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-rw-r--r--src/process/im_arithmetic_bin.cpp144
1 files changed, 143 insertions, 1 deletions
diff --git a/src/process/im_arithmetic_bin.cpp b/src/process/im_arithmetic_bin.cpp
index 494b6c0..575e650 100644
--- a/src/process/im_arithmetic_bin.cpp
+++ b/src/process/im_arithmetic_bin.cpp
@@ -2,7 +2,7 @@
* \brief Binary Arithmetic Operations
*
* See Copyright Notice in im_lib.h
- * $Id: im_arithmetic_bin.cpp,v 1.2 2009/10/01 02:56:58 scuri Exp $
+ * $Id: im_arithmetic_bin.cpp,v 1.3 2010/01/08 03:49:05 scuri Exp $
*/
@@ -262,6 +262,148 @@ void imProcessBlend(const imImage* src_image1, const imImage* src_image2, const
}
}
+#define COMPOSE_OVER(_SRC, _SRC_ALPHA, _DST, _TMP_MULTI, _TMP_ALPHA) (T)(((_SRC_ALPHA)*(_SRC) + (_TMP_MULTI)*(_DST)) / (_TMP_ALPHA))
+#define ALPHA_BLEND(_src,_dst,_alpha) (T)(((_src) * (_alpha) + (_dst) * (max - (_alpha))) / max)
+
+template <class T, class TA>
+static inline T compose_op(const T& v1, const T& v2, const T& alpha1, const T& alpha2, const TA& max)
+{
+ if (alpha1 != max) /* some transparency */
+ {
+ if (alpha1 != 0) /* source not full transparent */
+ {
+ if (alpha2 == 0) /* destiny full transparent */
+ {
+ return v1;
+ }
+ else if (alpha2 == max) /* destiny opaque */
+ {
+ return ALPHA_BLEND(v1, v2, alpha1);
+ }
+ else /* (0<alpha2<max && 0<alpha1<max) destiny and source are semi-transparent */
+ {
+ /* Closed Compositing SRC over DST (see smith95a.pdf) */
+ /* Colors NOT Premultiplied by Alpha */
+ /* DST = SRC * SRC_ALPHA + DST * DST_ALPHA * (1 - SRC_ALPHA) */
+ /* DST_ALPHA = SRC_ALPHA + DST_ALPHA * (1 - SRC_ALPHA) */
+ /* DST /= DST_ALPHA */
+ TA _tmp_multi = alpha2 * (max - alpha1);
+ TA _tmp_src_alpha = alpha1*max;
+ TA _tmp_alpha = _tmp_src_alpha + _tmp_multi;
+ return COMPOSE_OVER(v1, _tmp_src_alpha, v2, _tmp_multi, _tmp_alpha);
+ }
+ }
+ else /* (alpha1 == 0) source full transparent */
+ {
+ return v2;
+ }
+ }
+ else /* (alpha1 == max) source has no alpha = opaque */
+ {
+ return v1;
+ }
+}
+
+template <class T, class TA>
+static inline T compose_alpha_op(const T& alpha1, const T& alpha2, const TA& max)
+{
+ if (alpha1 != max) /* some transparency */
+ {
+ if (alpha1 != 0) /* source not full transparent */
+ {
+ if (alpha2 == 0) /* destiny full transparent */
+ {
+ return alpha1;
+ }
+ else if (alpha2 == max) /* destiny opaque */
+ {
+ /* alpha2 is not changed */
+ return alpha2;
+ }
+ else /* (0<alpha2<max && 0<alpha1<max) destiny and source are semi-transparent */
+ {
+ /* Closed Compositing SRC over DST (see smith95a.pdf) */
+ /* Colors NOT Premultiplied by Alpha */
+ /* DST = SRC * SRC_ALPHA + DST * DST_ALPHA * (1 - SRC_ALPHA) */
+ /* DST_ALPHA = SRC_ALPHA + DST_ALPHA * (1 - SRC_ALPHA) */
+ /* DST /= DST_ALPHA */
+ TA _tmp_multi = alpha2 * (max - alpha1);
+ TA _tmp_src_alpha = alpha1*max;
+ TA _tmp_alpha = _tmp_src_alpha + _tmp_multi;
