[babl] babl: move trc functions inside babl-trc.c
- From: Øyvind Kolås <ok src gnome org>
- To: commits-list gnome org
- Cc:
- Subject: [babl] babl: move trc functions inside babl-trc.c
- Date: Thu, 31 Aug 2017 14:27:13 +0000 (UTC)
commit 52a48bfcd881602f1e84d39dd72b48fb93436e48
Author: Øyvind Kolås <pippin gimp org>
Date: Thu Aug 31 06:19:09 2017 +0200
babl: move trc functions inside babl-trc.c
Use lolremez 9 degree polynominal approximations for 1.8 and 2.2 gamma.
babl/babl-fish-path.c | 4 +-
babl/babl-trc.c | 486 +++++++++++++++++++++++++++++++++++++++++++++++++
babl/babl-trc.h | 372 -------------------------------------
3 files changed, 488 insertions(+), 374 deletions(-)
---
diff --git a/babl/babl-fish-path.c b/babl/babl-fish-path.c
index 4fe5ded..03e002f 100644
--- a/babl/babl-fish-path.c
+++ b/babl/babl-fish-path.c
@@ -431,7 +431,7 @@ static void prep_conversion (const Babl *babl)
lut = matrixf + 9;
for (i = 0; i < 256; i++)
{
- lut[i] = _babl_trc_to_linear (source_space->space.trc[0], i/255.0);
+ lut[i] = babl_trc_to_linear (source_space->space.trc[0], i/255.0);
// XXX: should have green and blue luts as well
}
}
@@ -698,7 +698,7 @@ babl_fish_path (const Babl *source,
if (!done)
{
- if(0)babl_conversion_class_for_each (show_item, (void*)source->format.space);
+ if(1)babl_conversion_class_for_each (show_item, (void*)source->format.space);
//babl_format_class_for_each (show_fmt, NULL);
//babl_model_class_for_each (show_fmt, NULL);
}
diff --git a/babl/babl-trc.c b/babl/babl-trc.c
index 3b32f74..6de0fd1 100644
--- a/babl/babl-trc.c
+++ b/babl/babl-trc.c
@@ -24,6 +24,492 @@
static BablTRC trc_db[MAX_TRCS];
+
+static inline float babl_trc_lut_from_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ int entry = value * trc->lut_size + 0.5;
+ float ret = trc->inv_lut[
+ (entry >= 0 && entry < trc->lut_size) ?
+ entry :
+ trc->lut_size-1];
+ /* XXX: fixme, do linear interpolation */
+ return ret;
+}
+
+static inline float babl_trc_lut_to_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ int entry = value * trc->lut_size + 0.5;
+ float ret = trc->lut[
+ (entry >= 0 && entry < trc->lut_size) ?
+ entry :
+ trc->lut_size-1];
+ /* XXX: fixme, do linear interpolation */
+ return ret;
+}
+
+static inline float _babl_trc_linear (const Babl *trc_, float value)
+{
+ return 1.0;
+}
+
+/* origin: FreeBSD /usr/src/lib/msun/src/e_powf.c, copied from musl */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian cygnus com.
+ */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+//#include "libm.h"
+
+/* Get a 32 bit int from a float. */
+#define GET_FLOAT_WORD(w,d) \
+do { \
+ union {float f; uint32_t i;} __u; \
+ __u.f = (d); \
+ (w) = __u.i; \
+} while (0)
+
+/* Set a float from a 32 bit int. */
+#define SET_FLOAT_WORD(d,w) \
+do { \
+ union {float f; uint32_t i;} __u; \
+ __u.i = (w); \
+ (d) = __u.f; \
+} while (0)
+
+
+static const float
+bp[] = {1.0, 1.5,},
+dp_h[] = { 0.0, 5.84960938e-01,}, /* 0x3f15c000 */
