HighlightImage

highlights the specified region of interest roi in image.

HighlightImage[image,{roi₁,roi₂,…}]

highlights several regions of interest roi_i.

HighlightImage[image,{…,w[roi_i],…}]

adds a feature defined by the symbolic wrapper w.

HighlightImage[image,fg,bgstyle]

applies the styling bgstyle to the complement of all the regions of interest.

Details and Options

HighlightImage is used for highlighting particular regions or features in an image. It returns the highlighted image as a Graphics object.
The region of interest roi can be any of the following:

	{{x₁,y₁},…}	a list of image positions
	region	a 2D geometric region (Point, Line, Disk, etc)
	maskimage	non-zero pixels of an Image object
	graphics	a Graphics object
	f	a region returned by a function f

By default, using DataRange->Full, positions {x_i,y_i} and geometric regions are assumed to be in the standard image coordinate system.
Basic style specifications include:

	Automatic	automatically select the highlighting method
	color	color specification (RGBColor, LABColor, etc.)
	directive	any valid graphics directive (PointSize, Thickness, etc.)

	Annotation[e,label]	provide an annotation
	Button[e,action]	define an action to execute when the element is clicked
	EventHandler[e,…]	define a general event handler for the element
	Hyperlink[e,uri]	make the element act as a hyperlink
	ImageMarker[e,…]	an image marker, placing a marker at the medoid of e
	PopupWindow[e,cont]	attach a popup window to the element
	StatusArea[e,label]	display in the status area when the element is moused over
	Style[e,opts]	show the element using the specified styles
	Tooltip[e,label]	attach an arbitrary tooltip to the element

Additional style specifications include:
"Blur",{"Blur",r} blur using range r neighborhoods

"Boundary",{"Boundary",t} highlight the boundary using thickness t
Nested lists of regions-of-interest and styles can be given. Style specifications remain in effect only until the end of the list that contains them.
The background is taken to be the complement of all regions of interest. The following bgstyle specifications can be used:

		"Blur", {"Blur",r}	blur using range r neighborhoods
		"Darken",{"Darken",a}	blend with black (default )
		"Lighten",{"Lighten",a}	blend with white (default )
		"Desaturate",{"Desaturate",s}	desaturate
		"Remove"	make background transparent
		{"Remove",color}	replace background with color
		f	perform f on the background

HighlightImage accepts all Graphics options with the following changes and additions:

DataRange	Full	range of coordinates in the original image
PlotRange	Automatic	range of coordinates to include
PlotRangePadding	None	how much to pad the range of values

Typical settings for DataRange include:
Automatic {{0,1},{0,h/w}}

Full {{0,w},{0,h}}

{{left,right},{bottom,top}} explicit coordinate ranges in 2D
Typical settings for PlotRange include:
All all points are included

Automatic same as DataRange settings

{{left,right},{bottom,top}} explicit coordinate ranges