+ return (T)(_tmp_alpha / max);
+ }
+ }
+ else /* (alpha1 == 0) source full transparent */
+ {
+ /* alpha2 is not changed */
+ return alpha2;
+ }
+ }
+ else /* (alpha1 == max) source has no alpha = opaque */
+ {
+ return (unsigned char)max; /* set destiny as opaque */
+ }
+}
+
+template <class T, class TA>
+static void DoCompose(T *map1, T *map2, T *alpha1, T *alpha2, T *map, int count, TA max)
+{
+ for (int i = 0; i < count; i++)
+ map[i] = compose_op(map1[i], map2[i], alpha1[i], alpha2[i], max);
+}
+
+template <class T, class TA>
+static void DoComposeAlpha(T *alpha1, T *alpha2, T *dst_alpha, int count, TA max)
+{
+ for (int i = 0; i < count; i++)
+ dst_alpha[i] = compose_alpha_op(alpha1[i], alpha2[i], max);
+}
+
+void imProcessCompose(const imImage* src_image1, const imImage* src_image2, imImage* dst_image)
+{
+ int count = src_image1->count,
+ src_alpha = src_image1->depth;
+
+ if (!src_image1->has_alpha || !src_image2->has_alpha || !dst_image->has_alpha)
+ return;
+
+ for (int i = 0; i < src_image1->depth; i++)
+ {
+ switch(src_image1->data_type)
+ {
+ case IM_BYTE:
+ DoCompose((imbyte*)src_image1->data[i], (imbyte*)src_image2->data[i], (imbyte*)src_image1->data[src_alpha], (imbyte*)src_image2->data[src_alpha], (imbyte*)dst_image->data[i], count, (int)255);
+ break;
+ case IM_USHORT:
+ DoCompose((imushort*)src_image1->data[i], (imushort*)src_image2->data[i], (imushort*)src_image1->data[src_alpha], (imushort*)src_image2->data[src_alpha], (imushort*)dst_image->data[i], count, (int)65535);
+ break;
+ case IM_INT:
+ DoCompose((int*)src_image1->data[i], (int*)src_image2->data[i], (int*)src_image1->data[src_alpha], (int*)src_image2->data[src_alpha], (int*)dst_image->data[i], count, (int)2147483647);
+ break;
+ case IM_FLOAT:
+ DoCompose((float*)src_image1->data[i], (float*)src_image2->data[i], (float*)src_image1->data[src_alpha], (float*)src_image2->data[src_alpha], (float*)dst_image->data[i], count, 1.0f);
+ break;
+ }
+ }
+
+ /* one more for the alpha channel */
+ switch(src_image1->data_type)
+ {
+ case IM_BYTE:
+ DoComposeAlpha((imbyte*)src_image1->data[src_alpha], (imbyte*)src_image2->data[src_alpha], (imbyte*)dst_image->data[src_alpha], count, (int)255);
+ break;
+ case IM_USHORT:
+ DoComposeAlpha((imushort*)src_image1->data[src_alpha], (imushort*)src_image2->data[src_alpha], (imushort*)dst_image->data[src_alpha], count, (int)65535);
+ break;
+ case IM_INT:
+ DoComposeAlpha((int*)src_image1->data[src_alpha], (int*)src_image2->data[src_alpha], (int*)dst_image->data[src_alpha], count, (int)2147483647);
+ break;
+ case IM_FLOAT:
+ DoComposeAlpha((float*)src_image1->data[src_alpha], (float*)src_image2->data[src_alpha], (float*)dst_image->data[src_alpha], count, 1.0f);
+ break;
+ }
+}
+
static void DoBinaryConstOpCpxReal(imcfloat *map1, float value, imcfloat *map, int count, int op)
{
int i;
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 01:27:14 +0000