Figure 15. Missing or Corrupt XML 

(1) Setup the “Projection” parameters 

a. Select the “Projection” tab. 

b. Select the projection for the input file from the “Projection” drop down 

menu. 

c. The area below the “Projection” drop down menu will change to reflect 

the parameter relevant to the selected projection. Make all changes 

required to correspond to the input image. This may include “Radius of 

the Reference Sphere”, “Longitude of Central Meridian”, “Latitude of 

True Scale”, “False Easting”, “False Northing”, or other relevant 

parameters. 

(2) Setup the “Map” parameters 

a. Select the “Map” tab. 

b. Select the “Pixel Size” from the “Pixel Size” drop down menu. 

c. Manually enter the number of “Rows of Pixels”, “Columns of Pixels”, 

“Upper-left Latitude in meters”, and “Upper-left Longitude in meters”, or 

press the “Calculate” button ( ) to calculate these parameters based on the 

chosen pixel size and projection.

Note: Currently MapIMG only supports raster datasets of global extent; 

 therefore, calculated values only will be valid if the input is truly to a 

 global extent.

d. Select the pixel data type of the input file from the “Pixel Data Type” drop 

down menu. An incorrect data type will not only produce incorrect results, 

but also may cause instabilities in the MapIMG itself. 

e. If the input image has a frame around it check the “Fill Value” check box

indicating that a “Fill Value” is present. Then, enter the value in the “Fill 

Value” edit box. 

f. If the input image has a value corresponding to areas where data are 

unavailable, check the “No Data Value” check box. Then, enter this value 

in the “No Data Value” edit box. An example of this may be a population 

dataset where areas with an unknown population have a set value, -1 for 

instance. 

g. To save the XML file corresponding to the input image press the 

lock/unlock button ( ) or choose File Æ Save Input Parameters. If the 
15 

lock/unlock button is used the icon should change from unlocked ( ) to 

unlocked ( ) and the parameter fields will become read-only and a 

prompt will ask for confirmation that you want to same the input 

parameters. This indicates a successful save of the XML file. 

Modifying Output Parameters 

Once the desired input file has been loaded and its parameters configured the next step is 

to set up the output projection information. It is suggested that the Copy from Input 

button ( ) is used. This will copy all of the parameters from the input to the output. Once 

this is done, only the parameters to be changed will require user interaction. “Pixel Data 

Type” is set by the input “Pixel Data Type” and cannot be altered. 

(1) Setup the “Projection” parameters 

a. Select the “Projection” tab. 

b. Select the projection that the input file represents from the “Projection” 

drop down menu. Remember to check for the Bad Projection tag (figure 1) 

before continuing. If the tag is present, MapIMG may become unstable or 

produce invalid output if the output projection is used. A link to the 

Decision Support System (DSS) for Map Projections of Small Scale Data 

is provided to assist in selecting an appropriate projection. The link is 

available under “Tools” Æ “Decision Support System”. It will attempt to 

load the default browser of your operating system to the following 

address: http://mcmcweb.er.usgs.gov/DSS/ . 

c. The area below the “Projection” drop down menu will change to reflect 

the parameter relevant to your selected projection. Make all changes 

required to correspond to your input image. This may include “Radius of 

the Reference Sphere”, “Longitude of Central Meridian”, “Latitude of 

True Scale”, “False Easting”, “False Northing”, or other relevant 

parameters. 

d. Make note of any field with an asterisk (*) next to the parameter label. 

These parameters have additional constraints that should be taken into 

account before continuing. Placing the mouse cursor over the label for a 

few seconds will produce a tool-tip with additional information about the 

particular constraints of that parameter. 

(2) Setup the “Map” parameters 

a. Select the “Map” tab. 

b. Select the pixel size from the “Pixel Size” drop down menu. 

c. Press the Calculate button ( ) to calculate “Rows of Pixels”, “Columns of 

Pixels”, “Upper-left Latitude in meters”, and “Upper-left Longitude in 

meters” based on the chosen pixel size and projection.

Note: Calculated values are for a global extent only.

d. If the input image has a “Fill Value” the output “Fill Value” will be the 

same, and may not be changed. This prevents having multiple different 

framing values in the same file. If the input does not have a “Fill Value” it 

can be manually entered or the “Recommend Fill Value” button can be 
16 

pressed to generate a new “Fill Value”. This is done by taking a small 

sample of the image and adding two to the maximum value encountered. 

e. If the input image has a “No Data Value” the output “No Data Value” will 

be the same, and may not be changed. This prevents having multiple 

values indicating where no data are available. If the input does not have a 

“No Data Value” you may check the output “No Data Value” check box 

and manually enter a value in the output “No Data Value” edit box. 

Note: A No Data Value is required if Ignore Values are going to be used 

 during the resample process (see Choosing Resample Options). 

Choosing Resample Options 

After the output file location has been chosen using save and re-project, the next step is to 

choose the resampling options. At any point, the cancel button may be clicked to end the 

re-projection process, and the ok button may be clicked to continue on to the reprojection. 

(1) Choose the resampling method 

The available options currently include “Nearest Neighbor”, “Sum”, 

“Mean”, “Median”, “Mode”, “Min”, and “Max”. As the method is 

selected, text under the choice will change to provide a note on this 

resampling methods performance in categorical vs. continuous data. 

(2) Enter all ignore values into the list 

The ignore values section (figure 16) has, in the upper left, a text box for 

entering values. Once the value is fully typed it can be added to the list by 

clicking “New Value”. Pressing enter while typing in the text box will 

have the same effect. Values can be removed from the list by selecting 

them with the mouse in clicking “Delete Value”. All values entered are 

forced to conform to the pixel data type as defined in the input parameters. 

