NVIDIA 2D Image And Signal Performance Primitives (NPP)  Version 11.3.0.*
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Functions

RGB to PhotoYCC color conversion. More...

Functions

NppStatus  nppiRGBToYCC_8u_C3R_Ctx (const Npp8u *pSrc, int nSrcStep, Npp8u *pDst, int nDstStep, NppiSize oSizeROI, NppStreamContext nppStreamCtx)
  3 channel 8-bit unsigned packed RGB to 3 channel 8-bit unsigned packed YCC color conversion. More...
 
NppStatus  nppiRGBToYCC_8u_C3R (const Npp8u *pSrc, int nSrcStep, Npp8u *pDst, int nDstStep, NppiSize oSizeROI)
 
NppStatus  nppiRGBToYCC_8u_AC4R_Ctx (const Npp8u *pSrc, int nSrcStep, Npp8u *pDst, int nDstStep, NppiSize oSizeROI, NppStreamContext nppStreamCtx)
  4 channel 8-bit unsigned packed RGB with alpha to 4 channel 8-bit unsigned packed YCC with alpha color conversion. More...
 
NppStatus  nppiRGBToYCC_8u_AC4R (const Npp8u *pSrc, int nSrcStep, Npp8u *pDst, int nDstStep, NppiSize oSizeROI)
 

Detailed Description

RGB to PhotoYCC color conversion.

This is how NPP converts gamma corrected BGR or RGB to PhotoYCC. The computed Y, C1, C2 values are then quantized and converted to fit in the range [0..1] before expanding to 8 bits.

* Npp32f nNormalizedR = (Npp32f)R * 0.003921569F; // / 255.0F
* Npp32f nNormalizedG = (Npp32f)G * 0.003921569F;
* Npp32f nNormalizedB = (Npp32f)B * 0.003921569F;
* Npp32f nY = 0.299F * nNormalizedR + 0.587F * nNormalizedG + 0.114F * nNormalizedB;
* Npp32f nC1 = nNormalizedB - nY;
* nC1 = 111.4F * 0.003921569F * nC1 + 156.0F * 0.003921569F;
* Npp32f nC2 = nNormalizedR - nY;
* nC2 = 135.64F * 0.003921569F * nC2 + 137.0F * 0.003921569F;
* nY = 1.0F * 0.713267F * nY; // / 1.402F
* Y = (Npp8u)(nY * 255.0F);
* C1 = (Npp8u)(nC1 * 255.0F);
* C2 = (Npp8u)(nC2 * 255.0F);
*

Function Documentation

NppStatus nppiRGBToYCC_8u_AC4R ( const Npp8u pSrc,
int  nSrcStep,
Npp8u pDst,
int  nDstStep,
NppiSize  oSizeROI 
)
NppStatus nppiRGBToYCC_8u_AC4R_Ctx ( const Npp8u pSrc,
int  nSrcStep,
Npp8u pDst,
int  nDstStep,
NppiSize  oSizeROI,
NppStreamContext  nppStreamCtx 
)

4 channel 8-bit unsigned packed RGB with alpha to 4 channel 8-bit unsigned packed YCC with alpha color conversion.

Parameters
pSrc Source-Image Pointer.
nSrcStep Source-Image Line Step.
pDst Destination-Image Pointer.
nDstStep Destination-Image Line Step.
oSizeROI Region-of-Interest (ROI).
nppStreamCtx Application Managed Stream Context.
Returns
Image Data Related Error Codes, ROI Related Error Codes
NppStatus nppiRGBToYCC_8u_C3R ( const Npp8u pSrc,
int  nSrcStep,
Npp8u pDst,
int  nDstStep,
NppiSize  oSizeROI 
)
NppStatus nppiRGBToYCC_8u_C3R_Ctx ( const Npp8u pSrc,
int  nSrcStep,
Npp8u pDst,
int  nDstStep,
NppiSize  oSizeROI,
NppStreamContext  nppStreamCtx 
)

3 channel 8-bit unsigned packed RGB to 3 channel 8-bit unsigned packed YCC color conversion.

Parameters
pSrc Source-Image Pointer.
nSrcStep Source-Image Line Step.
pDst Destination-Image Pointer.
nDstStep Destination-Image Line Step.
oSizeROI Region-of-Interest (ROI).
nppStreamCtx Application Managed Stream Context.
Returns
Image Data Related Error Codes, ROI Related Error Codes