+dp_l[] = { 0.0, 1.56322085e-06,}, /* 0x35d1cfdc */
+two24 = 16777216.0, /* 0x4b800000 */
+huge = 1.0e30,
+tiny = 1.0e-30,
+/* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
+L1 = 6.0000002384e-01, /* 0x3f19999a */
+L2 = 4.2857143283e-01, /* 0x3edb6db7 */
+L3 = 3.3333334327e-01, /* 0x3eaaaaab */
+L4 = 2.7272811532e-01, /* 0x3e8ba305 */
+L5 = 2.3066075146e-01, /* 0x3e6c3255 */
+L6 = 2.0697501302e-01, /* 0x3e53f142 */
+P1 = 1.6666667163e-01, /* 0x3e2aaaab */
+P2 = -2.7777778450e-03, /* 0xbb360b61 */
+P3 = 6.6137559770e-05, /* 0x388ab355 */
+P4 = -1.6533901999e-06, /* 0xb5ddea0e */
+P5 = 4.1381369442e-08, /* 0x3331bb4c */
+lg2 = 6.9314718246e-01, /* 0x3f317218 */
+lg2_h = 6.93145752e-01, /* 0x3f317200 */
+lg2_l = 1.42860654e-06, /* 0x35bfbe8c */
+ovt = 4.2995665694e-08, /* -(128-log2(ovfl+.5ulp)) */
+cp = 9.6179670095e-01, /* 0x3f76384f =2/(3ln2) */
+cp_h = 9.6191406250e-01, /* 0x3f764000 =12b cp */
+cp_l = -1.1736857402e-04; /* 0xb8f623c6 =tail of cp_h */
+#if 0
+ivln2 = 1.4426950216e+00, /* 0x3fb8aa3b =1/ln2 */
+ivln2_h = 1.4426879883e+00, /* 0x3fb8aa00 =16b 1/ln2*/
+ivln2_l = 7.0526075433e-06; /* 0x36eca570 =1/ln2 tail*/
+#endif
+
+static inline float obabl_powf(float x, float y)
+{
+ float z,ax,z_h,z_l,p_h,p_l;
+ float y1,t1,t2,r,s,sn,t,u,v,w;
+ int32_t i,j,k,yisint,n;
+ int32_t hx,hy,ix,iy,is;
+
+ GET_FLOAT_WORD(hx, x);
+ GET_FLOAT_WORD(hy, y);
+ ix = hx & 0x7fffffff;
+ iy = hy & 0x7fffffff;
+
+#if 0
+ /* x**0 = 1, even if x is NaN */
+ if (iy == 0)
+ return 1.0f;
+#endif
+ /* 1**y = 1, even if y is NaN */
+ if (hx == 0x3f800000)
+ return 1.0f;
+ /* NaN if either arg is NaN */
+ if (ix > 0x7f800000 || iy > 0x7f800000)
+ return x + y;
+
+ /* determine if y is an odd int when x < 0
+ * yisint = 0 ... y is not an integer
+ * yisint = 1 ... y is an odd int
+ * yisint = 2 ... y is an even int
+ */
+ yisint = 0;
+ if (hx < 0) {
+ if (iy >= 0x4b800000)
+ yisint = 2; /* even integer y */
+ else if (iy >= 0x3f800000) {
+ k = (iy>>23) - 0x7f; /* exponent */
+ j = iy>>(23-k);
+ if ((j<<(23-k)) == iy)
+ yisint = 2 - (j & 1);
+ }
+ }
+#if 0
+ /* special value of y */
+ if (iy == 0x7f800000) { /* y is +-inf */
+ if (ix == 0x3f800000) /* (-1)**+-inf is 1 */
+ return 1.0f;
+ else if (ix > 0x3f800000) /* (|x|>1)**+-inf = inf,0 */
+ return hy >= 0 ? y : 0.0f;
+ else /* (|x|<1)**+-inf = 0,inf */
+ return hy >= 0 ? 0.0f: -y;
+ }
+ if (iy == 0x3f800000) /* y is +-1 */
+ return hy >= 0 ? x : 1.0f/x;
+ if (hy == 0x40000000) /* y is 2 */
+ return x*x;
+ if (hy == 0x3f000000) { /* y is 0.5 */
+ if (hx >= 0) /* x >= +0 */
+ return sqrtf(x);
+ }
+#endif
+
+ ax = fabsf(x);
+ /* special value of x */
+ if (ix == 0x7f800000 || ix == 0 || ix == 0x3f800000) { /* x is +-0,+-inf,+-1 */
+ z = ax;
+ if (hy < 0) /* z = (1/|x|) */
+ z = 1.0f/z;
+ if (hx < 0) {
+ if (((ix-0x3f800000)|yisint) == 0) {
+ z = (z-z)/(z-z); /* (-1)**non-int is NaN */
+ } else if (yisint == 1)
+ z = -z; /* (x<0)**odd = -(|x|**odd) */
+ }
+ return z;
+ }
+
+ sn = 1.0f; /* sign of result */
