research.m1stereo.tv/gitweb/ - melted/blob - src/modules/motion_est/arrow_code.c

   1 /*
   2  *      /brief Draw arrows
   3  *      /author Zachary Drew, Copyright 2004
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software Foundation,
  17  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <framework/mlt_frame.h>
  21 #include "arrow_code.h"
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <math.h>
  26 #include <string.h>
  27
  28 #define MIN(a,b) ((a) > (b) ? (b) : (a))
  29
  30 #define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
  31 #define ABS(a) ((a) >= 0 ? (a) : (-(a)))
  32
  33
  34 static int w;
  35 static int h;
  36 static int xstride;
  37 static int ystride;
  38 static mlt_image_format format;
  39
  40 int init_arrows( mlt_image_format *image_format, int width, int height )
  41 {
  42         w = width;
  43         h = height;
  44         format = *image_format;
  45         switch( *image_format ) {
  46                 case mlt_image_yuv422:
  47                         xstride = 2;
  48                         ystride = xstride * w;
  49                         break;
  50                 default:
  51                         // I don't know
  52                         return 0;
  53         }
  54         return 1;
  55
  56 }
  57
  58 // ffmpeg borrowed
  59 static inline int clip(int a, int amin, int amax)
  60 {
  61     if (a < amin)
  62         return amin;
  63     else if (a > amax)
  64         return amax;
  65     else
  66         return a;
  67 }
  68
  69
  70 /**
  71  * draws an line from (ex, ey) -> (sx, sy).
  72  * Credits: modified from ffmpeg project
  73  * @param ystride stride/linesize of the image
  74  * @param xstride stride/element size of the image
  75  * @param color color of the arrow
  76  */
  77 void draw_line(uint8_t *buf, int sx, int sy, int ex, int ey, int color)
  78 {
  79     int t, x, y, fr, f;
  80
  81
  82     sx= clip(sx, 0, w-1);
  83     sy= clip(sy, 0, h-1);
  84     ex= clip(ex, 0, w-1);
  85     ey= clip(ey, 0, h-1);
  86
  87     buf[sy*ystride + sx*xstride]+= color;
  88
  89     if(ABS(ex - sx) > ABS(ey - sy)){
  90         if(sx > ex){
  91             t=sx; sx=ex; ex=t;
  92             t=sy; sy=ey; ey=t;
  93         }
  94         buf+= sx*xstride + sy*ystride;
  95         ex-= sx;
  96         f= ((ey-sy)<<16)/ex;
  97         for(x= 0; x <= ex; x++){
  98             y = (x*f)>>16;
  99             fr= (x*f)&0xFFFF;
 100             buf[ y   *ystride + x*xstride]+= (color*(0x10000-fr))>>16;
 101             buf[(y+1)*ystride + x*xstride]+= (color*         fr )>>16;
 102         }
 103     }else{
 104         if(sy > ey){
 105             t=sx; sx=ex; ex=t;
 106             t=sy; sy=ey; ey=t;
 107         }
 108         buf+= sx*xstride + sy*ystride;
 109         ey-= sy;
 110         if(ey) f= ((ex-sx)<<16)/ey;
 111         else   f= 0;
 112         for(y= 0; y <= ey; y++){
 113             x = (y*f)>>16;
 114             fr= (y*f)&0xFFFF;
 115             buf[y*ystride + x    *xstride]+= (color*(0x10000-fr))>>16;;
 116             buf[y*ystride + (x+1)*xstride]+= (color*         fr )>>16;;
 117         }
 118     }
 119 }
 120
 121 void draw_rectangle_fill(uint8_t *buf, int x, int y, int w, int h, int color)
 122 {
 123         int i,j;
 124         for ( i = 0; i < w; i++ )
 125                 for ( j = 0; j < h; j++ )
 126                         buf[ (y+j)*ystride + (x+i)*xstride] = color;
 127 }
 128
 129 void draw_rectangle_outline(uint8_t *buf, int x, int y, int w, int h, int color)
 130 {
 131         int i,j;
 132         for ( i = 0; i < w; i++ ) {
 133                 buf[ y*ystride + (x+i)*xstride ] += color;
 134                 buf[ (y+h)*ystride + (x+i)*xstride ] += color;
 135         }
 136         for ( j = 1; j < h+1; j++ ) {
 137                 buf[ (y+j)*ystride + x*xstride ] += color;
 138                 buf[ (y+j)*ystride + (x+w)*xstride ] += color;
 139         }
 140 }
 141 /**
 142  * draws an arrow from (ex, ey) -> (sx, sy).
 143  * Credits: modified from ffmpeg project
 144  * @param stride stride/linesize of the image
 145  * @param color color of the arrow
 146  */
 147 void draw_arrow(uint8_t *buf, int sx, int sy, int ex, int ey, int color){
 148
 149         int dx,dy;
 150         dx= ex - sx;
 151         dy= ey - sy;
 152
 153         if(dx*dx + dy*dy > 3*3){
 154                 int rx=  dx + dy;
 155                 int ry= -dx + dy;
 156                 int length= sqrt((rx*rx + ry*ry)<<8);
 157
 158                 rx= ROUNDED_DIV(rx*3<<4, length);
 159                 ry= ROUNDED_DIV(ry*3<<4, length);
 160
 161                 draw_line(buf, sx, sy, sx + rx, sy + ry, color);
 162                 draw_line(buf, sx, sy, sx - ry, sy + rx, color);
 163         }
 164         draw_line(buf, sx, sy, ex, ey, color);
 165 }