VXLIB_sobelX_3x3_i8u_o16s

Functions
VXLIB_STATUS	VXLIB_sobelX_3x3_i8u_o16s (const uint8_t src[restrict], const VXLIB_bufParams2D_t *src_addr, int16_t dst[restrict], const VXLIB_bufParams2D_t *dst_addr)
VXLIB_STATUS	VXLIB_sobelX_3x3_i8u_o16s_checkParams (const uint8_t src[restrict], const VXLIB_bufParams2D_t *src_addr, const int16_t dst[restrict], const VXLIB_bufParams2D_t *dst_addr)

Detailed Description

Function Documentation

VXLIB_sobelX_3x3_i8u_o16s()

VXLIB_STATUS VXLIB_sobelX_3x3_i8u_o16s	(	const uint8_t	src[restrict],
		const VXLIB_bufParams2D_t *	src_addr,
		int16_t	dst[restrict],
		const VXLIB_bufParams2D_t *	dst_addr
	)

Description:

Computes the sobel image filter kernel over a 3x3 window of imput image, for each pixel.

Method:

Produces only the X output plane in a single pass through the image. The sobel X operator is defined as:

       | -1 0 +1 |
 Gx =  | -2 0 +2 |
       | -1 0 +1 |

Parameters

[in]	src[]	Pointer to array containing input image (UQ8.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst[]	Pointer to array containing output image (SQ15.0)
[in]	dst_addr[]	Pointer to structure containing dimensional information of dst

Assumptions:

• I/O buffer pointers are assumed to be not aliased.
• Output height should be == (Input height - 2)
• Output width should be == (Input width - 2) OR (Input width)

Performance Considerations:

• For best performance, the following parameter settings are recommended:
  • Set output width values to a multiple of 8
  • Set widths equal to each other and equal to strides (allows processing over whole image in single loop)
  • If both x and y gradients are needed instead of only X, one should use VXLIB_sobel_3x3_i8u_o16s_o16s.

VXLIB_sobelX_3x3_i8u_o16s_checkParams()

VXLIB_STATUS VXLIB_sobelX_3x3_i8u_o16s_checkParams	(	const uint8_t	src[restrict],
		const VXLIB_bufParams2D_t *	src_addr,
		const int16_t	dst[restrict],
		const VXLIB_bufParams2D_t *	dst_addr
	)

Description:

Checks the parameters for programming errors for the VXLIB_sobelX_3x3_i8u_o16s function.

Method:

The following checks are made:

• There shall be no NULL pointers
• Output height should be == (Input height - 2)
• Output width should be <= Input width
• The strides of each image shall be equal to or greater than the x dimension

Parameters

[in]	src[]	Pointer to array containing input image (UQ8.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst[]	Pointer to array containing output image (SQ15.0)
[in]	dst_addr[]	Pointer to structure containing dimensional information of dst