+ if (hx < 0) {
+ if (yisint == 0) /* (x<0)**(non-int) is NaN */
+ return (x-x)/(x-x);
+ if (yisint == 1) /* (x<0)**(odd int) */
+ sn = -1.0f;
+ }
+
+#if 0
+ /* |y| is huge */
+ if (iy > 0x4d000000) { /* if |y| > 2**27 */
+ /* over/underflow if x is not close to one */
+ if (ix < 0x3f7ffff8)
+ return hy < 0 ? sn*huge*huge : sn*tiny*tiny;
+ if (ix > 0x3f800007)
+ return hy > 0 ? sn*huge*huge : sn*tiny*tiny;
+ /* now |1-x| is tiny <= 2**-20, suffice to compute
+ log(x) by x-x^2/2+x^3/3-x^4/4 */
+ t = ax - 1; /* t has 20 trailing zeros */
+ w = (t*t)*(0.5f - t*(0.333333333333f - t*0.25f));
+ u = ivln2_h*t; /* ivln2_h has 16 sig. bits */
+ v = t*ivln2_l - w*ivln2;
+ t1 = u + v;
+ GET_FLOAT_WORD(is, t1);
+ SET_FLOAT_WORD(t1, is & 0xfffff000);
+ t2 = v - (t1-u);
+ } else
+#endif
+{
+ float s2,s_h,s_l,t_h,t_l;
+ n = 0;
+ /* take care subnormal number */
+ if (ix < 0x00800000) {
+ ax *= two24;
+ n -= 24;
+ GET_FLOAT_WORD(ix, ax);
+ }
+ n += ((ix)>>23) - 0x7f;
+ j = ix & 0x007fffff;
+ /* determine interval */
+ ix = j | 0x3f800000; /* normalize ix */
+ if (j <= 0x1cc471) /* |x|<sqrt(3/2) */
+ k = 0;
+ else if (j < 0x5db3d7) /* |x|<sqrt(3) */
+ k = 1;
+ else {
+ k = 0;
+ n += 1;
+ ix -= 0x00800000;
+ }
+ SET_FLOAT_WORD(ax, ix);
+
+ /* compute s = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
+ u = ax - bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
+ v = 1.0f/(ax+bp[k]);
+ s = u*v;
+ s_h = s;
+ GET_FLOAT_WORD(is, s_h);
+ SET_FLOAT_WORD(s_h, is & 0xfffff000);
+ /* t_h=ax+bp[k] High */
+ is = ((ix>>1) & 0xfffff000) | 0x20000000;
+ SET_FLOAT_WORD(t_h, is + 0x00400000 + (k<<21));
+ t_l = ax - (t_h - bp[k]);
+ s_l = v*((u - s_h*t_h) - s_h*t_l);
+ /* compute log(ax) */
+ s2 = s*s;
+ r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6)))));
+ r += s_l*(s_h+s);
+ s2 = s_h*s_h;
+ t_h = 3.0f + s2 + r;
+ GET_FLOAT_WORD(is, t_h);
+ SET_FLOAT_WORD(t_h, is & 0xfffff000);
+ t_l = r - ((t_h - 3.0f) - s2);
+ /* u+v = s*(1+...) */
+ u = s_h*t_h;
+ v = s_l*t_h + t_l*s;
+ /* 2/(3log2)*(s+...) */
+ p_h = u + v;
+ GET_FLOAT_WORD(is, p_h);
+ SET_FLOAT_WORD(p_h, is & 0xfffff000);
+ p_l = v - (p_h - u);
+ z_h = cp_h*p_h; /* cp_h+cp_l = 2/(3*log2) */
+ z_l = cp_l*p_h + p_l*cp+dp_l[k];
+ /* log2(ax) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
+ t = (float)n;
+ t1 = (((z_h + z_l) + dp_h[k]) + t);
+ GET_FLOAT_WORD(is, t1);
+ SET_FLOAT_WORD(t1, is & 0xfffff000);
+ t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
+ }
+
+ /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
+ GET_FLOAT_WORD(is, y);
+ SET_FLOAT_WORD(y1, is & 0xfffff000);
+ p_l = (y-y1)*t1 + y*t2;
+ p_h = y1*t1;
+ z = p_l + p_h;
+ GET_FLOAT_WORD(j, z);
+ if (j > 0x43000000) /* if z > 128 */
+ return sn*huge*huge; /* overflow */
+ else if (j == 0x43000000) { /* if z == 128 */
+ if (p_l + ovt > z - p_h)
+ return sn*huge*huge; /* overflow */
+ } else if ((j&0x7fffffff) > 0x43160000) /* z < -150 */ // FIXME: check should be (uint32_t)j >
0xc3160000
