modules/video_filter/motiondetect.c

   1 /*****************************************************************************
   2  * motiondetect.c : Second version of a motion detection plugin.
   3  *****************************************************************************
   4  * Copyright (C) 2000-2008 VLC authors and VideoLAN
   5  *
   6  * Authors: Antoine Cellerier <dionoea -at- videolan -dot- org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 /*****************************************************************************
  24  * Preamble
  25  *****************************************************************************/
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_sout.h>
  34 #include <vlc_filter.h>
  35 #include <vlc_picture.h>
  36 #include "filter_picture.h"
  37
  38 /*****************************************************************************
  39  * Module descriptor
  40  *****************************************************************************/
  41 static int  Create    ( vlc_object_t * );
  42 static void Destroy   ( vlc_object_t * );
  43
  44 #define FILTER_PREFIX "motiondetect-"
  45
  46 vlc_module_begin ()
  47     set_description( N_("Motion detect video filter") )
  48     set_shortname( N_( "Motion Detect" ))
  49     set_category( CAT_VIDEO )
  50     set_subcategory( SUBCAT_VIDEO_VFILTER )
  51     set_capability( "video filter", 0 )
  52
  53     add_shortcut( "motion" )
  54     set_callbacks( Create, Destroy )
  55 vlc_module_end ()
  56
  57
  58 /*****************************************************************************
  59  * Local prototypes
  60  *****************************************************************************/
  61 static picture_t *Filter( filter_t *, picture_t * );
  62 static void GaussianConvolution( uint32_t *, uint32_t *, int, int, int );
  63 static int FindShapes( uint32_t *, uint32_t *, int, int, int,
  64                        int *, int *, int *, int *, int *);
  65 static void Draw( filter_t *p_filter, uint8_t *p_pix, int i_pix_pitch, int i_pix_size );
  66 #define NUM_COLORS (5000)
  67
  68 typedef struct
  69 {
  70     bool is_yuv_planar;
  71     picture_t *p_old;
  72     uint32_t *p_buf;
  73     uint32_t *p_buf2;
  74
  75     /* */
  76     int i_colors;
  77     int colors[NUM_COLORS];
  78     int color_x_min[NUM_COLORS];
  79     int color_x_max[NUM_COLORS];
  80     int color_y_min[NUM_COLORS];
  81     int color_y_max[NUM_COLORS];
  82 } filter_sys_t;
  83
  84 /*****************************************************************************
  85  * Create
  86  *****************************************************************************/
  87 static int Create( vlc_object_t *p_this )
  88 {
  89     filter_t *p_filter = (filter_t *)p_this;
  90     const video_format_t *p_fmt = &p_filter->fmt_in.video;
  91     filter_sys_t *p_sys;
  92     bool is_yuv_planar;
  93
  94     switch( p_fmt->i_chroma )
  95     {
  96         CASE_PLANAR_YUV
  97             is_yuv_planar = true;
  98             break;
  99
 100         CASE_PACKED_YUV_422
 101             is_yuv_planar = false;
 102             break;
 103
 104         default:
 105             msg_Err( p_filter, "Unsupported input chroma (%4.4s)",
 106                      (char*)&(p_fmt->i_chroma) );
 107             return VLC_EGENERIC;
 108     }
 109     p_filter->pf_video_filter = Filter;
 110
 111     /* Allocate structure */
 112     p_filter->p_sys = p_sys = malloc( sizeof( filter_sys_t ) );
 113     if( p_filter->p_sys == NULL )
 114         return VLC_ENOMEM;
 115
 116     p_sys->is_yuv_planar = is_yuv_planar;
 117     p_sys->p_old = NULL;
 118     p_sys->p_buf  = calloc( p_fmt->i_width * p_fmt->i_height, sizeof(*p_sys->p_buf) );
 119     p_sys->p_buf2 = calloc( p_fmt->i_width * p_fmt->i_height, sizeof(*p_sys->p_buf) );
 120
 121     if( !p_sys->p_buf || !p_sys->p_buf2 )
 122     {
 123         free( p_sys->p_buf2 );
 124         free( p_sys->p_buf );
 125         return VLC_ENOMEM;
 126     }
 127
 128     return VLC_SUCCESS;
 129 }
 130
