/**
* im_col_dECMC:
* @L1: Input coordinate 1
* @a1: Input coordinate 1
* @b1: Input coordinate 1
* @L2: Input coordinate 2
* @a2: Input coordinate 2
* @b2: Input coordinate 2
*
* CMC colour difference from a pair of Lab values.
*
* Returns: CMC(1:1) colour difference
*/
float
im_col_dECMC( float L1, float a1, float b1,
float L2, float a2, float b2 )
{
float h1, C1;
float h2, C2;
float Lucs1, Cucs1, hucs1;
float Lucs2, Cucs2, hucs2;
float aucs1, bucs1;
float aucs2, bucs2;
/* Turn to LCh.
*/
im_col_ab2Ch( a1, b1, &C1, &h1 );
im_col_ab2Ch( a2, b2, &C2, &h2 );
/* Turn to LCh in CMC space.
*/
Lucs1 = im_col_L2Lucs( L1 );
Cucs1 = im_col_C2Cucs( C1 );
hucs1 = im_col_Ch2hucs( C1, h1 );
Lucs2 = im_col_L2Lucs( L2 );
Cucs2 = im_col_C2Cucs( C2 );
hucs2 = im_col_Ch2hucs( C2, h2 );
/* Turn to Lab in CMC space.
*/
im_col_Ch2ab( Cucs1, hucs1, &aucs1, &bucs1 );
im_col_Ch2ab( Cucs2, hucs2, &aucs2, &bucs2 );
/* Find difference.
*/
return( im_col_pythagoras( Lucs1, aucs1, bucs1, Lucs2, aucs2, bucs2 ) );
}
/* Our main loop.
*/
void
imb_LCh2UCS( float *p, float *q, int n )
{
int x;
for( x = 0; x < n; x++ ) {
float L = p[0];
float C = p[1];
float h = p[2];
p += 3;
/* Turn to UCS.
*/
q[0] = im_col_L2Lucs( L );
q[1] = im_col_C2Cucs( C );
q[2] = im_col_Ch2hucs( C, h );
q += 3;
}
}
