diff options
author | Brecht Van Lommel <brechtvanlommel@pandora.be> | 2012-01-08 17:55:53 +0400 |
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committer | Brecht Van Lommel <brechtvanlommel@pandora.be> | 2012-01-08 17:55:53 +0400 |
commit | 4487103e61ba1277027d8d4a9105a3f1b29e204c (patch) | |
tree | 7658f4570e1c0ded316ac94458e739f9ffeaa319 /source/blender/blenlib/intern/math_color_inline.c | |
parent | 3dead22c7322cf72ee63a003ba50940abc12e7c9 (diff) |
Color:
* Accelerated sRGB <=> linear conversion using lookup table, this can speed up
loading of images in the compositor and simple renders quite a bit.
* Dithering now uses the Floyd-Steinberg algorithm. Previously it would simply
randomize each pixel slightly, adding noise, now that should be reduced.
Patch #29309 by David M.
Diffstat (limited to 'source/blender/blenlib/intern/math_color_inline.c')
-rw-r--r-- | source/blender/blenlib/intern/math_color_inline.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/source/blender/blenlib/intern/math_color_inline.c b/source/blender/blenlib/intern/math_color_inline.c index aaaa065f14d..1247632cf79 100644 --- a/source/blender/blenlib/intern/math_color_inline.c +++ b/source/blender/blenlib/intern/math_color_inline.c @@ -105,5 +105,80 @@ MINLINE void linearrgb_to_srgb_predivide_v4(float srgb[4], const float linear[4] srgb[3] = linear[3]; } +/* LUT accelerated conversions */ + +extern float BLI_color_from_srgb_table[256]; +extern unsigned short BLI_color_to_srgb_table[0x10000]; + +MINLINE unsigned short to_srgb_table_lookup(const float f) +{ + union { + float f; + unsigned short us[2]; + } tmp; + tmp.f = f; +#ifdef __BIG_ENDIAN__ + return BLI_color_to_srgb_table[tmp.us[0]]; +#else + return BLI_color_to_srgb_table[tmp.us[1]]; +#endif +} + +MINLINE void linearrgb_to_srgb_ushort4(unsigned short srgb[4], const float linear[4]) +{ + srgb[0] = to_srgb_table_lookup(linear[0]); + srgb[1] = to_srgb_table_lookup(linear[1]); + srgb[2] = to_srgb_table_lookup(linear[2]); + srgb[3] = FTOUSHORT(linear[3]); +} + +MINLINE void linearrgb_to_srgb_ushort4_predivide(unsigned short srgb[4], const float linear[4]) +{ + float alpha, inv_alpha, t; + int i; + + if(linear[3] == 1.0f || linear[3] == 0.0f) { + linearrgb_to_srgb_ushort4(srgb, linear); + return; + } + + alpha = linear[3]; + inv_alpha = 1.0f/alpha; + + for(i=0; i<3; ++i) { + t = linear[i] * inv_alpha; + srgb[i] = (t < 1.0f)? to_srgb_table_lookup(t) * alpha : FTOUSHORT(linearrgb_to_srgb(t) * alpha); + } + + srgb[3] = FTOUSHORT(linear[3]); +} + +MINLINE void srgb_to_linearrgb_uchar4(float linear[4], const unsigned char srgb[4]) +{ + linear[0] = BLI_color_from_srgb_table[srgb[0]]; + linear[1] = BLI_color_from_srgb_table[srgb[1]]; + linear[2] = BLI_color_from_srgb_table[srgb[2]]; + linear[3] = srgb[3] * (1.0f/255.0f); +} + +MINLINE void srgb_to_linearrgb_uchar4_predivide(float linear[4], const unsigned char srgb[4]) +{ + float alpha, inv_alpha; + int i; + + if(srgb[3] == 255 || srgb[3] == 0) { + srgb_to_linearrgb_uchar4(linear, srgb); + return; + } + + alpha = srgb[3] * (1.0f/255.0f); + inv_alpha = 1.0f/alpha; + + for(i=0; i<3; ++i) + linear[i] = linearrgb_to_srgb(srgb[i] * inv_alpha) * alpha; + + linear[3] = alpha; +} + #endif /* BLI_MATH_COLOR_INLINE_H */ |