 131 /*****************************************************************************
 132  * Destroy
 133  *****************************************************************************/
 134 static void Destroy( vlc_object_t *p_this )
 135 {
 136     filter_t *p_filter = (filter_t *)p_this;
 137     filter_sys_t *p_sys = p_filter->p_sys;
 138
 139     free( p_sys->p_buf2 );
 140     free( p_sys->p_buf );
 141     if( p_sys->p_old )
 142         picture_Release( p_sys->p_old );
 143     free( p_sys );
 144 }
 145
 146
 147 /*****************************************************************************
 148  * Filter YUV Planar/Packed
 149  *****************************************************************************/
 150 static void PreparePlanar( filter_t *p_filter, picture_t *p_inpic )
 151 {
 152     filter_sys_t *p_sys = p_filter->p_sys;
 153     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 154
 155     uint8_t *p_oldpix   = p_sys->p_old->p[Y_PLANE].p_pixels;
 156     const int i_old_pitch = p_sys->p_old->p[Y_PLANE].i_pitch;
 157
 158     const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
 159     const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
 160
 161     /**
 162      * Substract Y planes
 163      */
 164     for( unsigned y = 0; y < p_fmt->i_height; y++ )
 165     {
 166         for( unsigned x = 0; x < p_fmt->i_width; x++ )
 167             p_sys->p_buf2[y*p_fmt->i_width+x] = abs( p_inpix[y*i_src_pitch+x] - p_oldpix[y*i_old_pitch+x] );
 168     }
 169
 170     int i_chroma_dx;
 171     int i_chroma_dy;
 172     switch( p_inpic->format.i_chroma )
 173     {
 174         case VLC_CODEC_I420:
 175         case VLC_CODEC_J420:
 176         case VLC_CODEC_YV12:
 177             i_chroma_dx = 2;
 178             i_chroma_dy = 2;
 179             break;
 180
 181         case VLC_CODEC_I422:
 182         case VLC_CODEC_J422:
 183             i_chroma_dx = 2;
 184             i_chroma_dy = 1;
 185             break;
 186
 187         default:
 188             msg_Warn( p_filter, "Not taking chroma into account" );
 189             return;
 190     }
 191
 192     const uint8_t *p_inpix_u = p_inpic->p[U_PLANE].p_pixels;
 193     const uint8_t *p_inpix_v = p_inpic->p[V_PLANE].p_pixels;
 194     const int i_src_pitch_u = p_inpic->p[U_PLANE].i_pitch;
 195     const int i_src_pitch_v = p_inpic->p[V_PLANE].i_pitch;
 196
 197     const uint8_t *p_oldpix_u = p_sys->p_old->p[U_PLANE].p_pixels;
 198     const uint8_t *p_oldpix_v = p_sys->p_old->p[V_PLANE].p_pixels;
 199     const int i_old_pitch_u = p_sys->p_old->p[U_PLANE].i_pitch;
 200     const int i_old_pitch_v = p_sys->p_old->p[V_PLANE].i_pitch;
 201
 202     for( unsigned y = 0; y < p_fmt->i_height/i_chroma_dy; y++ )
 203     {
 204         for( unsigned x = 0; x < p_fmt->i_width/i_chroma_dx; x ++ )
 205         {
 206             const int d = abs( p_inpix_u[y*i_src_pitch_u+x] - p_oldpix_u[y*i_old_pitch_u+x] ) +
 207                           abs( p_inpix_v[y*i_src_pitch_v+x] - p_oldpix_v[y*i_old_pitch_v+x] );
 208
 209             for( int j = 0; j < i_chroma_dy; j++ )
 210             {
 211                 for( int i = 0; i < i_chroma_dx; i++ )
 212                     p_sys->p_buf2[i_chroma_dy*p_fmt->i_width*j + i_chroma_dx*i] = d;
 213             }
 214         }
 215     }
 216 }
 217
 218 static int PreparePacked( filter_t *p_filter, picture_t *p_inpic, int *pi_pix_offset )
 219 {
 220     filter_sys_t *p_sys = p_filter->p_sys;
 221     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 222
 223     int i_y_offset, i_u_offset, i_v_offset;
 224     if( GetPackedYuvOffsets( p_fmt->i_chroma,
 225                              &i_y_offset, &i_u_offset, &i_v_offset ) )
 226     {
 227         msg_Warn( p_filter, "Unsupported input chroma (%4.4s)",
 228                   (char*)&p_fmt->i_chroma );
 229         return VLC_EGENERIC;
 230     }
 231     *pi_pix_offset = i_y_offset;
 232
 233     /* Substract all planes at once */
 234     uint8_t *p_oldpix   = p_sys->p_old->p[Y_PLANE].p_pixels;
 235     const int i_old_pitch = p_sys->p_old->p[Y_PLANE].i_pitch;
 236
