This effect applies an edge detection convolution to a single source. The performance of the edge detection is determined by the convolution kernel. This is a matrix of values applied to each pixel of the source to produce the resulting image.
This effect takes a maximum of one source.
The QTPlgEffectEdgeDetectionDesc class implements methods and properties to setup programmatically the parameters of the edge detection effect provided natively by QuickTime.
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The QTPlgEffectEdgeDetectionDesc class constructors are called when you create a new instance of the class, while the ˜QTPlgEffectEdgeDetectionDesc class destructor, is called automatically when the class is no more in use. Also, you can invoke the class destructor by setting the instance of the class to nil.
Once a new class instance is returned, it is good practice to check the class property to be sure that the new object can be used. For discussion about the validity of an effect description instance see the documentation relative to the .
The class provides you with the following initializer methods:
()
This is the default constructor. Use this constructor to create a completely new data descriptor container in memory.
(other as )
This is the copy constructor. The properties of the object to be copied will be used to initialize the
new class instance properties. Note that the parameter passed is a generic object; this is due to the
fact that you could use a descriptor obtained by the that returns a generic
. Anyway, the class makes a
control to check if the passed object is suitable for use and, if not, will initialize the class instance with default values
specifies the size of the kernel to apply. This value must be one of 3, 5, 7,
9, 11, 13 or 15. Larger kernels will produce thicker edges in the resulting image
if this property is set to true, the color of the edges produced by the effect are based on the color of the source pixels around them.
Otherwise, edges are rendered as light grey against a dark grey background