+ return sn*tiny*tiny; /* underflow */
+ else if (j == 0xc3160000) { /* z == -150 */
+ if (p_l <= z-p_h)
+ return sn*tiny*tiny; /* underflow */
+ }
+ /*
+ * compute 2**(p_h+p_l)
+ */
+ i = j & 0x7fffffff;
+ k = (i>>23) - 0x7f;
+ n = 0;
+ if (i > 0x3f000000) { /* if |z| > 0.5, set n = [z+0.5] */
+ n = j + (0x00800000>>(k+1));
+ k = ((n&0x7fffffff)>>23) - 0x7f; /* new k for n */
+ SET_FLOAT_WORD(t, n & ~(0x007fffff>>k));
+ n = ((n&0x007fffff)|0x00800000)>>(23-k);
+ if (j < 0)
+ n = -n;
+ p_h -= t;
+ }
+ t = p_l + p_h;
+ GET_FLOAT_WORD(is, t);
+ SET_FLOAT_WORD(t, is & 0xffff8000);
+ u = t*lg2_h;
+ v = (p_l-(t-p_h))*lg2 + t*lg2_l;
+ z = u + v;
+ w = v - (z - u);
+ t = z*z;
+ t1 = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
+ r = (z*t1)/(t1-2.0f) - (w+z*w);
+ z = 1.0f - (r - z);
+ GET_FLOAT_WORD(j, z);
+ j += n<<23;
+ if ((j>>23) <= 0) /* subnormal output */
+ z = scalbnf(z, n);
+ else
+ SET_FLOAT_WORD(z, j);
+ return sn*z;
+}
+
+static inline float babl_powf (float x, float y)
+{
+ return expf (y * logf (x));
+}
+
+static inline float _babl_trc_gamma_to_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ return babl_powf (value, trc->gamma);
+}
+
+static inline float _babl_trc_gamma_from_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ return babl_powf (value, trc->rgamma);
+}
+
+#define POLY_DEGREE 9
+
+static inline float _babl_trc_gamma_1_8_to_linear (const Babl *trc_, float x)
+{
+ if (x >= 0.01f && x <= 1.0f)
+ {
+#if POLY_DEGREE==9
+ float u = -2.9976517e+1f;
+ u = u * x + 1.2166704e+2f;
+ u = u * x + -2.0336221e+2f;
+ u = u * x + 1.8145976e+2f;
+ u = u * x + -9.4187362e+1f;
+ u = u * x + 2.9529147e+1f;
+ u = u * x + -6.013473f;
+ u = u * x + 1.8725695f;
+ u = u * x + 9.9435057e-3f;
+ return u * x + -3.0061697e-5f;
+#elif POLY_DEGREE==10
+ float u = 7.7739437e+1f;
+ u = u * x + -3.5356881e+2f;
+ u = u * x + 6.7648456e+2f;
+ u = u * x + -7.0946645e+2f;
+ u = u * x + 4.4648413e+2f;
+ u = u * x + -1.7452451e+2f;
+ u = u * x + 4.3126128e+1f;
+ u = u * x + -7.2036142f;
+ u = u * x + 1.9207626f;
+ u = u * x + 9.14659e-3f;
+ return u * x + -2.575215e-5f;
+#endif
+ }
+ return babl_powf (x, 1.8);
+}
+
+static inline float _babl_trc_gamma_1_8_from_linear (const Babl *trc_, float x)
+{
+ if (x >= 0.01f && x <= 1.0f)
+ {
+#if POLY_DEGREE==9
+ float u = 7.6987344e+2f;
+ u = u * x + -3.4624161e+3f;
+ u = u * x + 6.5169973e+3f;
+ u = u * x + -6.6683502e+3f;
+ u = u * x + 4.037826e+3f;
+ u = u * x + -1.4810227e+3f;
+ u = u * x + 3.2670293e+2f;
+ u = u * x + -4.3240358e+1f;
+ u = u * x + 4.6009555f;
+ return u * x + 3.6000385e-2f;
+#elif POLY_DEGREE==10
+ float u = -2.2269134e+3f;
+ u = u * x + 1.1122916e+4f;
+ u = u * x + -2.3689515e+4f;
+ u = u * x + 2.8091743e+4f;
+ u = u * x + -2.0332165e+4f;
+ u = u * x + 9.2757293e+3f;
+ u = u * x + -2.6697086e+3f;
+ u = u * x + 4.7661489e+2f;
+ u = u * x + -5.2577079e+1f;
+ u = u * x + 4.8359543f;
+ return u * x + 3.4288484e-2f;
+#endif
+ }
+ return babl_powf (x, 1.0f/1.8f);
