canny

Canny Edge Detector. More...

Functions
AFAPI array	canny (const array &in, const cannyThreshold thresholdType, const float lowThresholdRatio, const float highThresholdRatio, const unsigned sobelWindow=3, const bool isFast=false)
	C++ Interface for canny edge detector. More...
AFAPI af_err	af_canny (af_array *out, const af_array in, const af_canny_threshold threshold_type, const float low_threshold_ratio, const float high_threshold_ratio, const unsigned sobel_window, const bool is_fast)
	C Interface for canny edge detector. More...

Detailed Description

Canny Edge Detector.

The Canny edge detector is an edge detection operator that uses a multi-stage algorithm to detect a wide range of edges in images. A more in depth discussion on it can be found here.

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Function Documentation

af_canny()

AFAPI af_err af_canny	(	af_array *	out,
		const af_array	in,
		const af_canny_threshold	threshold_type,
		const float	low_threshold_ratio,
		const float	high_threshold_ratio,
		const unsigned	sobel_window,
		const bool	is_fast
	)

C Interface for canny edge detector.

Parameters

[out]	out	is an binary array containing edges
[in]	in	is the input image
[in]	threshold_type	determines if user set high threshold is to be used or not. It can take values defined by the enum af_canny_threshold
[in]	low_threshold_ratio	is the lower threshold % of the maximum or auto-derived high threshold
[in]	high_threshold_ratio	is the higher threshold % of maximum value in gradient image used in hysteresis procedure. This value is ignored if AF_CANNY_THRESHOLD_AUTO_OTSU is chosen as af_canny_threshold
[in]	sobel_window	is the window size of sobel kernel for computing gradient direction and magnitude
[in]	is_fast	indicates if L1 norm(faster but less accurate) is used to compute image gradient magnitude instead of L2 norm.

Returns

AF_SUCCESS if the moment calculation is successful, otherwise an appropriate error code is returned.

canny()

AFAPI array canny	(	const array &	in,
		const cannyThreshold	thresholdType,
		const float	lowThresholdRatio,
		const float	highThresholdRatio,
		const unsigned	sobelWindow = 3,
		const bool	isFast = false
	)

C++ Interface for canny edge detector.

Parameters

[in]	in	is the input image
[in]	thresholdType	determines if user set high threshold is to be used or not. It can take values defined by the enum af_canny_threshold
[in]	lowThresholdRatio	is the lower threshold % of maximum or auto-derived high threshold
[in]	highThresholdRatio	is the higher threshold % of maximum value in gradient image used in hysteresis procedure. This value is ignored if AF_CANNY_THRESHOLD_AUTO_OTSU is chosen as af_canny_threshold
[in]	sobelWindow	is the window size of sobel kernel for computing gradient direction and magnitude
[in]	isFast	indicates if L1 norm(faster but less accurate) is used to compute image gradient magnitude instead of L2 norm.

Returns

binary array containing edges