Convert to Black and White
Click the Image | Processing Filters | Convert to Black and White command to convert color images to black and white. This feature is useful when the file size is very large. Converting the image to black and white reduces the memory overhead and allows the program to process information more quickly.
Set the Method and click OK to convert the color image to black and white.
The Method determines how the colors are converted to black and white. Available options are: Intensity Threshold and Brightness Threshold. To change the Method, click on the existing option and select the desired option from the list. Intensity Threshold refers to the magnitude, or amount, of light actually reflected or transmitted. For instance, a low Intensity Threshold yields more white in the image and a high Intensity Threshold yields more black. Brightness Threshold refers to the contrast of brightness between black and white. For instance, a low Brightness Threshold makes more black pixels white. A high Brightness Threshold creates a higher brightness contrast by making more white pixels black.
To change the amount of the method applied, click and drag the 
to the desired value.
The immediate effects of the method options are displayed in the dialog. The image on the left side is the Original Image, as it appears in the project. The image on the right is the Sample Output, which displays the changes as the Method and amount of the Method are changed in the dialog.
Above the image are several buttons for zooming in or out on the image. Click the 
button to enter zoom in mode. The cursor changes to 
to indicate zoom in mode. Click on the image to zoom in at the desired location. Click the 
button to the left of the image to enter zoom out mode. The cursor changes to 
to indicate zoom out mode. Click on the image to zoom out at the desired location.
Click the 
button to zoom out to the entire extents of the image. The full image is displayed.
Click the 
button to enter pan mode. Click and hold the mouse button down. The cursor changes to 
to indicate pan mode. Drag the mouse around to move the image. Alternatively, click and hold the mouse wheel down to pan around the image.
As the zoom changes in the Original Image view, the same zoom appears in the Sample Output view. This way you can compare the same extents with the applied settings in both views.
Click OK to apply the black and white method to the image. Click Cancel to close the dialog without applying the black and white method to the image.
See Also