AuroraMiddleware/gtk
1
0
Fork 1
mirror of https://gitlab.gnome.org/GNOME/gtk.git synced 2025-01-01 00:11:29 +00:00
Code Issues Projects Releases Wiki Activity

gdk: Handle negative values in all transfer function

Browse Source 
Make sure that for all eotfs/oetfs, eotf(x) == -eotf(-x)

In particular, don't pass negative values to pow() and cause
undefined behavior.
This commit is contained in:
Matthias Clasen 2024-08-13 15:47:17 -04:00
parent 79c2df8392
commit e1fbd52c29
1 changed files with 23 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
gdk/gdkcolordefs.h
View File

@ -20,11 +20,17 @@
* and tests, and must not include other headers. * and tests, and must not include other headers.
*/ */
static inline int
sign (float v)
{
return v < 0 ? -1 : 1;
}
static inline float static inline float
srgb_oetf (float v) srgb_oetf (float v)
{ {
if (v > 0.0031308f) if (fabsf (v) > 0.0031308f)
return 1.055f * powf (v, 1.f / 2.4f) - 0.055f; return 1.055f * sign (v) * powf (fabsf (v), 1.f / 2.4f) - 0.055f;
else else
return 12.92f * v; return 12.92f * v;
} }
@ -32,8 +38,8 @@ srgb_oetf (float v)
static inline float static inline float
srgb_eotf (float v) srgb_eotf (float v)
{ {
if (v >= 0.04045f) if (fabsf (v) >= 0.04045f)
return powf (((v + 0.055f) / (1.f + 0.055f)), 2.4f); return sign (v) * powf (((fabsf (v) + 0.055f) / (1.f + 0.055f)), 2.4f);
else else
return v / 12.92f; return v / 12.92f;
} }
@ -41,25 +47,25 @@ srgb_eotf (float v)
static inline float static inline float
gamma22_oetf (float v) gamma22_oetf (float v)
{ {
return powf (v, 1.f / 2.2f); return sign (v) * powf (fabsf (v), 1.f / 2.2f);
} }
static inline float static inline float
gamma22_eotf (float v) gamma22_eotf (float v)
{ {
return powf (v, 2.2f); return sign (v) * powf (fabsf (v), 2.2f);
} }
static inline float static inline float
gamma28_oetf (float v) gamma28_oetf (float v)
{ {
return powf (v, 1.f / 2.8f); return sign (v) * powf (fabsf (v), 1.f / 2.8f);
} }
static inline float static inline float
gamma28_eotf (float v) gamma28_eotf (float v)
{ {
return powf (v, 2.8f); return sign (v) * powf (fabsf (v), 2.8f);
} }
static inline float static inline float
@ -71,9 +77,10 @@ pq_eotf (float v)
float c2 = 2413.0 / (1 << 7); float c2 = 2413.0 / (1 << 7);
float c3 = 2392.0 / (1 << 7); float c3 = 2392.0 / (1 << 7);
float x = powf (MAX ((powf (v, minv) - c1), 0) / (c2 - (c3 * (powf (v, minv)))), ninv); float x = powf (fabsf (v), minv);
x = powf (MAX ((x - c1), 0) / (c2 - (c3 * x)), ninv);
return x * 10000 / 203.0; return sign (v) * x * 10000 / 203.0;
} }
static inline float static inline float
@ -86,7 +93,8 @@ pq_oetf (float v)
float c2 = 2413.0 / (1 << 7); float c2 = 2413.0 / (1 << 7);
float c3 = 2392.0 / (1 << 7); float c3 = 2392.0 / (1 << 7);
return powf (((c1 + (c2 * powf (x, n))) / (1 + (c3 * powf (x, n)))), m); x = powf (fabsf (x), n);
return sign (v) * powf (((c1 + (c2 * x)) / (1 + (c3 * x))), m);
} }
static inline float static inline float
@ -95,10 +103,10 @@ bt709_eotf (float v)
const float a = 1.099; const float a = 1.099;
const float d = 0.0812; const float d = 0.0812;
if (v < d) if (fabsf (v) < d)
return v / 4.5f; return v / 4.5f;
else else
return powf ((v + (a - 1)) / a, 1 / 0.45f); return sign (v) * powf ((fabsf (v) + (a - 1)) / a, 1 / 0.45f);
} }
static inline float static inline float
@ -107,10 +115,10 @@ bt709_oetf (float v)
const float a = 1.099; const float a = 1.099;
const float b = 0.018; const float b = 0.018;
if (v < b) if (fabsf (v) < b)
return v * 4.5f; return v * 4.5f;
else else
return a * powf (v, 0.45f) - (a - 1); return a * sign (v) * powf (fabsf (v), 0.45f) - (a - 1);
} }
static inline float static inline float