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#ifndef BT1886_H
#define BT1886_H
/*
* Author: Graeme W. Gill
* Date: 16/8/13
* Version: 1.00
*
* Copyright 2013, 2014 Graeme W. Gill
* All rights reserved.
*
* This material is licenced under the GNU AFFERO GENERAL PUB LICENSE Version 3 :-
* see the License.txt file for licencing details.
*
*/
/* BT.1886 stype input offset transfer curve, */
/* + general gamma + input + output offset curve support. */
typedef struct {
icmXYZNumber w; /* White point for Lab conversion */
double ingo; /* input Y offset for bt1886 */
double outsc; /* output Y scale for bt1886 */
double outo; /* output Y offset */
double outL; /* output black point L value */
double tab[2]; /* Target ab offset value at zero input for bt1886 */
double gamma; /* bt.1886 technical gamma to apply */
} bt1886_info;
/* Set the bt1886_info to a default do nothing state */
void bt1886_setnop(bt1886_info *p);
/* Setup the bt1886_info for the given target */
void bt1886_setup(
bt1886_info *p,
icmXYZNumber *w, /* wp used for L*a*b* conversion */
double *XYZbp, /* normalised bp used for black offset and black point hue "bend" */
double outoprop, /* 0..1 proportion of output black point compensation */
double gamma, /* technical or effective gamma */
int effg /* nz if effective gamma, z if technical gamma */
);
/* Apply BT.1886 eotf curve to the device RGB value */
/* to produce a linear light RGB. We pass xvYCC out of range values through. */
void bt1886_fwd_curve(bt1886_info *p, double *out, double *in);
/* Apply BT.1886 processing black point hue adjustment to the XYZ value */
void bt1886_wp_adjust(bt1886_info *p, double *out, double *in);
/* Apply inverse BT.1886 eotf curve to the device RGB value */
/* to produce a linear light RGB. We pass xvYCC out of range values through. */
void bt1886_bwd_curve(bt1886_info *p, double *out, double *in);
/* Apply inverse BT.1886 processing black point hue adjustment to the XYZ value */
void bt1886_inv_wp_adjust(bt1886_info *p, double *out, double *in);
#endif /* BT1886_H */
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