This submenu provides a method for approximating the variations in the background illumination by a simple polynomial. Up to 13 coefficients may be fitted by a Least Squares fit onto up to 2048 blocks within a user defined window.
NOTE: The coefficients evaluated in this submenu will be lost if control is passed over to another DigImage module. If you wish to retain the coefficients, you must save them using [S Save to file] before leaving this menu. They may be restored later with [R Restore from file].
Once a polynomial has been fitted to the intensity field within a buffer, the polynomial may be calculated and displayed in a specified window within a specified buffer by means of this option.
This option fits a polynomial to the intensity field within a specified window in a given buffer. A submenu allows choice between a number of different functions (linear in the unknown coefficients) to be fitted.
The coefficients evaluated by [F Fit polynomial to image] may be stored in a formatted file by [S Save to file]. This option allows the coefficients to be reloaded from such a file.
S This option allows the coefficients evaluated by [F Fit polynomial to background] to be stored in a formatted file. These coefficients may be reloaded subsequently by [R Restore from file] if desired.
DigImage User Documentation