static void
vips_Lab2LCh_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
{
float *p = (float *) in[0];
float *q = (float *) out;
int x;
for( x = 0; x < width; x++ ) {
float L = p[0];
float a = p[1];
float b = p[2];
float C, h;
p += 3;
C = sqrt( a * a + b * b );
h = vips_col_ab2h( a, b );
q[0] = L;
q[1] = C;
q[2] = h;
q += 3;
}
}
void
vips_col_ab2Ch( float a, float b, float *C, float *h )
{
#ifdef HAVE_ATAN2
*h = VIPS_DEG( atan2( b, a ) );
if( *h < 0.0 )
*h += 360;
#else
*h = vips_col_ab2h( a, b );
#endif
#ifdef HAVE_HYPOT
*C = hypot( a, b );
#else
*C = sqrt( a * a + b * b );
#endif
}
void
vips_col_ab2Ch( float a, float b, float *C, float *h )
{
*h = vips_col_ab2h( a, b );
*C = sqrt( a * a + b * b );
}
