Initial revision

Originally committed as revision 5 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 214 insertions, 0 deletions

diff --git a/libavcodec/imgconvert.c b/libavcodec/imgconvert.c
new file mode 100644
index 0000000000..01289d4d83
--- /dev/null
+++ b/libavcodec/imgconvert.c
@@ -0,0 +1,214 @@
+/*
+ * Misc image convertion routines
+ * Copyright (c) 2001 Gerard Lantau.
+ *
+ * This program 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.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "avcodec.h"
+
+/* XXX: totally non optimized */
+
+static void yuv422_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr,
+                              UINT8 *src, int width, int height)
+{
+    int x, y;
+    UINT8 *p = src;
+
+    for(y=0;y<height;y+=2) {
+        for(x=0;x<width;x+=2) {
+            lum[0] = p[0];
+            cb[0] = p[1];
+            lum[1] = p[2];
+            cr[0] = p[3];
+            p += 4;
+            lum += 2;
+            cb++;
+            cr++;
+        }
+        for(x=0;x<width;x+=2) {
+            lum[0] = p[0];
+            lum[1] = p[2];
+            p += 4;
+            lum += 2;
+        }
+    }
+}
+
+#define SCALEBITS 8
+#define ONE_HALF  (1 << (SCALEBITS - 1))
+#define FIX(x)		((int) ((x) * (1L<<SCALEBITS) + 0.5))
+
+static void rgb24_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr,
+                              UINT8 *src, int width, int height)
+{
+    int wrap, wrap3, x, y;
+    int r, g, b, r1, g1, b1;
+    UINT8 *p;
+
+    wrap = width;
+    wrap3 = width * 3;
+    p = src;
+    for(y=0;y<height;y+=2) {
+        for(x=0;x<width;x+=2) {
+            r = p[0];
+            g = p[1];
+            b = p[2];
+            r1 = r;
+            g1 = g;
+            b1 = b;
+            lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            r = p[3];
+            g = p[4];
+            b = p[5];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            p += wrap3;
+            lum += wrap;
+
+            r = p[0];
+            g = p[1];
+            b = p[2];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            r = p[3];
+            g = p[4];
+            b = p[5];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            
+            cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 + 
+                      FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
+            cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 - 
+                     FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
+
+            cb++;
+            cr++;
+            p += -wrap3 + 2 * 3;
+            lum += -wrap + 2;
+        }
+        p += wrap3;
+        lum += wrap;
+    }
+}
+
+static void bgr24_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr,
+                              UINT8 *src, int width, int height)
+{
+    int wrap, wrap3, x, y;
+    int r, g, b, r1, g1, b1;
+    UINT8 *p;
+
+    wrap = width;
+    wrap3 = width * 3;
+    p = src;
+    for(y=0;y<height;y+=2) {
+        for(x=0;x<width;x+=2) {
+            b = p[0];
+            g = p[1];
+            r = p[2];
+            r1 = r;
+            g1 = g;
+            b1 = b;
+            lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            b = p[3];
+            g = p[4];
+            r = p[5];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            p += wrap3;
+            lum += wrap;
+
+            b = p[0];
+            g = p[1];
+            r = p[2];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            b = p[3];
+            g = p[4];
+            r = p[5];
+            r1 += r;
+            g1 += g;
+            b1 += b;
+            lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + 
+                      FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
+            
+            cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 + 
+                      FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
+            cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 - 
+                     FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
+
+            cb++;
+            cr++;
+            p += -wrap3 + 2 * 3;
+            lum += -wrap + 2;
+        }
+        p += wrap3;
+        lum += wrap;
+    }
+}
+
+int img_convert_to_yuv420(UINT8 *img_out, UINT8 *img, 
+                          int pix_fmt, int width, int height)
+{
+    UINT8 *pict;
+    int size, size_out;
+    UINT8 *picture[3];
+
+    pict = img_out;
+    size = width * height;
+    size_out = (size * 3) / 2;
+    picture[0] = pict;
+    picture[1] = pict + size;
+    picture[2] = picture[1] + (size / 4);
+
+    switch(pix_fmt) {
+    case PIX_FMT_YUV420P:
+        memcpy(pict, img, size_out);
+        break;
+    case PIX_FMT_YUV422:
+        yuv422_to_yuv420p(picture[0], picture[1], picture[2], 
+                          img, width, height);
+        break;
+    case PIX_FMT_RGB24:
+        rgb24_to_yuv420p(picture[0], picture[1], picture[2], 
+                         img, width, height);
+        break;
+    case PIX_FMT_BGR24:
+        bgr24_to_yuv420p(picture[0], picture[1], picture[2], 
+                         img, width, height);
+        break;
+    }
+    return size_out;
+}