 237     const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
 238     const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
 239
 240     for( unsigned y = 0; y < p_fmt->i_height; y++ )
 241     {
 242         for( unsigned x = 0; x < p_fmt->i_width; x+=2 )
 243         {
 244             int d;
 245             d = abs( p_inpix[y*i_src_pitch+2*x+i_u_offset] - p_oldpix[y*i_old_pitch+2*x+i_u_offset] ) +
 246                 abs( p_inpix[y*i_src_pitch+2*x+i_v_offset] - p_oldpix[y*i_old_pitch+2*x+i_v_offset] );
 247
 248             for( int i = 0; i < 2; i++ )
 249                 p_sys->p_buf2[y*p_fmt->i_width+x+i] =
 250                     abs( p_inpix[y*i_src_pitch+2*(x+i)+i_y_offset] - p_oldpix[y*i_old_pitch+2*(x+i)+i_y_offset] ) + d;
 251         }
 252     }
 253     return VLC_SUCCESS;
 254 }
 255
 256 static picture_t *Filter( filter_t *p_filter, picture_t *p_inpic )
 257 {
 258     filter_sys_t *p_sys = p_filter->p_sys;
 259
 260     if( !p_inpic )
 261         return NULL;
 262
 263     picture_t *p_outpic = filter_NewPicture( p_filter );
 264     if( !p_outpic )
 265     {
 266         picture_Release( p_inpic );
 267         return NULL;
 268     }
 269     picture_Copy( p_outpic, p_inpic );
 270
 271     if( !p_sys->p_old )
 272     {
 273         p_sys->p_old = picture_Hold( p_inpic );
 274         goto exit;
 275     }
 276
 277     int i_pix_offset;
 278     int i_pix_size;
 279     if( p_sys->is_yuv_planar )
 280     {
 281         PreparePlanar( p_filter, p_inpic );
 282         i_pix_offset = 0;
 283         i_pix_size = 1;
 284     }
 285     else
 286     {
 287         if( PreparePacked( p_filter, p_inpic, &i_pix_offset ) )
 288             goto exit;
 289         i_pix_size = 2;
 290     }
 291
 292     /**
 293      * Get the areas where movement was detected
 294      */
 295     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 296     p_sys->i_colors = FindShapes( p_sys->p_buf2, p_sys->p_buf, p_fmt->i_width, p_fmt->i_width, p_fmt->i_height,
 297                                   p_sys->colors, p_sys->color_x_min, p_sys->color_x_max, p_sys->color_y_min, p_sys->color_y_max );
 298
 299     /**
 300      * Count final number of shapes
 301      * Draw rectangles (there can be more than 1 moving shape in 1 rectangle)
 302      */
 303     Draw( p_filter, &p_outpic->p[Y_PLANE].p_pixels[i_pix_offset], p_outpic->p[Y_PLANE].i_pitch, i_pix_size );
 304
 305     /* We're done. Lets keep a copy of the picture */
 306     picture_Release( p_sys->p_old );
 307     p_sys->p_old = picture_Hold( p_inpic );
 308
 309 exit:
 310     picture_Release( p_inpic );
 311     return p_outpic;
 312 }
 313
 314
 315 /*****************************************************************************
 316  * Gaussian Convolution
 317  *****************************************************************************
 318  *    Gaussian convolution ( sigma == 1.4 )
 319  *
 320  *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 321  *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 322  *    |  5 12 15 12  5  | ~ |  4 12 16 12  4 |
 323  *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 324  *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 325  *****************************************************************************/
 326 static void GaussianConvolution( uint32_t *p_inpix, uint32_t *p_smooth,
 327                                  int i_src_pitch, int i_num_lines,
 328                                  int i_src_visible )
 329 {
 330     /* A bit overkill but ... simpler */
 331     memset( p_smooth, 0, sizeof(*p_smooth) * i_src_pitch * i_num_lines );
 332
 333     for( int y = 2; y < i_num_lines - 2; y++ )
 334     {
 335         for( int x = 2; x < i_src_visible - 2; x++ )
 336         {
 337             p_smooth[y*i_src_visible+x] = (uint32_t)(
 338               /* 2 rows up */
 339                 ( p_inpix[(y-2)*i_src_pitch+x-2] )
 340               + ((p_inpix[(y-2)*i_src_pitch+x-1]
 341               +   p_inpix[(y-2)*i_src_pitch+x]
 342               +   p_inpix[(y-2)*i_src_pitch+x+1])<<1 )
