Watermarking with exact colors.

Patch by Marcus Engene <hisfirstname(at)hislastname.se>

Originally committed as revision 5131 to svn://svn.ffmpeg.org/ffmpeg/trunk

vhook/watermark.c

@@ -2,6 +2,12 @@
  * Watermark Hook
  * Copyright (c) 2005 Marcus Engene myfirstname(at)mylastname.se
  *
+ * flags to watermark:
+ *  -m nbr = nbr is 0..1. 0 is the default mode, see below.
+ *  -t nbr = nbr is six digit hex. Threshold.
+ *  -f file = File is the filename of watermark image. You must specify this!
+ *
+ * MODE 0:
  * The watermarkpicture works like this. (Assuming colorintencities 0..0xff)
  * Per color do this:
  * If mask color is 0x80, no change to original frame.
@@ -10,14 +16,22 @@
  * If mask color is > 0x80 the abs difference is added to frame. If result
  * > 0xff, result = 0xff
  *
+ * You can override the 0x80 level with the -t flag. Eg if threshold is 000000
+ * the color values of watermark is added to destination.
+ *
  * This way a mask that is visible both in light pictures and in dark can be
  * made (fex by using a picture generated by gimp and the bump map tool).
  *
  * An example watermark file is at
  * http://engene.se/ffmpeg_watermark.gif
  *
+ * MODE 1:
+ * Per color do this:
+ * If mask color > threshold color, watermark pixel is going to be used.
+ *
  * Example usage:
- *  ffmpeg -i infile -vhook '/path/watermark.so -f wm.gif' out.mov
+ *  ffmpeg -i infile -vhook '/path/watermark.so -f wm.gif' -an out.mov
+ *  ffmpeg -i infile -vhook '/path/watermark.so -f wm.gif -m 1 -t 222222' -an out.mov
  *
  * Note that the entire vhook argument is encapsulated in ''. This
  * way, arguments to the vhook won't be mixed up with those to ffmpeg.
@@ -37,7 +51,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-//#include <stdlib.h>
+#include <stdlib.h>
 //#include <fcntl.h>
 #include <unistd.h>
 #include <stdarg.h>
@@ -69,6 +83,10 @@ typedef struct {
     AVStream       *st;
     int             is_done;
     AVFrame        *pFrameRGB;
+    int             thrR;
+    int             thrG;
+    int             thrB;
+    int             mode;
 } ContextInfo;
 
 int get_watermark_picture(ContextInfo *ci, int cleanup);
@@ -96,6 +114,7 @@ int Configure(void **ctxp, int argc, char *argv[])
 {
     ContextInfo *ci;
     int c;
+    int tmp = 0;
 
     if (0 == (*ctxp = av_mallocz(sizeof(ContextInfo)))) return -1;
     ci = (ContextInfo *) *ctxp;
@@ -103,13 +122,28 @@ int Configure(void **ctxp, int argc, char *argv[])
     optind = 1;
 
     // Struct is mallocz:ed so no need to reset.
+    ci->thrR = 0x80;
+    ci->thrG = 0x80;
+    ci->thrB = 0x80;
 
-    while ((c = getopt(argc, argv, "f:")) > 0) {
+    while ((c = getopt(argc, argv, "f:m:t:")) > 0) {
         switch (c) {
             case 'f':
                 strncpy(ci->filename, optarg, 1999);
                 ci->filename[1999] = 0;
                 break;
+            case 'm':
+                ci->mode = atoi(optarg);
+                break;
+            case 't':
+                if (1 != sscanf(optarg, "%x", &tmp)) {
+                    av_log(NULL, AV_LOG_ERROR, "Watermark: argument to -t must be a 6 digit hex number\n");
+                    return -1;
+                }
+                ci->thrR = (tmp >> 16) & 0xff;
+                ci->thrG = (tmp >> 8) & 0xff;
+                ci->thrB = (tmp >> 0) & 0xff;
+                break;
             default:
                 av_log(NULL, AV_LOG_ERROR, "Watermark: Unrecognized argument '%s'\n", argv[optind]);
                 return -1;
@@ -128,14 +162,14 @@ int Configure(void **ctxp, int argc, char *argv[])
 
 
 /****************************************************************************
- * Why is this a void returning functions? I want to be able to go wrong!
+ * For mode 0 (the original one)
  ****************************************************************************/
-void Process(void *ctx,
-             AVPicture *picture,
-             enum PixelFormat pix_fmt,
-             int src_width,
-             int src_height,
-             int64_t pts)
+void Process0(void *ctx,
+              AVPicture *picture,
+              enum PixelFormat pix_fmt,
+              int src_width,
+              int src_height,
+              int64_t pts)
 {
     ContextInfo *ci = (ContextInfo *) ctx;
     char *buf = 0;
@@ -146,7 +180,6 @@ void Process(void *ctx,
     int xm_size;
     int ym_size;
 
-//    int retval = -1;
     int x;
     int y;
     int offs, offsm;
@@ -156,9 +189,9 @@ void Process(void *ctx,
     uint32_t pixel;
     uint32_t pixelm;
     int tmp;
-
-
-//??    (void) ci;
+    int thrR = ci->thrR;
+    int thrG = ci->thrG;
+    int thrB = ci->thrB;
 
     if (pix_fmt != PIX_FMT_RGBA32) {
         int size;
@@ -201,17 +234,17 @@ void Process(void *ctx,
             pixel_meck = pixel & 0xff000000;
 
