--- /dev/null
+/*
+ * This file was part of gggl, it implements a variety of pixel conversion
+ * functions that are usable with babl, the file needs more cleanup, and
+ * doesn't return the number of samples processed as a long, like it's supposed to.
+ *
+ * GGGL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GGGL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GGGL; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Rights are granted to use this shared object in libraries covered by
+ * LGPL. (exception added, during import into babl CVS.)
+ *
+ * Copyright 2003, 2004, 2005 Øyvind Kolås <pippin@gimp.org>
+ */
+
+#include "babl.h"
+
+#define INLINE inline
+
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+/*
+ * Implemented according to information read from:
+ *
+ * http://www.cinenet.net/~spitzak/conversion/sketches_0265.pdf
+ *
+ * initially ignoring any diffusion, to keep the implementation
+ * smaller, and interchangeable with the non optimized version.
+ *
+ * due to ability to be able to relicence gggl under a different
+ * licence than GPL, I avoided the temptation to look at the
+ * source files in the same location, in case I was going to
+ * need this piece of code for projects where GPL compatibility
+ * was a must.
+ *
+ * TODO: error diffusion,
+ * gamma correction (not really,. gamma correction belongs in seperate ops,.
+ */
+
+
+/* lookup tables used in conversion */
+
+static float table_8_F[1 << 8];
+static float table_8g_F[1 << 8];
+static unsigned char table_F_8[1 << 16];
+static unsigned char table_F_8g[1 << 16];
+
+
+static int table_inited = 0;
+
+static void
+table_init (void)
+{
+ if (table_inited)
+ return;
+ table_inited = 1;
+
+ /* fill tables for conversion from integer to float */
+ {
+ int i;
+ for (i = 0; i < 1 << 8; i++)
+ {
+ float direct = i/255.0;
+ table_8_F[i] = direct;
+ table_8g_F[i] = pow(direct, 2.2F);
+ }
+ }
+ /* fill tables for conversion from float to integer */
+ {
+ union
+ {
+ float f;
+ unsigned short s[2];
+ } u;
+ u.f = 0.0;
+
+ u.s[0] = 0.0;
+
+ for (u.s[1] = 0; u.s[1] < 65535; u.s[1] += 1)
+ {
+ unsigned char c;
+ unsigned char cg;
+
+ if (u.f <= 0.0)
+ {
+ c = 0;
+ cg = 0;
+ }
+ else if (u.f >= 1.0)
+ {
+ c = 255;
+ cg = 255;
+ }
+ else
+ {
+ c = rint (u.f * 255.0);
+ cg = rint (pow(u.f,2.2F) * 255.0);
+ }
+
+ table_F_8[u.s[1]] = c;
+ table_F_8g[u.s[1]] = cg;
+ }
+ }
+ /* fix tables to ensure 1:1 conversions back and forth */
+ if (0)
+ {
+ int i;
+ for (i = 0; i < 256; i++)
+ {
+ float f = table_8_F[i];
+ unsigned short *hi = ((unsigned short *)(void*) &f);
+ unsigned short *lo = ((unsigned short *)(void*) &f);
+ *lo = 0;
+ table_F_8[(*hi)] = i;
+ }
+ }
+}
+
+/* function to find the index in table for a float */
+static unsigned int
+gggl_float_to_index16 (float f)
+{
+ union
+ {
+ float f;
+ unsigned short s[2];
+ } u;
+ u.f = f;
+ return u.s[1];
+}
+
+static INLINE long
+conv_F_8 (unsigned char *src, unsigned char *dst, long samples)
+{
+ if (!table_inited)
+ table_init ();
+ long n=samples;
+ while (n--)
+ {
+ register float f = (*(float *) src);
+ *(unsigned char *) dst = table_F_8[gggl_float_to_index16 (f)];
+ dst += 1;
+ src += 4;
+ }
+ return samples;
+}
+
+static INLINE long
+conv_8_F (unsigned char *src, unsigned char *dst, long samples)
+{
+ if (!table_inited)
+ table_init ();
+ long n=samples;
+ while (n--)
+ {
+ (*(float *) dst) = table_8_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+ }
+ return samples;
+}
+
+
+static INLINE long
+conv_rgbaF_rgb8 (unsigned char *src, unsigned char *dst, long samples)
+{
+ long n=samples;
+ while (n--)
+ {
+ register float f = (*(float *) src);
+ *(unsigned char *) dst = table_F_8[gggl_float_to_index16 (f)];
+ src += 4;
+ dst += 1;
+
+ f = (*(float *) src);
