diff options
Diffstat (limited to 'xicc/cam02ref.h')
| -rw-r--r-- | xicc/cam02ref.h | 60 |
1 files changed, 37 insertions, 23 deletions
diff --git a/xicc/cam02ref.h b/xicc/cam02ref.h index de75f6b..8965b7a 100644 --- a/xicc/cam02ref.h +++ b/xicc/cam02ref.h @@ -41,7 +41,8 @@ struct _cam02ref { double Lv, /* Luminance of white in the Viewing/Scene/Image field (cd/m^2) */ /* Ignored if Ev is set */ double Yf, /* Flare as a fraction of the reference white (range 0.0 .. 1.0) */ - double Fxyz[3], /* The Flare white coordinates (typically the Ambient color) */ + double Yg, /* Glare as a fraction of the ambient (range 0.0 .. 1.0) */ + double Gxyz[3], /* The Glare white coordinates (typically the Ambient color) */ int hk /* Flag, NZ to use Helmholtz-Kohlraush effect */ ); @@ -51,9 +52,10 @@ struct _cam02ref { /* Private: */ /* Scene parameters */ ViewingCondition Ev; /* Enumerated Viewing Condition */ + double Lv; /* Luminance of white in the Viewing/Image cd/m^2 */ + double La; /* Adapting/Surround Luminance cd/m^2 */ double Wxyz[3]; /* Reference/Adapted White XYZ (Y range 0.0 .. 1.0) */ double Yb; /* Relative Luminance of Background to reference white (Y range 0.0 .. 1.0) */ - double La; /* Adapting/Surround Luminance cd/m^2 */ double Yf; /* Flare as a fraction of the reference white (Y range 0.0 .. 1.0) */ double Fxyz[3]; /* The Flare white coordinates (typically the Ambient color) */ @@ -120,7 +122,7 @@ double Lv /* Luminence of white in the Viewing/Scene/Image field (cd/m^2) */ static void cam02ref_free(cam02ref *s); static int cam02ref_set_view(cam02ref *s, ViewingCondition Ev, double Wxyz[3], - double Yb, double La, double Lv, double Yf, double Fxyz[3], int hk); + double Yb, double La, double Lv, double Yf, double Yg, double Gxyz[3], int hk); static int cam02ref_XYZ_to_cam(cam02ref *s, double *Jab, double *xyz); static int cam02ref_cam_to_XYZ(cam02ref *s, double XYZ[3], double Jab[3]); @@ -156,7 +158,8 @@ double Yb, /* Relative Luminence of Background to reference white */ double Lv, /* Luminence of white in the Viewing/Scene/Image field (cd/m^2) */ /* Ignored if Ev is set to other than vc_none */ double Yf, /* Flare as a fraction of the reference white (Y range 0.0 .. 1.0) */ -double Fxyz[3], /* The Flare white coordinates (typically the Ambient color) */ +double Yg, /* Glare as a fraction of the ambient (Y range 0.0 .. 1.0) */ +double Gxyz[3], /* The Glare white coordinates (typically the Ambient color) */ int hk /* Flag, NZ to use Helmholtz-Kohlraush effect */ ) { double tt; @@ -171,9 +174,16 @@ int hk /* Flag, NZ to use Helmholtz-Kohlraush effect */ s->Yb = Yb > 0.005 ? Yb : 0.005; /* Set minimum to avoid divide by 0.0 */ s->La = La; s->Yf = Yf; - s->Fxyz[0] = Fxyz[0]; - s->Fxyz[1] = Fxyz[1]; - s->Fxyz[2] = Fxyz[2]; + if (Gxyz[0] > 0.0 && Gxyz[1] > 0.0 && Gxyz[2] > 0.0) { + tt = Wxyz[1]/Gxyz[1]; /* Scale to white ref white */ + s->Gxyz[0] = tt * Gxyz[0]; + s->Gxyz[1] = tt * Gxyz[1]; + s->Gxyz[2] = tt * Gxyz[2]; + } else { + s->Gxyz[0] = Wxyz[0]; + s->Gxyz[1] = Wxyz[1]; + s->Gxyz[2] = Wxyz[2]; + } s->hk = hk; /* Compute the internal parameters by category */ @@ -182,38 +192,42 @@ int hk /* Flag, NZ to use Helmholtz-Kohlraush effect */ s->C = 0.525; s->Nc = 0.8; s->F = 0.8; + Lv = La/0.033; break; case vc_dim: s->C = 0.59; s->Nc = 0.95; s->F = 0.9; + Lv = La/0.1; break; - case vc_cut_sheet: - s->C = 0.41; - s->Nc = 0.8; - s->F = 0.8; - break; + case vc_average: default: /* average */ s->C = 0.69; s->Nc = 1.0; s->F = 1.0; + Lv = La/0.2; + break; + case vc_cut_sheet: + s->C = 0.41; + s->Nc = 0.8; + s->F = 0.8; + Lv = La/0.02; // ??? break; } + s->Lv = Lv; /* Compute values that only change with viewing parameters */ /* Figure out the Flare contribution to the flareless XYZ input */ - tt = s->Yf * s->Wxyz[1]/s->Fxyz[1]; - s->Fsxyz[0] = tt * s->Fxyz[0]; - s->Fsxyz[1] = tt * s->Fxyz[1]; - s->Fsxyz[2] = tt * s->Fxyz[2]; - - /* Rescale so that the sum of the flare and the input doesn't exceed white */ - s->Fsc = s->Wxyz[1]/(s->Fsxyz[1] + s->Wxyz[1]); - s->Fsxyz[0] *= s->Fsc; - s->Fsxyz[1] *= s->Fsc; - s->Fsxyz[2] *= s->Fsc; - s->Fisc = 1.0/s->Fsc; + s->Fsxyz[0] = s->Yf * s->Wxyz[0]; + s->Fsxyz[1] = s->Yf * s->Wxyz[1]; + s->Fsxyz[2] = s->Yf * s->Wxyz[2]; + + /* Add in the Glare contribution from the ambient */ + tt = s->Yg * s->La/s->Lv; + s->Fsxyz[0] += tt * s->Gxyz[0]; + s->Fsxyz[1] += tt * s->Gxyz[1]; + s->Fsxyz[2] += tt * s->Gxyz[2]; /* Sharpened cone response white values */ s->rgbW[0] = 0.7328 * s->Wxyz[0] + 0.4296 * s->Wxyz[1] - 0.1624 * s->Wxyz[2]; |