Magnitude

Detailed Description

Implements the Gradient Magnitude Computation Kernel.

This kernel takes two gradients in VX_DF_IMAGE_S16 format and computes the VX_DF_IMAGE_S16 normalized magnitude. Magnitude is computed as:

\[ mag(x,y) = \sqrt{grad_x(x,y)^2 + grad_y(x,y)^2} \]

The conceptual definition describing the overflow is given as: uint16 z = uint16( sqrt( double( uint32( int32(x) * int32(x) ) + uint32( int32(y) * int32(y) ) ) ) ); int16 r = z > 32767 ? 32767 : z;

Functions
vx_node	vxMagnitudeNode (vx_graph graph, vx_image grad_x, vx_image grad_y, vx_image mag)
	[Graph] Create a Magnitude node. More...
vx_status	vxuMagnitude (vx_context context, vx_image grad_x, vx_image grad_y, vx_image output)
	[Immediate] Invokes an immediate Magnitude. More...

Function Documentation

vx_node vxMagnitudeNode	(	vx_graph	graph,
		vx_image	grad_x,
		vx_image	grad_y,
		vx_image	mag
	)

[Graph] Create a Magnitude node.

Parameters

[in]	graph	The reference to the graph.
[in]	grad_x	The input x image. This must be in VX_DF_IMAGE_S16 format.
[in]	grad_y	The input y image. This must be in VX_DF_IMAGE_S16 format.
[out]	mag	The magnitude image. This is in VX_DF_IMAGE_S16 format.

See also

VX_KERNEL_MAGNITUDE

Returns

vx_node.

Return values

0	Node could not be created.
*	Node handle.

vx_status vxuMagnitude	(	vx_context	context,
		vx_image	grad_x,
		vx_image	grad_y,
		vx_image	output
	)

[Immediate] Invokes an immediate Magnitude.

Parameters

[in]	context	The reference to the overall context.
[in]	grad_x	The input x image. This must be in VX_DF_IMAGE_S16 format.
[in]	grad_y	The input y image. This must be in VX_DF_IMAGE_S16 format.
[out]	output	The magnitude image. This will be in VX_DF_IMAGE_S16 format.

Returns

A vx_status_e enumeration.

Return values

VX_SUCCESS	Success
*	An error occurred. See vx_status_e.