+}
+
+static inline float _babl_trc_gamma_2_2_to_linear (const Babl *trc_, float x)
+{
+ if (x >= 0.01f && x <= 1.0f)
+ {
+#if POLY_DEGREE==9
+ float u = 1.4519824e+1f;
+ u = u * x + -5.6919938e+1f;
+ u = u * x + 9.1404232e+1f;
+ u = u * x + -7.7951568e+1f;
+ u = u * x + 3.8593448e+1f;
+ u = u * x + -1.1709313e+1f;
+ u = u * x + 2.594042f;
+ u = u * x + 4.716017e-1f;
+ u = u * x + -1.478392e-3f;
+ return u * x + 4.987805e-6f;
+#elif POLY_DEGREE==10
+ float u = -3.6278814e+1f;
+ u = u * x + 1.5984863e+2f;
+ u = u * x + -2.9493194e+2f;
+ u = u * x + 2.9678744e+2f;
+ u = u * x + -1.7840175e+2f;
+ u = u * x + 6.6563304e+1f;
+ u = u * x + -1.5968574e+1f;
+ u = u * x + 2.9224961f;
+ u = u * x + 4.5996165e-1f;
+ u = u * x + -1.306086e-3f;
+ return u * x + 4.1278131e-6f;
+#endif
+ }
+ return babl_powf (x, 2.2f);
+}
+
+static inline float _babl_trc_gamma_2_2_from_linear (const Babl *trc_, float x)
+{
+ if (x >= 0.01f && x <= 1.0f)
+ {
+#if POLY_DEGREE==9
+ float u = 1.0084733e+3f;
+ u = u * x + -4.5716932e+3f;
+ u = u * x + 8.6843755e+3f;
+ u = u * x + -8.9814293e+3f;
+ u = u * x + 5.5060078e+3f;
+ u = u * x + -2.0477969e+3f;
+ u = u * x + 4.5804658e+2f;
+ u = u * x + -6.0913328e+1f;
+ u = u * x + 5.8668695f;
+ return u * x + 7.1335777e-2f;
+#elif POLY_DEGREE==10
+ float u = -2.9423332e+3f;
+ u = u * x + 1.4803473e+4f;
+ u = u * x + -3.1791125e+4f;
+ u = u * x + 3.805972e+4f;
+ u = u * x + -2.7850114e+4f;
+ u = u * x + 1.2865342e+4f;
+ u = u * x + -3.7543241e+3f;
+ u = u * x + 6.7921578e+2f;
+ u = u * x + -7.5167916e+1f;
+ u = u * x + 6.239892f;
+ return u * x + 6.8539291e-2f;
+#endif
+ }
+ return babl_powf (x, 1.0/2.2);
+}
+
+
+static inline float _babl_trc_srgb_to_linear (const Babl *trc_, float value)
+{
+ return babl_gamma_2_2_to_linear (value);
+}
+
+static inline float _babl_trc_srgb_from_linear (const Babl *trc_, float value)
+{
+ return babl_linear_to_gamma_2_2f (value);
+}
+
+static inline float _babl_trc_from_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ return trc->fun_from_linear (trc_, value);
+}
+
+static inline float _babl_trc_to_linear (const Babl *trc_, float value)
+{
+ BablTRC *trc = (void*)trc_;
+ return trc->fun_to_linear (trc_, value);
+}
+
+
const Babl *
babl_trc (const char *name)
{
diff --git a/babl/babl-trc.h b/babl/babl-trc.h
index dbdf2fe..0c9c23a 100644
--- a/babl/babl-trc.h
+++ b/babl/babl-trc.h
@@ -47,378 +47,6 @@ typedef struct
float (*fun_from_linear)(const Babl *trc_, float val);
} BablTRC;
-
-static inline float babl_trc_lut_from_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- int entry = value * trc->lut_size + 0.5;
- float ret = trc->inv_lut[
- (entry >= 0 && entry < trc->lut_size) ?
- entry :
- trc->lut_size-1];
- /* XXX: fixme, do linear interpolation */
- return ret;
-}
-
-static inline float babl_trc_lut_to_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- int entry = value * trc->lut_size + 0.5;
- float ret = trc->lut[
- (entry >= 0 && entry < trc->lut_size) ?