 343               + ( p_inpix[(y-2)*i_src_pitch+x+2] )
 344               /* 1 row up */
 345               + ((p_inpix[(y-1)*i_src_pitch+x-2]
 346               + ( p_inpix[(y-1)*i_src_pitch+x-1]<<1 )
 347               + ( p_inpix[(y-1)*i_src_pitch+x]*3 )
 348               + ( p_inpix[(y-1)*i_src_pitch+x+1]<<1 )
 349               +   p_inpix[(y-1)*i_src_pitch+x+2]
 350               /* */
 351               +   p_inpix[y*i_src_pitch+x-2]
 352               + ( p_inpix[y*i_src_pitch+x-1]*3 )
 353               + ( p_inpix[y*i_src_pitch+x]<<2 )
 354               + ( p_inpix[y*i_src_pitch+x+1]*3 )
 355               +   p_inpix[y*i_src_pitch+x+2]
 356               /* 1 row down */
 357               +   p_inpix[(y+1)*i_src_pitch+x-2]
 358               + ( p_inpix[(y+1)*i_src_pitch+x-1]<<1 )
 359               + ( p_inpix[(y+1)*i_src_pitch+x]*3 )
 360               + ( p_inpix[(y+1)*i_src_pitch+x+1]<<1 )
 361               +   p_inpix[(y+1)*i_src_pitch+x+2] )<<1 )
 362               /* 2 rows down */
 363               + ( p_inpix[(y+2)*i_src_pitch+x-2] )
 364               + ((p_inpix[(y+2)*i_src_pitch+x-1]
 365               +   p_inpix[(y+2)*i_src_pitch+x]
 366               +   p_inpix[(y+2)*i_src_pitch+x+1])<<1 )
 367               + ( p_inpix[(y+2)*i_src_pitch+x+2] )
 368               ) >> 6 /* 115 */;
 369         }
 370     }
 371 }
 372
 373 /*****************************************************************************
 374  *
 375  *****************************************************************************/
 376 static int FindShapes( uint32_t *p_diff, uint32_t *p_smooth,
 377                        int i_pitch, int i_visible, int i_lines,
 378                        int *colors,
 379                        int *color_x_min, int *color_x_max,
 380                        int *color_y_min, int *color_y_max )
 381 {
 382     int last = 1;
 383
 384     /**
 385      * Apply some smoothing to remove noise
 386      */
 387     GaussianConvolution( p_diff, p_smooth, i_pitch, i_lines, i_visible );
 388
 389     /**
 390      * Label the shapes and build the labels dependencies list
 391      */
 392     for( int j = 0; j < i_pitch; j++ )
 393     {
 394         p_smooth[j] = 0;
 395         p_smooth[(i_lines-1)*i_pitch+j] = 0;
 396     }
 397     for( int i = 1; i < i_lines-1; i++ )
 398     {
 399         int j;
 400         p_smooth[i*i_pitch] = 0;
 401         for( j = 1; j < i_pitch-1; j++ )
 402         {
 403             if( p_smooth[i*i_pitch+j] > 15 )
 404             {
 405                 if( p_smooth[(i-1)*i_pitch+j-1] )
 406                 {
 407                     p_smooth[i*i_pitch+j] = p_smooth[(i-1)*i_pitch+j-1];
 408                 }
 409                 else if( p_smooth[(i-1)*i_pitch+j] )
 410                     p_smooth[i*i_pitch+j] = p_smooth[(i-1)*i_pitch+j];
 411                 else if( p_smooth[i*i_pitch+j-1] )
 412                     p_smooth[i*i_pitch+j] = p_smooth[i*i_pitch+j-1];
 413                 else
 414                 {
 415                     if( last < NUM_COLORS )
 416                     {
 417                         p_smooth[i*i_pitch+j] = last;
 418                         colors[last] = last;
 419                         last++;
 420                     }
 421                 }
 422                 #define CHECK( A ) \
 423                 if( p_smooth[A] && p_smooth[A] != p_smooth[i*i_pitch+j] ) \
 424                 { \
 425                     if( p_smooth[A] < p_smooth[i*i_pitch+j] ) \
 426                         colors[p_smooth[i*i_pitch+j]] = p_smooth[A]; \
 427                     else \
 428                         colors[p_smooth[A]] = p_smooth[i*i_pitch+j]; \
 429                 }
 430                 CHECK( i*i_pitch+j-1 );
 431                 CHECK( (i-1)*i_pitch+j-1 );
 432                 CHECK( (i-1)*i_pitch+j );
 433                 CHECK( (i-1)*i_pitch+j+1 );
 434                 #undef CHECK
 435             }
 436             else
 437             {
 438                 p_smooth[i*i_pitch+j] = 0;
 439             }
 440         }
 441         p_smooth[i*i_pitch+j] = 0;
