gstreamer/gst/videomixer/blend_bgra.c

133 lines
3.8 KiB
C

/*
* Copyright (C) 2009 Alex Ugarte <augarte@vicomtech.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <gst/gst.h>
#define BLEND_NORMAL(B1,G1,R1,B2,G2,R2,B,G,R,alpha) \
B = ((B1*(255-alpha))+(B2*alpha))>>8; \
G = ((G1*(255-alpha))+(G2*alpha))>>8; \
R = ((R1*(255-alpha))+(R2*alpha))>>8;
#define BLEND_MODE BLEND_NORMAL
#define CREATE_FUNCTIONS(name, a, r, g, b) \
void \
gst_videomixer_blend_##name##_##name (guint8 * src, gint xpos, gint ypos, \
gint src_width, gint src_height, gdouble src_alpha, \
guint8 * dest, gint dest_width, gint dest_height) \
{ \
gint alpha, b_alpha; \
gint i, j; \
gint src_stride, dest_stride; \
gint src_add, dest_add; \
gint B, G, R; \
\
src_stride = src_width * 4; \
dest_stride = dest_width * 4; \
\
b_alpha = (gint) (src_alpha * 255); \
\
/* adjust src pointers for negative sizes */ \
if (xpos < 0) { \
src += -xpos * 4; \
src_width -= -xpos; \
xpos = 0; \
} \
if (ypos < 0) { \
src += -ypos * src_stride; \
src_height -= -ypos; \
ypos = 0; \
} \
/* adjust width/height if the src is bigger than dest */ \
if (xpos + src_width > dest_width) { \
src_width = dest_width - xpos; \
} \
if (ypos + src_height > dest_height) { \
src_height = dest_height - ypos; \
} \
\
src_add = src_stride - (4 * src_width); \
dest_add = dest_stride - (4 * src_width); \
\
dest = dest + 4 * xpos + (ypos * dest_stride); \
\
for (i = 0; i < src_height; i++) { \
for (j = 0; j < src_width; j++) { \
alpha = (src[a] * b_alpha) >> 8; \
BLEND_MODE (dest[b], dest[g], dest[r], src[b], src[g], src[r], \
B, G, R, alpha); \
dest[b] = B; \
dest[g] = G; \
dest[r] = R; \
dest[a] = 0xff; \
\
src += 4; \
dest += 4; \
} \
src += src_add; \
dest += dest_add; \
} \
} \
\
/* fill a buffer with a checkerboard pattern */ \
void \
gst_videomixer_fill_##name##_checker (guint8 * dest, gint width, gint height) \
{ \
gint i, j; \
static const int tab[] = { 80, 160, 80, 160 }; \
\
for (i = 0; i < height; i++) { \
for (j = 0; j < width; j++) { \
dest[b] = tab[((i & 0x8) >> 3) + ((j & 0x8) >> 3)]; /* blue */ \
dest[g] = tab[((i & 0x8) >> 3) + ((j & 0x8) >> 3)]; /* green */ \
dest[r] = tab[((i & 0x8) >> 3) + ((j & 0x8) >> 3)]; /* red */ \
dest[a] = 0xFF; /* alpha */ \
dest += 4; \
} \
} \
} \
\
void \
gst_videomixer_fill_##name##_color (guint8 * dest, gint width, gint height, \
gint colY, gint colU, gint colV) \
{ \
gint red, green, blue; \
gint i, j; \
\
red = CLAMP (1.164 * (colY - 16) + 1.596 * (colV - 128), 0, 255); \
green = \
CLAMP (1.164 * (colY - 16) - 0.813 * (colV - 128) - 0.391 * (colU - 128), \
0, 255); \
blue = CLAMP (1.164 * (colY - 16) + 2.018 * (colU - 128), 0, 255); \
\
for (i = 0; i < height; i++) { \
for (j = 0; j < width; j++) { \
dest[b] = blue; \
dest[g] = green; \
dest[r] = red; \
dest[a] = 0xff; \
dest += 4; \
} \
} \
}
CREATE_FUNCTIONS (argb, 0, 1, 2, 3);
CREATE_FUNCTIONS (bgra, 3, 2, 1, 0);
#undef BLEND_MODE