- entry :
- trc->lut_size-1];
- /* XXX: fixme, do linear interpolation */
- return ret;
-}
-
-static inline float _babl_trc_linear (const Babl *trc_, float value)
-{
- return 1.0;
-}
-
-/* origin: FreeBSD /usr/src/lib/msun/src/e_powf.c, copied from musl */
-/*
- * Conversion to float by Ian Lance Taylor, Cygnus Support, ian cygnus com.
- */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-
-//#include "libm.h"
-
-/* Get a 32 bit int from a float. */
-#define GET_FLOAT_WORD(w,d) \
-do { \
- union {float f; uint32_t i;} __u; \
- __u.f = (d); \
- (w) = __u.i; \
-} while (0)
-
-/* Set a float from a 32 bit int. */
-#define SET_FLOAT_WORD(d,w) \
-do { \
- union {float f; uint32_t i;} __u; \
- __u.i = (w); \
- (d) = __u.f; \
-} while (0)
-
-
-static const float
-bp[] = {1.0, 1.5,},
-dp_h[] = { 0.0, 5.84960938e-01,}, /* 0x3f15c000 */
-dp_l[] = { 0.0, 1.56322085e-06,}, /* 0x35d1cfdc */
-two24 = 16777216.0, /* 0x4b800000 */
-huge = 1.0e30,
-tiny = 1.0e-30,
-/* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
-L1 = 6.0000002384e-01, /* 0x3f19999a */
-L2 = 4.2857143283e-01, /* 0x3edb6db7 */
-L3 = 3.3333334327e-01, /* 0x3eaaaaab */
-L4 = 2.7272811532e-01, /* 0x3e8ba305 */
-L5 = 2.3066075146e-01, /* 0x3e6c3255 */
-L6 = 2.0697501302e-01, /* 0x3e53f142 */
-P1 = 1.6666667163e-01, /* 0x3e2aaaab */
-P2 = -2.7777778450e-03, /* 0xbb360b61 */
-P3 = 6.6137559770e-05, /* 0x388ab355 */
-P4 = -1.6533901999e-06, /* 0xb5ddea0e */
-P5 = 4.1381369442e-08, /* 0x3331bb4c */
-lg2 = 6.9314718246e-01, /* 0x3f317218 */
-lg2_h = 6.93145752e-01, /* 0x3f317200 */
-lg2_l = 1.42860654e-06, /* 0x35bfbe8c */
-ovt = 4.2995665694e-08, /* -(128-log2(ovfl+.5ulp)) */
-cp = 9.6179670095e-01, /* 0x3f76384f =2/(3ln2) */
-cp_h = 9.6191406250e-01, /* 0x3f764000 =12b cp */
-cp_l = -1.1736857402e-04, /* 0xb8f623c6 =tail of cp_h */
-ivln2 = 1.4426950216e+00, /* 0x3fb8aa3b =1/ln2 */
-ivln2_h = 1.4426879883e+00, /* 0x3fb8aa00 =16b 1/ln2*/
-ivln2_l = 7.0526075433e-06; /* 0x36eca570 =1/ln2 tail*/
-
-static inline float obabl_powf(float x, float y)
-{
- float z,ax,z_h,z_l,p_h,p_l;
- float y1,t1,t2,r,s,sn,t,u,v,w;
- int32_t i,j,k,yisint,n;
- int32_t hx,hy,ix,iy,is;
-
- GET_FLOAT_WORD(hx, x);
- GET_FLOAT_WORD(hy, y);
- ix = hx & 0x7fffffff;
- iy = hy & 0x7fffffff;
-
-#if 0
- /* x**0 = 1, even if x is NaN */
- if (iy == 0)
- return 1.0f;
-#endif
- /* 1**y = 1, even if y is NaN */
- if (hx == 0x3f800000)
- return 1.0f;
- /* NaN if either arg is NaN */
- if (ix > 0x7f800000 || iy > 0x7f800000)
- return x + y;
-
- /* determine if y is an odd int when x < 0
- * yisint = 0 ... y is not an integer
- * yisint = 1 ... y is an odd int
- * yisint = 2 ... y is an even int
- */
- yisint = 0;
- if (hx < 0) {
- if (iy >= 0x4b800000)
- yisint = 2; /* even integer y */
- else if (iy >= 0x3f800000) {
- k = (iy>>23) - 0x7f; /* exponent */
- j = iy>>(23-k);
- if ((j<<(23-k)) == iy)
- yisint = 2 - (j & 1);
- }
- }
-#if 0
- /* special value of y */
- if (iy == 0x7f800000) { /* y is +-inf */
- if (ix == 0x3f800000) /* (-1)**+-inf is 1 */
- return 1.0f;
- else if (ix > 0x3f800000) /* (|x|>1)**+-inf = inf,0 */