+ *(unsigned char *) dst = table_F_8[gggl_float_to_index16 (f)];
+ src += 4;
+ dst += 1;
+
+ f = (*(float *) src);
+ *(unsigned char *) dst = table_F_8[gggl_float_to_index16 (f)];
+ src += 4;
+ dst += 1;
+
+ src += 4;
+
+ }
+ return samples;
+}
+
+
+/*********/
+static INLINE long
+conv_rgbaF_rgba8 (unsigned char *src, unsigned char *dst, long samples)
+{
+ conv_F_8 (src, dst, samples * 4);
+ return samples;
+}
+
+#define conv_rgbaF_rgbP8 conv_rgbaF_rgba8
+
+static INLINE long
+conv_rgbF_rgb8 (unsigned char *src, unsigned char *dst, long samples)
+{
+ conv_F_8 (src, dst, samples * 3);
+ return samples;
+}
+
+static INLINE long
+conv_gaF_ga8 (unsigned char *src, unsigned char *dst, long samples)
+{
+ conv_F_8 (src, dst, samples * 2);
+ return samples;
+}
+
+#define conv_rgbAF_rgbA8 conv_rgbaF_rgba8
+#define conv_gF_g8 conv_F_8
+#define conv_gAF_gA8 conv_gaF_ga8
+
+
+static INLINE long
+conv_rgba8_rgbaF (unsigned char *src, unsigned char *dst, long samples)
+{
+ long n=samples;
+ while (n--)
+ {
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = table_8_F[*(unsigned char*) src];
+ dst += 4;
+ src += 1;
+ }
+ return samples;
+}
+
+static INLINE long
+conv_rgb8_rgbaF (unsigned char *src, unsigned char *dst, long samples)
+{
+ long n=samples;
+ while (n--)
+ {
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = table_8g_F[*(unsigned char *) src];
+ dst += 4;
+ src += 1;
+
+ (*(float *) dst) = 1.0;
+ dst += 4;
+ }
+ return samples;
+}
+
+static long
+conv_rgbAF_sdl32 (unsigned char *srcc,
+ unsigned char *dstc,
+ long samples)
+{
+ float *src = (void*)srcc;
+ unsigned char *dst = (void*)dstc;
+ long n=samples;
+ while (n--)
+ {
+ int i;
+ float alpha = src[3];
+ if (alpha < 0.0001)
+ alpha = 0.0001;
+ for (i=0;i<3;i++)
+ {
+ float ca=src[i];
+ float c;
+ int ret;
+ c=ca/alpha;
+ if (alpha==0.0)
+ ret=0;
+ else
+ ret = table_F_8g[gggl_float_to_index16 (c)];
+ if (ret<=0)
+ dst[i]=0;
+ else if (ret>255)
+ dst[i]=255;
+ else
+ dst[i] = ret;
+ }
+ {
+ int t=dst[0];
+ dst[0]=dst[2];
+ dst[2]=t;
+ dst[3]=255;
+ }
+ src += 4;
+ dst += 4;
+ }
+ return samples;
+}
+
+
+static long
+conv_rgbaF_sdl32 (unsigned char *srcc,
+ unsigned char *dstc,
+ long samples)
+{
+ float *src = (void*)srcc;
+ unsigned char *dst = (void*)dstc;
+ long n=samples;
+ while (n--)
+ {
+ dst[0] = table_F_8g[gggl_float_to_index16 (src[2])];
+ dst[1] = table_F_8g[gggl_float_to_index16 (src[1])];
+ dst[2] = table_F_8g[gggl_float_to_index16 (src[0])];
+ src += 4;
+ dst += 4;
+ }
+ return samples;
+}
+
+#define conv_rgb8_rgbAF conv_rgb8_rgbaF
+
+int
+init (void)
+{
+ Babl *rgbaF = babl_format_new (
+ babl_model ("RGBA"),
+ babl_type ("float"),
+ babl_component ("R"),
+ babl_component ("G"),
+ babl_component ("B"),
+ babl_component ("A"),
+ NULL);
+ Babl *rgbAF = babl_format_new (
+ babl_model ("RaGaBaA"),
+ babl_type ("float"),
+ babl_component ("Ra"),
+ babl_component ("Ga"),
+ babl_component ("Ba"),
+ babl_component ("A"),
+ NULL);
+ Babl *rgba8 = babl_format_new (
+ babl_model ("R'G'B'A"),
+ babl_type ("u8"),
+ babl_component ("R'"),
+ babl_component ("G'"),
+ babl_component ("B'"),
+ babl_component ("A"),
+ NULL);
+ Babl *rgb8 = babl_format_new (
+ babl_model ("R'G'B'"),
+ babl_type ("u8"),
+ babl_component ("R'"),
+ babl_component ("G'"),
+ babl_component ("B'"),
+ NULL);
+ Babl *sdl32 = babl_format_new (
+ babl_model ("R'G'B'"),
+ babl_type ("u8"),
+ babl_component ("B'"),
+ babl_component ("G'"),
+ babl_component ("R'"),
+ babl_component ("PAD"),
+ NULL);
+
+ table_init ();
+
+#define o(src,dst) \
+ babl_conversion_new (src, dst, "linear", conv_##src##_##dst, NULL)
+
+ o (rgb8, rgbaF);
+ o (rgb8, rgbAF);
+ o (rgba8, rgbaF);
+ o (rgbaF, sdl32);
+ o (rgbAF, sdl32);
+
+ return 0;
+}
projects / babl.git / commitdiff