TYPE: COP
TITLE: Contrast COP

This operation increases or decreases the contrast of an image.

Middle click on the dialog '?' help for more help on maskable pixel operations.

Parameters
Contrast page:
    Range / Scale      - Two different methods to apply contrast.
	Range - Contrast is increased by narrowing the range, and 
		decreased by widening it. This method maps black and
		white to the new range values.
	Scale - Contrast is determined by a contrast factor and center.
		Increasing the contrast parm increases overall contrast
		by scaling the range about the contrast center,
		normally 50% grey.
	Notes - The two methods attempt to be consistent with one another,
		however, the Range method can represent a wider variety of
		color transformations once the range moves outside 0 to 1.
		In this case, switching back to Scale may change the
		results.

		Each method provides a global setting and a component
		setting.  The global contrast is applied first, and then
		the component contrast. The contrast is still done in one
		pass.

Quantize, Mask & Plane Scope, Frame Scope page:
    Overview - See extra help (Middle click on the dialog '?' help).

Local Variables:
    L   - Sequence length
    S   - Start of sequence
    E   - End of sequence
    IL  - Input sequence length
    SR  - Sequence frame rate
    NP  - Number of planes in sequence
    W,H - Width and height of image
    I   - Image index (0 at start frame)
    IT  - Image time (0 at start frame)
    AI  - Current plane array index
    PI  - Current plane index
    PC  - Num of channels in current plane

See Also: Bright, Equalize, Gamma, Quantize 