Figure 16. Ignore Values Section 

(3) Adjust memory allocation 

Allowing for a larger line cache by increasing the memory allocation can 

speed up the re-projection and improve accuracy in the sum resampling. 

This memory is used to store lines of the input image. If a pixel value is 

needed from the input on a line that was accessed before, it would be 

much faster to access it if it was still located in memory; a large line cache 

will improve the chances of that happening. The sum resampling method 
17 

marks pixels in the allocated cache that have been used in the output. If a 

line is pushed out of the cache and then called upon later, the values may 

potentially be counted twice. 

The “Default” value is 100 lines, and the minimum is the ratio of output 

lines to input lines plus 2 percent of the output lines. 

Using the Viewer 

When the viewer is shown with the “Show Preview” button ( ) it will display a USGS 

logo by default. Once an input file has been loaded the viewer will be forced to input 

mode and loading of the preview will begin. This process is completed in two progress 

bars. The first one is creating a color table by sampling the file, and the second one is 

loading values from the file and drawing them into a picture. Once they are both 

complete, the preview image will be displayed. 

The preview panel will stretch to fill the MapIMG window. As the window is resized its 

boundaries will change and the preview picture within will be stretched to maintain the 

original aspect ratio and moved to stay centered in the panel. The image previewed is a 

down-sampled image using nearest neighbor. Therefore, when the image is stretched, the 

individual pixels become larger without resampling the file. Once a new size for the view 

is determined, the “Resample” button ( ) can be clicked and MapIMG will resample the 

file at the current resolution to produce a higher quality image. 

Note that the “Show Preview” button has a down arrow on the lower right corner. 

Clicking and holding on this arrow will show a popup menu allowing the user to switch 

between “Preview Input” and “Preview Output”. Choosing preview output is similar to 

pressing the “Preview Re-projection” button ( ). The preview panel will be displayed 

and four progress bars will complete in the process. The first one represents the downsampling of the original image to a much smaller size. The second one is a fast reprojection to a low resolution version of the output projection parameters. The final two 

progress bars are the color table generation and value loading as outlined previously. 

Other Tools 

Currently, the only extra tool with MapIMG is the Decision Support System for Map 

Projections of Small Scale Data (DSS). A link is available under “Tools” Æ “Decision 

Support System”. It will attempt to load the default browser of your operating system to 

the following address: http://mcmcweb.er.usgs.gov/DSS/ . A user’s guide is available 

for the DSS and is available at http://cartoresearch.er.usgs.gov/projection/pdf/DSS_User_Guide.pdf . 

Troubleshooting 

Error, missing or malformed <___> tag under <___>. 
18 

XML File corrupt or not found. 

These errors occur when there is an issue with the .xml metadata file. The solution is to 

use the input parameter editor and save changes by using the lock button ( ). 

Tiff Image – Conversion failed for unknown reason. 

The Tiff library couldn’t open the chosen Tiff file. Make sure the file pointed to ends in 

.tif and is truly a Tiff image file. 

MapIMG cannot read this file. 

Since MapIMG works with Generic Binary files, the only way of discriminating file 

types is by checking the file’s extension. Make sure the file ends in .img. A common 

error is to use an ERDAS Imagine or Idrisi file, both of which also use the same 

extension of .img. 

Save Input Parameters – File already exists. Do you want to replace it? 

This is a safeguard to protect the metadata file from being replaced if an accidental 

change is made while unlocked. Click “yes” to replace the file with the new parameters 

or “no” to undo all changes and revert the parameters back to how they were last saved. 

MapIMG – Unable to launch web browser to ... 

This error occurs when trying to access the DSS using the Tools menu in MapIMG. The 

solution is to copy and paste the url to your preferred browser. 

 http://mcmcweb.er.usgs.gov/DSS/ 

The current spheroid code and/or unit code are unsupported. 

The spheroid and unit code somehow became modified. This should not be possible with 

the current user interface. 

Pixel Size must be greater than 0. 

Make sure the Pixel Size parameter for the input and output are blank or zero. 

Rows and Columns must be greater than 0. 

These values usually can be generated by the calculator button ( ). If that doesn’t work, 

then you are in either an unsupported “bad projection,” or one of the parameters is set in 

such a way that the final resolution would be very close to zero (ie. True Scale of 

Transverse Mercator shouldn’t be zero). 

Please select a valid data type for each pixel. 

Select a data type using the drop down box in the input parameters. 

If you receive any other errors or unexpected results please contact the authors of 

the MapIMG software package by email at mapimg@usgs.gov. 
19 

References

ERDAS Inc., 1999, ERDAS field guide (5th ed.): Atlanta, Ga. 

Finn, M.P., and Trent, J.R., 2004, Users guide for the MapIMG reprojection software 

package, version 1.01: U.S. Geological Survey Open-File Report 2004-1394. 

Slater, P.N., 1980, Remote sensing - optics and optical systems. Reading, Mass., 

Addison-Wesley Publishing Company, Inc. 

Usery, E.L., Finn, M.P., Cox, J.D., Beard, T., Ruhl, S. and Bearden, M., 2003a, 

Projecting global datasets to achieve equal areas. Cartography and Geographic 

Information Science, v. 30, no. 1., Washington, D.C., ACSM, p. 69-79. 

Usery, E.L., Seong, J.C., Steinwand, D., and Finn, M.P., 2003b, Accurate projection of 

small-scale raster datasets. Proceedings 21st International Cartographic Conference, 

Durban, South Africa. International Cartographic Association.