Projection objects are used in various ways for image or field analysis, as shown in the following examples. Let us choose now a color image as input, 'UVMAT_DEMO_FILES/EX02_color/images/frame1.jpg'. We notice in this example that the frame index '1' directly follows the [RootFile] 'frame' (without separator '_'), so [NomType?] is '1'. By moving the mouse over the image, we notice that the luminosoty A has thre components, corresponding to the color components rgb (red, green, blue). Similarly the histogram has three curves.

Plotting a luminosity profile

Create a line by the menu bar command 'Projection Object/line'. A new GUI 'set_object' appears on the right side, with default settings Type='line', ProjMode?='projection'. Draw a line with the mouse, left hande side button to mark the beginning and end of the line. The luminosity profile, with the three rgb components, appears in a new GUI 'view_field'. The line can be moved with the mouse, or by introducing the ccordanates of the line in the table [Coord] of the GUI set_object.

Getting the image histogram in a sub-region

Resampling the image