Image Registration Dialog

(This functionality is available with the Background Images module)

Used to select which image transformation method to use, set the control points, clip the image and create the transformed registered image.

The Image Registration dialog is available when the Image Registrar window is opened from the Registration / Import and Register Image or Check Image Registration commands from the Background Images task.

For information on how to perform an image registration refer to the topic "The Image Registration Process".

To gain a better understanding of image registration and when to use the different transformation types refer to the topic "Background Image Concepts".

Import and Register Image dialog box

Item	Used to
Image Name:	Displays the name of the transformed image inside the LISCAD data base.
Image File:	Displays the folder and name of the original file that is to be transformed and imported into the LISCAD data base.
Browse:	Press the Browse button to locate or change the original image that you wish to register.
Transformation Type:	Select the type of transformation that is to be performed on the image. You can select from Conformal, Affine, 2nd Order Polynomial or 3rd Order Polynomial. For details on which image transformation type to use under what circumstances refer to the Background Image Concepts.
Bring To Front:	If checked the resultant transformed image will be brought to the top of the display list making sure that the whole image can be viewed and the registration verified.
Compression Factor:	If checked the resultant transformed image will be brought to the top of the display list making sure that the whole image can be viewed and the registration verified. :Enter an number between 1 and 100. The smaller the number the less the compression, resulting in better detail but a larger image file. The larger the number the greater the compression, resulting in loss of detail but a smaller image file. A default value of 10.0 is set as this generally gives a good compromise between loss of detail and image size. If the original image is in a format that is loss full, e.g. JPG, MrSID or ECW, then it is wise to keep the compression factor low otherwise you will be compressing an already compressed image which can result in further degradation of the original. Likewise if the image is of a map which is predominantly line work as opposed to a photographic image, compression can be more noticeable as it can introduce ghosting around the lines. Control Mode Select the Control radio button if you wish to add or edit registration control points.
Clip Mode:	Select the Clip mode radio button if you wish to clip the image. For details on how to enter the control co-ordinates, clip the image and perform the registration refer to the topic "The Image Registration Process".
Grid Control:	Used to enter the image and real world control co-ordinates. Also displays the computed residuals. This control is only active when the Control Mode radio button is selected. Compute Residuals This button will compute and update the control point residuals. You must have entered at least the minimum number of control points for the type of transformation you are performing.
Register Image:	Performs the image transformation to register it with the data base. This results in a new transformed image being created and stored internally in the LISCAD data base. If the transformation is successful the transformed image will be displayed in the Plan View so that the registration can be verified against the data base.
Save:	Saves the current configuration settings under the image name without performing the registration and transformation. This allows the registration process to be closed before all the relevant registration data has been entered. If the image has been previously registered and you make changes in the registration dialog, pressing the Save button will delete the currently registered image and it will no longer be displayed. This is because the registered image no longer accords with the registration data. To be able to view the image again the registration process will have to be completed later. To continue the image registration process at a later stage go to Background Images / Registration / Check Image Registration and selecting the image name.
Close:	Closes the Image Registration dialog and the Image Registrar window. If registration information has been edited but not saved the system will prompt to see if the changes are to be saved or the editing is to be cancelled. Closing the Image Registrar window is equivalent to pressing the Close button on the Image Registration dialog.