The purpose of image enhancement is to improve the effect of image interpretation, or convert the image into the format which is suitable for visual observation and machine recognition so as to acquire more useful information.
The system provides general digital enhancement processing functions, it can process images with single band or all bands in one layer at one time. The workflow is explained as follows:
Double click ImageXuite RS.exe in the bin directory of the system installation directory, or double click the shortcut to enter the ImageXuite main interface.
Import the image to be enhanced, there are two methods can be used. Please refer to Data Input for details.
Click the layer in the Layer panel (or channel), the selected layer or channel will be highlighted, as shown in figure.
Click on the layer with right mouse button, point the cursor to the Enhance menu option in the pop-up menu (as shown in figure), then the submenu will appear, as shown in figure.
In which:
None
Display the original image directly without any processing. When the result of enchancement does not satisfy with the expectation, just click this item to delete the processing result, and the original image will be directly displayed.
Linear
Expand or compress the gray range of original images by linear transformation. By default, when open an image, the system will process it with linear enhancement first, that is to say, all the images in image display window are the images after linear enhancement processing instead of original images.
Root
Enhance the image with square root algorithm. Compared to linear enhancement, it will increase the image contrast.
Square
Enhance the image with square algorithm. Compared to linear enhancement, it will reduce the image contrast.
Equalization
Histogram equalization is to ensure that each gray level contains an approximately equal number of pixels, which will enhance the contrast of the images.
LUT Match
The histogram distribution of an image (or ROI) matches to another image. Please refer to Histogram Matching.
After selecting a required enhancement menu option based on the image appearance, the system will process the image automatically and display the results in real time. When the result of enhancement is not satisfied, select None, the system will display the original image directly.
If the image to be processed is in a single channel, just click this channel, it will be highlighted, as shown in figure.
At this time select Histogram property page in the Property panel, it will display the histogram of this image, as shown in figure.
Click Linear button, the submenu will appear, as shown in figure.
The processing function of each menu option corresponds with the corresponding item in figure 3-1-3. Users can select the appropriate enhancement processing based on the requirement, click the corresponding menu option, the system will process the image automatically and display the result in real time, when the result of enhancement is not satisfied, click on None, the system will delete all the processing and display original image directly.
NOTE: if the results for all enhancements do not reach the expectation, users can directly edit its histogram to obtain the satisfied results, please refer to Histogram Editing for details.