HLSToBGR

Convert from HLS to BGR

Supported Technologies

MT

Synopsis

FwStatus   fwiHLSToBGR_8u_C3P3R ( const Fw8u * pSrc, int srcStep, Fw8u * const pDst[3], int dstStep, FwiSize roiSize );
FwStatus   fwiHLSToBGR_8u_AC4P4R ( const Fw8u * pSrc, int srcStep, Fw8u * const pDst[4], int dstStep, FwiSize roiSize );
FwStatus   fwiHLSToBGR_8u_AP4R ( const Fw8u * const pSrc[4], int srcStep, Fw8u * const pDst[4], int dstStep, FwiSize roiSize );
FwStatus   fwiHLSToBGR_8u_P3R ( const Fw8u * const pSrc[3], int srcStep, Fw8u * const pDst[3], int dstStep, FwiSize roiSize );
FwStatus   fwiHLSToBGR_8u_AP4C4R ( const Fw8u * const pSrc[4], int srcStep, Fw8u * pDst, int dstStep, FwiSize roiSize );
FwStatus   fwiHLSToBGR_8u_P3C3R ( const Fw8u * const pSrc[3], int srcStep, Fw8u * pDst, int dstStep, FwiSize roiSize );

Parameters

dstStep   Destination buffer step size (width of the buffer in bytes).
pDst   Pointer to a location in a destination buffer.
pDst[3]   Pointer to a location in a three-channel planar destination buffer (array values point to a location in each plane).
pDst[4]   Pointer to a location in a four-channel planar destination buffer (array values point to a location in each plane).
pSrc   Pointer to a location in a source buffer.
pSrc[3]   Pointer to a location in a three-channel planar source buffer (array values point to a location in each plane).
pSrc[4]   Pointer to a location in a four-channel planar source buffer (array values point to a location in each plane).
roiSize   Specifies the height and width of an ROI.
srcStep   Source buffer step size (width of the buffer in bytes).

Description

These functions step through an ROI in a source buffer, convert the source data from the HLS color space to the BGR color model, and write the converted data to a destination buffer.

An HLS image (pSrc) declared in the ROI is converted to a gamma-corrected RGB image (pDst) as follows. 

if ( L <= 0.5)
 M2 = L * (1+S)
else
 M2 = L + S - L*S
 M1 = 2*L - M2
if (S == 0)
 R = G = B = L
else
{
 h = H + 120
 if (h > 360)
  h = h - 360
 if (h < 60)
  R = (M1 + (M2 - M1)*h/60)
 else if (h < 180)
  R = M2
 else if (h < 240)
  R = M1 + (M2 - M1)*(240 - h)/60
 else
  R = M1
  h = H
 if (h < 60)
  G = (M1 + (M2 - M1)*h/60)
 else if (h < 180)
  G = M2
 else if (h < 240)
  G = M1 + (M2 - M1)*(240 - h)/60
 else
  G = M1
  h = H - 120
 if (h < 60)
  B = (M1 + (M2 - M1)*h/60)
 else if (h < 180)
  B = M2
 else if (h < 240)
  B = M1 + (M2 - M1)*(240 - h)/60
 else
  B = M1
}

The formulas assume that H, L, and S values are in the range [0 to 1].
For integer destination data type, the values are scaled to the full range of the data type.