- return hy >= 0 ? y : 0.0f;
- else /* (|x|<1)**+-inf = 0,inf */
- return hy >= 0 ? 0.0f: -y;
- }
- if (iy == 0x3f800000) /* y is +-1 */
- return hy >= 0 ? x : 1.0f/x;
- if (hy == 0x40000000) /* y is 2 */
- return x*x;
- if (hy == 0x3f000000) { /* y is 0.5 */
- if (hx >= 0) /* x >= +0 */
- return sqrtf(x);
- }
-#endif
-
- ax = fabsf(x);
- /* special value of x */
- if (ix == 0x7f800000 || ix == 0 || ix == 0x3f800000) { /* x is +-0,+-inf,+-1 */
- z = ax;
- if (hy < 0) /* z = (1/|x|) */
- z = 1.0f/z;
- if (hx < 0) {
- if (((ix-0x3f800000)|yisint) == 0) {
- z = (z-z)/(z-z); /* (-1)**non-int is NaN */
- } else if (yisint == 1)
- z = -z; /* (x<0)**odd = -(|x|**odd) */
- }
- return z;
- }
-
- sn = 1.0f; /* sign of result */
- if (hx < 0) {
- if (yisint == 0) /* (x<0)**(non-int) is NaN */
- return (x-x)/(x-x);
- if (yisint == 1) /* (x<0)**(odd int) */
- sn = -1.0f;
- }
-
-#if 0
- /* |y| is huge */
- if (iy > 0x4d000000) { /* if |y| > 2**27 */
- /* over/underflow if x is not close to one */
- if (ix < 0x3f7ffff8)
- return hy < 0 ? sn*huge*huge : sn*tiny*tiny;
- if (ix > 0x3f800007)
- return hy > 0 ? sn*huge*huge : sn*tiny*tiny;
- /* now |1-x| is tiny <= 2**-20, suffice to compute
- log(x) by x-x^2/2+x^3/3-x^4/4 */
- t = ax - 1; /* t has 20 trailing zeros */
- w = (t*t)*(0.5f - t*(0.333333333333f - t*0.25f));
- u = ivln2_h*t; /* ivln2_h has 16 sig. bits */
- v = t*ivln2_l - w*ivln2;
- t1 = u + v;
- GET_FLOAT_WORD(is, t1);
- SET_FLOAT_WORD(t1, is & 0xfffff000);
- t2 = v - (t1-u);
- } else
-#endif
-{
- float s2,s_h,s_l,t_h,t_l;
- n = 0;
- /* take care subnormal number */
- if (ix < 0x00800000) {
- ax *= two24;
- n -= 24;
- GET_FLOAT_WORD(ix, ax);
- }
- n += ((ix)>>23) - 0x7f;
- j = ix & 0x007fffff;
- /* determine interval */
- ix = j | 0x3f800000; /* normalize ix */
- if (j <= 0x1cc471) /* |x|<sqrt(3/2) */
- k = 0;
- else if (j < 0x5db3d7) /* |x|<sqrt(3) */
- k = 1;
- else {
- k = 0;
- n += 1;
- ix -= 0x00800000;
- }
- SET_FLOAT_WORD(ax, ix);
-
- /* compute s = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
- u = ax - bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
- v = 1.0f/(ax+bp[k]);
- s = u*v;
- s_h = s;
- GET_FLOAT_WORD(is, s_h);
- SET_FLOAT_WORD(s_h, is & 0xfffff000);
- /* t_h=ax+bp[k] High */
- is = ((ix>>1) & 0xfffff000) | 0x20000000;
- SET_FLOAT_WORD(t_h, is + 0x00400000 + (k<<21));
- t_l = ax - (t_h - bp[k]);
- s_l = v*((u - s_h*t_h) - s_h*t_l);
- /* compute log(ax) */
- s2 = s*s;
- r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6)))));
- r += s_l*(s_h+s);
- s2 = s_h*s_h;
- t_h = 3.0f + s2 + r;
- GET_FLOAT_WORD(is, t_h);
- SET_FLOAT_WORD(t_h, is & 0xfffff000);
- t_l = r - ((t_h - 3.0f) - s2);
- /* u+v = s*(1+...) */
- u = s_h*t_h;
- v = s_l*t_h + t_l*s;
- /* 2/(3log2)*(s+...) */
- p_h = u + v;
- GET_FLOAT_WORD(is, p_h);
- SET_FLOAT_WORD(p_h, is & 0xfffff000);
- p_l = v - (p_h - u);
- z_h = cp_h*p_h; /* cp_h+cp_l = 2/(3*log2) */
- z_l = cp_l*p_h + p_l*cp+dp_l[k];
- /* log2(ax) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
- t = (float)n;
- t1 = (((z_h + z_l) + dp_h[k]) + t);