 442     }
 443
 444     /**
 445      * Initialise empty rectangle list
 446      */
 447     for( int i = 1; i < last; i++ )
 448     {
 449         color_x_min[i] = -1;
 450         color_x_max[i] = -1;
 451         color_y_min[i] = -1;
 452         color_y_max[i] = -1;
 453     }
 454
 455     /**
 456      * Compute rectangle coordinates
 457      */
 458     for( int i = 0; i < i_pitch * i_lines; i++ )
 459     {
 460         if( p_smooth[i] )
 461         {
 462             while( colors[p_smooth[i]] != (int)p_smooth[i] )
 463                 p_smooth[i] = colors[p_smooth[i]];
 464             if( color_x_min[p_smooth[i]] == -1 )
 465             {
 466                 color_x_min[p_smooth[i]] =
 467                 color_x_max[p_smooth[i]] = i % i_pitch;
 468                 color_y_min[p_smooth[i]] =
 469                 color_y_max[p_smooth[i]] = i / i_pitch;
 470             }
 471             else
 472             {
 473                 int x = i % i_pitch, y = i / i_pitch;
 474                 if( x < color_x_min[p_smooth[i]] )
 475                     color_x_min[p_smooth[i]] = x;
 476                 if( x > color_x_max[p_smooth[i]] )
 477                     color_x_max[p_smooth[i]] = x;
 478                 if( y < color_y_min[p_smooth[i]] )
 479                     color_y_min[p_smooth[i]] = y;
 480                 if( y > color_y_max[p_smooth[i]] )
 481                     color_y_max[p_smooth[i]] = y;
 482             }
 483         }
 484     }
 485
 486     /**
 487      * Merge overlaping rectangles
 488      */
 489     for( int i = 1; i < last; i++ )
 490     {
 491         if( colors[i] != i ) continue;
 492         if( color_x_min[i] == -1 ) continue;
 493         for( int j = i+1; j < last; j++ )
 494         {
 495             if( colors[j] != j ) continue;
 496             if( color_x_min[j] == -1 ) continue;
 497             if( __MAX( color_x_min[i], color_x_min[j] ) < __MIN( color_x_max[i], color_x_max[j] ) &&
 498                 __MAX( color_y_min[i], color_y_min[j] ) < __MIN( color_y_max[i], color_y_max[j] ) )
 499             {
 500                 color_x_min[i] = __MIN( color_x_min[i], color_x_min[j] );
 501                 color_x_max[i] = __MAX( color_x_max[i], color_x_max[j] );
 502                 color_y_min[i] = __MIN( color_y_min[i], color_y_min[j] );
 503                 color_y_max[i] = __MAX( color_y_max[i], color_y_max[j] );
 504                 color_x_min[j] = -1;
 505                 j = 0;
 506             }
 507         }
 508     }
 509
 510     return last;
 511 }
 512
 513 static void Draw( filter_t *p_filter, uint8_t *p_pix, int i_pix_pitch, int i_pix_size )
 514 {
 515     filter_sys_t *p_sys = p_filter->p_sys;
 516
 517     int j = 0;
 518
 519     for( int i = 1; i < p_sys->i_colors; i++ )
 520     {
 521         int x, y;
 522
 523         if( p_sys->colors[i] != i )
 524             continue;
 525
 526         const int color_x_min = p_sys->color_x_min[i];
 527         const int color_x_max = p_sys->color_x_max[i];
 528         const int color_y_min = p_sys->color_y_min[i];
 529         const int color_y_max = p_sys->color_y_max[i];
 530
 531         if( color_x_min == -1 )
 532             continue;
 533         if( ( color_y_max - color_y_min ) * ( color_x_max - color_x_min ) < 16 )
 534             continue;
 535
 536         j++;
 537
 538         y = color_y_min;
 539         for( x = color_x_min; x <= color_x_max; x++ )
 540             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 541
 542         y = color_y_max;
 543         for( x = color_x_min; x <= color_x_max; x++ )
 544             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 545
 546         x = color_x_min;
 547         for( y = color_y_min; y <= color_y_max; y++ )
 548             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 549
 550         x = color_x_max;
 551         for( y = color_y_min; y <= color_y_max; y++ )
 552             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 553     }
 554     msg_Dbg( p_filter, "Counted %d moving shapes.", j );
 555 }