VXLIB_colorConvert_RGBtoNV12_i8u_o8u

Functions
VXLIB_STATUS	VXLIB_colorConvert_RGBtoNV12_i8u_o8u (const uint8_t src[restrict], const VXLIB_bufParams2D_t *src_addr, uint8_t dst0[restrict], const VXLIB_bufParams2D_t *dst0_addr, uint8_t dst1[restrict], const VXLIB_bufParams2D_t *dst1_addr, uint8_t scratch[restrict], uint32_t scratch_size)
VXLIB_STATUS	VXLIB_colorConvert_RGBtoNV12_i8u_o8u_checkParams (const uint8_t src[], const VXLIB_bufParams2D_t *src_addr, const uint8_t dst0[], const VXLIB_bufParams2D_t *dst0_addr, const uint8_t dst1[], const VXLIB_bufParams2D_t *dst1_addr, const uint8_t scratch[], const uint32_t scratch_size)

Detailed Description

Function Documentation

VXLIB_colorConvert_RGBtoNV12_i8u_o8u()

VXLIB_STATUS VXLIB_colorConvert_RGBtoNV12_i8u_o8u	(	const uint8_t	src[restrict],
		const VXLIB_bufParams2D_t *	src_addr,
		uint8_t	dst0[restrict],
		const VXLIB_bufParams2D_t *	dst0_addr,
		uint8_t	dst1[restrict],
		const VXLIB_bufParams2D_t *	dst1_addr,
		uint8_t	scratch[restrict],
		uint32_t	scratch_size
	)

Description:

Performs a color conversion operation from RGB to NV12.

Method:

Uses 8-bit fixed point approximation of BT.709 coefficients

     Y'=  (( 54*R' + 183*G' + 18*B')+128)/256
     U'=  ((-15*R' -  49*G' + 64*B')+64)/128 + 128
     V'=  (( 64*R' -  58*G' -  6*B')+64)/128 + 128

Parameters

[in]	src[]	Pointer to array containing input RGB image (UQ8.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst0[]	Pointer to array containing output luma plane (UQ8.0)
[in]	dst0_addr[]	Pointer to structure containing dimensional information of dst0
[out]	dst1[]	Pointer to array containing output interleaved UV plane (UQ8.0)
[in]	dst1_addr[]	Pointer to structure containing dimensional information of dst1
[in]	scratch[]	Pointer to array of scratch memory (UQ8.0)
[in]	scratch_size	Parameter indicating the size of scratch memory

Assumptions:

• I/O buffer pointers are assumed to be not aliased.
• RGB Input (1 plane): src_addr
  • 'dim_x' refers to the number of RGB pixel units per line
  • 'dim_y' refers to the number of lines in the image
  • 'stride_y' should be at least ('dim_x' * 3 * 1) bytes
• NV12 (2 planes)
  • dst0_addr
    • 'dim_x' refers to the number of luma pixel units per line
    • 'dim_y' refers to the number of lines in the luma plane
    • 'stride_y' refers to the stride of the luma plane, and should be at least ('dim_x' * 1) bytes
  • dst1_addr
    • 'dim_x' refers to the number of bytes per line (should be equal to dst0_addr.dim_x)
    • 'dim_y' refers to the number of lines in the interleaved chroma plane (should be equal to dst0_addr.dim_y / 2)
    • 'stride_y' refers to the stride of the interleaved chroma plane, and should be at least ('dim_x' * 1) bytes
• Scratch size is equal to at least dst0_addr.dim_x * 4 bytes

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 and width values to a multiple of 8

VXLIB_colorConvert_RGBtoNV12_i8u_o8u_checkParams()

VXLIB_STATUS VXLIB_colorConvert_RGBtoNV12_i8u_o8u_checkParams	(	const uint8_t	src[],
		const VXLIB_bufParams2D_t *	src_addr,
		const uint8_t	dst0[],
		const VXLIB_bufParams2D_t *	dst0_addr,
		const uint8_t	dst1[],
		const VXLIB_bufParams2D_t *	dst1_addr,
		const uint8_t	scratch[],
		const uint32_t	scratch_size
	)

Description:

Checks the parameters for programming errors for the VXLIB_colorConvert_RGBtoNV12_i8u_o8u function.

Method:

The following checks are made:

• There shall be no NULL pointers
• Both images shall have the same x and y dimensions
• The stride_y of the src image shall be equal to or greater than dim_x * 3
• The stride_y of the dst image shall be equal to or greater than dim_x
• scratch_size shall be equal to or greater than dst_addr->stride_y * 4 bytes

Parameters

[in]	src[]	Pointer to array containing input RGB image (UQ8.0)
[in]	src_addr[]	Pointer to structure containing dimensional information of src
[out]	dst0[]	Pointer to array containing output luma plane (UQ8.0)
[in]	dst0_addr[]	Pointer to structure containing dimensional information of dst0
[out]	dst1[]	Pointer to array containing output interleaved UV plane (UQ8.0)
[in]	dst1_addr[]	Pointer to structure containing dimensional information of dst1
[in]	scratch[]	Pointer to array of scratch memory (UQ8.0)
[in]	scratch_size	Parameter indicating the size of scratch memory