BlinkenLib

@@ -214,6 +214,114 @@ static void copy_rect(stBlinkenMovie *pMovie, char *str_file,

   }

 }

+static stBlinkenMovie * scroll(stBlinkenMovie *pMovie,

+                               const char * str_direction,

+                               const char * str_width_height,

+                               const char * str_duration)

+{

+  enum {

+    DirNone, DirLeft, DirRight, DirUp, DirDown,

+  } dir = DirNone;

+  int width_height, duration, height, width, channels, maxval,

+      new_height, new_width, sy, sx, dy, dx, steps, step;

+  stBlinkenFrame *pScroll, *pFrame;

+

+  // direction

+  if (strcmp(str_direction, "left") == 0)

+    dir = DirLeft;

+  else if (strcmp(str_direction, "right") == 0)

+    dir = DirRight;

+  else if (strcmp(str_direction, "up") == 0)

+    dir = DirUp;

+  else if (strcmp(str_direction, "down") == 0)

+    dir = DirDown;

+

+  // check

+  if (dir == DirNone) {

+    printf("invalid direction \"%s\" for \"-S\" (left, right, up, down)\n",

+           str_direction);

+    return pMovie;

+  }

+  if (sscanf(str_width_height, "%u", &width_height) != 1 || width_height < 1) {

+    printf("invalid width/height \"%s\" for \"-S\"\n", str_width_height);

+    return pMovie;

+  }

+  if (sscanf(str_duration, "%u", &duration) != 1 || duration < 1) {

+    printf("invalid duration \"%s\" for \"-S\"\n", str_duration);

+    return pMovie;

+  }

+  if (BlinkenMovieGetFrameCnt(pMovie) < 1) {

+    printf("empty movie not allowed for \"-S\"\n");

+    return pMovie;

+  }

+

+  // get number of steps

+  height = BlinkenMovieGetHeight(pMovie);

+  width = BlinkenMovieGetWidth(pMovie);

+  channels = BlinkenMovieGetChannels(pMovie);

+  maxval = BlinkenMovieGetMaxval(pMovie);

+  new_height = height;

+  new_width = width;

+  sy = 0;

+  sx = 0;

+  dy = 1;

+  dx = 1;

+  switch (dir) {

+    case DirNone:

+      return pMovie;

+    case DirRight:

+      sx = 1; // prepare for sx *= steps

+      dx = -1;

+      // fall through

+    case DirLeft:

+      dy = 0;

+      steps = width - width_height + 1;

+      sx *= (steps - 1); // before this line, sx was 0 or 1

+      if (steps < 1) {

+        printf("invalid width %u for \"-S left/right\" on movie of width %u\n",

+               width_height, width);

+        return pMovie;

+      }

+      new_width = width_height;

+      break;

+    case DirDown:

+      sy = 1; // prepare for sy *= steps

+      dy = -1;

+      // fall through

+    case DirUp:

+      dx = 0;

+      steps = height - width_height + 1;

+      sy *= (steps - 1); // before this line, sy was 0 or 1

+      if (steps < 1) {

+        printf("invalid height %u for \"-S up/down\" on movie of height %u\n",

+               width_height, width);

+        return pMovie;

+      }

+      new_height = width_height;

+      break;

+  }

+

+  // get copy of first frame

+  pScroll = BlinkenFrameClone(BlinkenMovieGetFrame(pMovie, 1));

+  BlinkenFrameSetDuration(pScroll, duration);

+

+  // free old movie

+  BlinkenMovieFree(pMovie);

+

+  // create new movie scrolling the frame

+  pMovie = BlinkenMovieNew(new_height, new_width, channels, maxval);

+  for (step = 0; step < steps; ++step, sy += dy, sx += dx) {

+    pFrame = BlinkenFrameClone(pScroll);

+    BlinkenFrameCrop(pFrame, sy, sx, new_height, new_width);

+    BlinkenMovieAppendFrame(pMovie, pFrame);

+  }

+

+  // free scrolled frame

+  BlinkenFrameFree(pScroll);

+

+  return pMovie;

+}

+

 int main(int argCnt, char **args)

 {

   stBlinkenMovie *pMovie;

@@ -273,6 +381,8 @@ int main(int argCnt, char **args)

            "     generate a test movie and append it to current video\n"

            "  -C <file> <src-x>,<src-y> <width>x<height> <dest-x>,<dest-y>\n"

            "     copy rectangular section of other movie\n"

+           "  -S {left|right|up|down} <width/height> <duration>\n"

+           "     scroll first frame of current movie (duration in ms)\n"

            "  -Rcw\n"

            "     rotate movie 90 degrees clockwise\n"

            "  -Rccw\n"

@@ -639,6 +749,26 @@ int main(int argCnt, char **args)

       } else

         printf("missing file name of source movie for \"-C\"\n");

     }

+    // scroll first frame of current movie

+    else if (strcmp(args[i], "-S") == 0) {

+      if (i + 3 < argCnt) {

+        const char *str_direction, *str_width_height, *str_duration;

+        i++;

+        str_direction = args[i];

+        i++;

+        str_width_height = args[i];

+        i++;

+        str_duration = args[i];

+        pMovie = scroll(pMovie, str_direction, str_width_height, str_duration);

+      } else if (i + 2 < argCnt) {

+        printf("missing duration for \"-S\"\n");

+        i += 2;

+      } else if (i + 1 < argCnt) {

+        printf("missing width/height for \"-S\"\n");

+        i++;

+      } else

+        printf("missing direction (left, right, up, down) for \"-S\"\n");

+    }

     // rotate movie 90 degrees clockwise

     else if (strcmp(args[i], "-Rcw") == 0) {

       if (pMovie == NULL)