VXLIB_convertDepth_i16s_o8u

Functions
VXLIB_STATUS	VXLIB_convertDepth_i16s_o8u (const int16_t src[restrict], const VXLIB_bufParams2D_t *src_addr, uint8_t dst[restrict], const VXLIB_bufParams2D_t *dst_addr, uint32_t shift, uint8_t policy)
VXLIB_STATUS	VXLIB_convertDepth_i16s_o8u_checkParams (const int16_t src[], const VXLIB_bufParams2D_t *src_addr, const uint8_t dst[], const VXLIB_bufParams2D_t *dst_addr, uint32_t shift, uint8_t policy)

Detailed Description

Function Documentation

VXLIB_convertDepth_i16s_o8u()

VXLIB_STATUS VXLIB_convertDepth_i16s_o8u	(	const int16_t	src[restrict],
		const VXLIB_bufParams2D_t *	src_addr,
		uint8_t	dst[restrict],
		const VXLIB_bufParams2D_t *	dst_addr,
		uint32_t	shift,
		uint8_t	policy
	)

Description:

Converts image bit depth.

Method:

Convert Bit Depth is computed by using the following equation:

 For Wrap Policy:
 dst(x,y) = ((uint8)(src(x,y) >> shift));

 For Saturate Policy:
 int16 value = src(x,y) >> shift;
 value = value < 0 ? 0 : value;
 value = value > 255 ? 255 : value;
 dst(x,y) = (uint8)value;

Parameters

[in]	src[]	Pointer to array containing first input image (SQ15.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst[]	Pointer to array containing output image (UQ8.0)
[in]	dst_addr[]	Pointer to structure containing dimensional information of dst
[in]	shift	Parameter indicating shift value; valid for 0 <= shift < 8
[in]	policy	Parameter indicating overflow policy

Assumptions:

• I/O buffer pointers are assumed to be not aliased.

Performance Considerations:

• For best performance, the following parameter settings are recommended:
  • Set widths equal to strides
  • Align all pointers to 8 byte boundaries
  • Set all stride values to a multiple of 8
  • Set all width values to a multiple of 16

VXLIB_convertDepth_i16s_o8u_checkParams()

VXLIB_STATUS VXLIB_convertDepth_i16s_o8u_checkParams	(	const int16_t	src[],
		const VXLIB_bufParams2D_t *	src_addr,
		const uint8_t	dst[],
		const VXLIB_bufParams2D_t *	dst_addr,
		uint32_t	shift,
		uint8_t	policy
	)

Description:

Checks the parameters for programming errors for the VXLIB_convertDepth_i16s_o8u function.

Method:

The following checks are made:

• There shall be no NULL pointers
• All images shall have the same x and y dimensions
• The strides of each image shall be equal to or greater than the x dimension
• 'shift' value shall conform to range: 0 <= shift < 8
• The policy is either VXLIB_CONVERT_POLICY_WRAP or VXLIB_CONVERT_POLICY_SATURATE

Parameters

[in]	src[]	Pointer to array containing first input image (SQ15.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst[]	Pointer to array containing output image (UQ8.0)
[in]	dst_addr[]	Pointer to structure containing dimensional information of dst
[in]	shift	Parameter indicating shift value; valid for 0 <= shift < 8
[in]	policy	Parameter indicating overflow policy