             // R
-            tmp = (int)((pixel >> 16) & 0xff) + (int)((pixelm >> 16) & 0xff) - 0x80;
+            tmp = (int)((pixel >> 16) & 0xff) + (int)((pixelm >> 16) & 0xff) - thrR;
             if (tmp > 255) tmp = 255;
             if (tmp < 0) tmp = 0;
             pixel_meck |= (tmp << 16) & 0xff0000;
             // G
-            tmp = (int)((pixel >> 8) & 0xff) + (int)((pixelm >> 8) & 0xff) - 0x80;
+            tmp = (int)((pixel >> 8) & 0xff) + (int)((pixelm >> 8) & 0xff) - thrG;
             if (tmp > 255) tmp = 255;
             if (tmp < 0) tmp = 0;
             pixel_meck |= (tmp << 8) & 0xff00;
             // B
-            tmp = (int)((pixel >> 0) & 0xff) + (int)((pixelm >> 0) & 0xff) - 0x80;
+            tmp = (int)((pixel >> 0) & 0xff) + (int)((pixelm >> 0) & 0xff) - thrB;
             if (tmp > 255) tmp = 255;
             if (tmp < 0) tmp = 0;
             pixel_meck |= (tmp << 0) & 0xff;
@@ -240,6 +273,112 @@ void Process(void *ctx,
 }
 
 
+/****************************************************************************
+ * For mode 1 (the original one)
+ ****************************************************************************/
+void Process1(void *ctx,
+              AVPicture *picture,
+              enum PixelFormat pix_fmt,
+              int src_width,
+              int src_height,
+              int64_t pts)
+{
+    ContextInfo *ci = (ContextInfo *) ctx;
+    char *buf = 0;
+    AVPicture picture1;
+    AVPicture *pict = picture;
+
+    AVFrame *pFrameRGB;
+    int xm_size;
+    int ym_size;
+
+    int x;
+    int y;
+    int offs, offsm;
+    int mpoffs;
+    uint32_t *p_pixel = 0;
+    uint32_t pixel;
+    uint32_t pixelm;
+
+    if (pix_fmt != PIX_FMT_RGBA32) {
+        int size;
+
+        size = avpicture_get_size(PIX_FMT_RGBA32, src_width, src_height);
+        buf = av_malloc(size);
+
+        avpicture_fill(&picture1, buf, PIX_FMT_RGBA32, src_width, src_height);
+        if (img_convert(&picture1, PIX_FMT_RGBA32,
+                        picture, pix_fmt, src_width, src_height) < 0) {
+            av_free(buf);
+            return;
+        }
+        pict = &picture1;
+    }
+
+    /* Insert filter code here */ /* ok */
+
+    // Get me next frame
+    if (0 > get_watermark_picture(ci, 0)) {
+        return;
+    }
+    // These are the three original static variables in the ffmpeg hack.
+    pFrameRGB = ci->pFrameRGB;
+    xm_size = ci->x_size;
+    ym_size = ci->y_size;
+
+    // I'll do the *4 => <<2 crap later. Most compilers understand that anyway.
+    // According to avcodec.h PIX_FMT_RGBA32 is handled in endian specific manner.
+    for (y=0; y<src_height; y++) {
+        offs = y * (src_width * 4);
+        offsm = (((y * ym_size) / src_height) * 4) * xm_size; // offsm first in maskline. byteoffs!
+        for (x=0; x<src_width; x++) {
+            mpoffs = offsm + (((x * xm_size) / src_width) * 4);
+            p_pixel = (uint32_t *)&((pFrameRGB->data[0])[mpoffs]);
+            pixelm = *p_pixel; /* watermark pixel */
+            p_pixel = (uint32_t *)&((pict->data[0])[offs]);
+            pixel = *p_pixel;
+
+            if (((pixelm >> 16) & 0xff) > ci->thrR ||
+                ((pixelm >>  8) & 0xff) > ci->thrG ||
+                ((pixelm >>  0) & 0xff) > ci->thrB)
+            {
+                *p_pixel = pixelm;
+            } else {
+                *p_pixel = pixel;
+            }
+            offs += 4;
+        } // foreach X
+    } // foreach Y
+
+    if (pix_fmt != PIX_FMT_RGBA32) {
+        if (img_convert(picture, pix_fmt,
+                        &picture1, PIX_FMT_RGBA32, src_width, src_height) < 0) {
+        }
+    }
+
+    av_free(buf);
+}
+
+
+/****************************************************************************
+ * This is the function ffmpeg.c callbacks.
+ ****************************************************************************/
+void Process(void *ctx,
+             AVPicture *picture,
+             enum PixelFormat pix_fmt,
+             int src_width,
+             int src_height,
+             int64_t pts)
+{
+    ContextInfo *ci = (ContextInfo *) ctx;
+    if (1 == ci->mode) {
+        return Process1(ctx, picture, pix_fmt, src_width, src_height, pts);
+    } else {
+        return Process0(ctx, picture, pix_fmt, src_width, src_height, pts);
+    }
+}
+
+
 /****************************************************************************
  * When cleanup == 0, we try to get the next frame. If no next frame, nothing
  * is done.