- GET_FLOAT_WORD(is, t1);
- SET_FLOAT_WORD(t1, is & 0xfffff000);
- t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
- }
-
- /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
- GET_FLOAT_WORD(is, y);
- SET_FLOAT_WORD(y1, is & 0xfffff000);
- p_l = (y-y1)*t1 + y*t2;
- p_h = y1*t1;
- z = p_l + p_h;
- GET_FLOAT_WORD(j, z);
- if (j > 0x43000000) /* if z > 128 */
- return sn*huge*huge; /* overflow */
- else if (j == 0x43000000) { /* if z == 128 */
- if (p_l + ovt > z - p_h)
- return sn*huge*huge; /* overflow */
- } else if ((j&0x7fffffff) > 0x43160000) /* z < -150 */ // FIXME: check should be (uint32_t)j >
0xc3160000
- return sn*tiny*tiny; /* underflow */
- else if (j == 0xc3160000) { /* z == -150 */
- if (p_l <= z-p_h)
- return sn*tiny*tiny; /* underflow */
- }
- /*
- * compute 2**(p_h+p_l)
- */
- i = j & 0x7fffffff;
- k = (i>>23) - 0x7f;
- n = 0;
- if (i > 0x3f000000) { /* if |z| > 0.5, set n = [z+0.5] */
- n = j + (0x00800000>>(k+1));
- k = ((n&0x7fffffff)>>23) - 0x7f; /* new k for n */
- SET_FLOAT_WORD(t, n & ~(0x007fffff>>k));
- n = ((n&0x007fffff)|0x00800000)>>(23-k);
- if (j < 0)
- n = -n;
- p_h -= t;
- }
- t = p_l + p_h;
- GET_FLOAT_WORD(is, t);
- SET_FLOAT_WORD(t, is & 0xffff8000);
- u = t*lg2_h;
- v = (p_l-(t-p_h))*lg2 + t*lg2_l;
- z = u + v;
- w = v - (z - u);
- t = z*z;
- t1 = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
- r = (z*t1)/(t1-2.0f) - (w+z*w);
- z = 1.0f - (r - z);
- GET_FLOAT_WORD(j, z);
- j += n<<23;
- if ((j>>23) <= 0) /* subnormal output */
- z = scalbnf(z, n);
- else
- SET_FLOAT_WORD(z, j);
- return sn*z;
-}
-
-static inline float babl_powf (float x, float y)
-{
- return expf (y * logf (x));
-}
-
-static inline float _babl_trc_gamma_to_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- return babl_powf (value, trc->gamma);
-}
-
-static inline float _babl_trc_gamma_from_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- return babl_powf (value, trc->rgamma);
-}
-
-static inline float _babl_trc_gamma_2_2_to_linear (const Babl *trc_, float value)
-{
- return babl_powf (value, 2.2);
-}
-
-static inline float _babl_trc_gamma_2_2_from_linear (const Babl *trc_, float value)
-{
- return babl_powf (value, 1.0/2.2);
-}
-
-static inline float _babl_trc_gamma_1_8_to_linear (const Babl *trc_, float value)
-{
- return babl_powf (value, 1.8);
-}
-
-static inline float _babl_trc_gamma_1_8_from_linear (const Babl *trc_, float value)
-{
- return babl_powf (value, 1.0/1.8);
-}
-
-static inline float _babl_trc_srgb_to_linear (const Babl *trc_, float value)
-{
- return babl_gamma_2_2_to_linear (value);
-}
-
-static inline float _babl_trc_srgb_from_linear (const Babl *trc_, float value)
-{
- return babl_linear_to_gamma_2_2f (value);
-}
-
-static inline float _babl_trc_from_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- return trc->fun_from_linear (trc_, value);
-}
-
-static inline float _babl_trc_to_linear (const Babl *trc_, float value)
-{
- BablTRC *trc = (void*)trc_;
- return trc->fun_to_linear (trc_, value);
-}
-
void
babl_trc_class_init (void);
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