pictures/imod_logo.png

iMOD User Manual version 5.2 (html)


5.3Add Background Image

This functionality will offer the possibility to use your own background images instead of the one defined by the keyword TOP25 in the selected *.PRF-file. On the menubar click View and then choose the option Add Background Image to open the corresponding window.

Add Background Image window:

pictures/h1-h3/image141.png

Add ...

Click this button to add a *.BMP or *.png file to the menu list of Existing BMPs. You are able to load all kinds of images, e.g. aerial photograph, satellite images (obtained by Google Earth). The PNG format is preferable to BMPs since it is significant smaller in size.

Delete Selected
Files from List ...

Click this button to delete the selected file from the menu list of Existing BMPs.

Columns

Number of columns in the image

Rows

Number of row in the image

XLLC (km)

Enter the x-coordinate of the lower-left-corner (south-west) of the image.

YLLC (km)

Enter the y-coordinate of the lower-left-corner (south-west) of the image.

XURC (km)

Displays the x-coordinate of the upper-right-corner (north-east) of the image that will be computed from the XLLC and the bitmap width.

YURC (km)

Displays the y-coordinate of the upper-right-corner (north-east) of the image that will be computed from the YLLC and the bitmap height.

Size dX (m)

Bitmap width.

Size dY (m)

Bitmap height which will be equal to Size dX, automatically.

Apply

Click this button to show the background map. It also closes the Add Background Image window. The images (can be more than one) in the list of Existing BMPs will be shown when the menu option Show Background Image from the View menu is checked or when the corresponding icon from the tool bar is checked.

Close

Click this button to close the Add Background Image window.

Help …

Click this button to start the iMOD Help Functionality (if available in the selected *.PRF file).

Note: To reference the image topographically you can either enter the position of the image or add a so called worldfile in the same directory as the loaded image. iMOD will search for {ext}W files, e.g. BMPW/BPW, PNGW/PGW, JPGW/JGW or PCXW/PXW to read the information. The following information is listed in a worldfile.

Dx

Rastersize (m) x-direction (west-east).

RotX

Value of rotation along the y-axis, RotX=0 for correct usage in iMOD.

RotY

Value of rotation along the x-axis, RotY=0 for correct usage in iMOD.

Dy

Rastersize (m) in the y-direction, it should be a negative number, since it is measured from north to south. For correct usage in iMOD Dx=-Dy.

XULC

X-coordinate (m) for the center of the upper-left-corner (north-west).

YULC

Y-coordinate (m) for the center of the upper-left-corner (north-west).

Example of a worldfile:

20.17541308822119
0.00000000000000
0.00000000000000
-20.17541308822119
424178.11472601280548
4313415.90726399607956

Example of usage of a bitmap loaded via the option Add Background Image:

pictures/h1-h3/image143.png