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  * $Id$
   6  *
   7  * Authors: Antoine Cellerier <dionoea -at- videolan -dot- org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_sout.h>
  35 #include <vlc_filter.h>
  36 #include <vlc_picture.h>
  37 #include "filter_picture.h"
  38
  39 /*****************************************************************************
  40  * Module descriptor
  41  *****************************************************************************/
  42 static int  Create    ( vlc_object_t * );
  43 static void Destroy   ( vlc_object_t * );
  44
  45 #define FILTER_PREFIX "motiondetect-"
  46
  47 vlc_module_begin ()
  48     set_description( N_("Motion detect video filter") )
  49     set_shortname( N_( "Motion Detect" ))
  50     set_category( CAT_VIDEO )
  51     set_subcategory( SUBCAT_VIDEO_VFILTER )
  52     set_capability( "video filter", 0 )
  53
  54     add_shortcut( "motion" )
  55     set_callbacks( Create, Destroy )
  56 vlc_module_end ()
  57
  58
  59 /*****************************************************************************
  60  * Local prototypes
  61  *****************************************************************************/
  62 static picture_t *Filter( filter_t *, picture_t * );
  63 static void GaussianConvolution( uint32_t *, uint32_t *, int, int, int );
  64 static int FindShapes( uint32_t *, uint32_t *, int, int, int,
  65                        int *, int *, int *, int *, int *);
  66 static void Draw( filter_t *p_filter, uint8_t *p_pix, int i_pix_pitch, int i_pix_size );
  67 #define NUM_COLORS (5000)
  68
  69 struct filter_sys_t
  70 {
  71     bool is_yuv_planar;
  72     bool b_old;
  73     picture_t *p_old;
  74     uint32_t *p_buf;
  75     uint32_t *p_buf2;
  76
  77     /* */
  78     int i_colors;
  79     int colors[NUM_COLORS];
  80     int color_x_min[NUM_COLORS];
  81     int color_x_max[NUM_COLORS];
  82     int color_y_min[NUM_COLORS];
  83     int color_y_max[NUM_COLORS];
  84 };
  85
  86 /*****************************************************************************
  87  * Create
  88  *****************************************************************************/
  89 static int Create( vlc_object_t *p_this )
  90 {
  91     filter_t *p_filter = (filter_t *)p_this;
  92     const video_format_t *p_fmt = &p_filter->fmt_in.video;
  93     filter_sys_t *p_sys;
  94     bool is_yuv_planar;
  95
  96     switch( p_fmt->i_chroma )
  97     {
  98         CASE_PLANAR_YUV
  99             is_yuv_planar = true;
 100             break;
 101
 102         CASE_PACKED_YUV_422
 103             is_yuv_planar = false;
 104             break;
 105
 106         default:
 107             msg_Err( p_filter, "Unsupported input chroma (%4.4s)",
 108                      (char*)&(p_fmt->i_chroma) );
 109             return VLC_EGENERIC;
 110     }
 111     p_filter->pf_video_filter = Filter;
 112
 113     /* Allocate structure */
 114     p_filter->p_sys = p_sys = malloc( sizeof( filter_sys_t ) );
 115     if( p_filter->p_sys == NULL )
 116         return VLC_ENOMEM;
 117
 118     p_sys->is_yuv_planar = is_yuv_planar;
 119     p_sys->b_old = false;
 120     p_sys->p_old = picture_NewFromFormat( p_fmt );
 121     p_sys->p_buf  = calloc( p_fmt->i_width * p_fmt->i_height, sizeof(*p_sys->p_buf) );
 122     p_sys->p_buf2 = calloc( p_fmt->i_width * p_fmt->i_height, sizeof(*p_sys->p_buf) );
 123
 124     if( !p_sys->p_old || !p_sys->p_buf || !p_sys->p_buf2 )
 125     {
 126         free( p_sys->p_buf2 );
 127         free( p_sys->p_buf );
 128         if( p_sys->p_old )
 129             picture_Release( p_sys->p_old );
 130         return VLC_ENOMEM;
 131     }
 132
 133     return VLC_SUCCESS;
 134 }
 135
 136 /*****************************************************************************
 137  * Destroy
 138  *****************************************************************************/
 139 static void Destroy( vlc_object_t *p_this )
 140 {
 141     filter_t *p_filter = (filter_t *)p_this;
 142     filter_sys_t *p_sys = p_filter->p_sys;
 143
 144     free( p_sys->p_buf2 );
 145     free( p_sys->p_buf );
 146     picture_Release( p_sys->p_old );
 147     free( p_sys );
 148 }
 149
 150
 151 /*****************************************************************************
 152  * Filter YUV Planar/Packed
 153  *****************************************************************************/
 154 static void PreparePlanar( filter_t *p_filter, picture_t *p_inpic )
 155 {
 156     filter_sys_t *p_sys = p_filter->p_sys;
 157     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 158
 159     uint8_t *p_oldpix   = p_sys->p_old->p[Y_PLANE].p_pixels;
 160     const int i_old_pitch = p_sys->p_old->p[Y_PLANE].i_pitch;
 161
 162     const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
 163     const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
 164
 165     /**
 166      * Substract Y planes
 167      */
 168     for( unsigned y = 0; y < p_fmt->i_height; y++ )
 169     {
 170         for( unsigned x = 0; x < p_fmt->i_width; x++ )
 171             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] );
 172     }
 173
 174     int i_chroma_dx;
 175     int i_chroma_dy;
 176     switch( p_inpic->format.i_chroma )
 177     {
 178         case VLC_CODEC_I420:
 179         case VLC_CODEC_J420:
 180         case VLC_CODEC_YV12:
 181             i_chroma_dx = 2;
 182             i_chroma_dy = 2;
 183             break;
 184
 185         case VLC_CODEC_I422:
 186         case VLC_CODEC_J422:
 187             i_chroma_dx = 2;
 188             i_chroma_dy = 1;
 189             break;
 190
 191         default:
 192             msg_Warn( p_filter, "Not taking chroma into account" );
 193             return;
 194     }
 195
 196     const uint8_t *p_inpix_u = p_inpic->p[U_PLANE].p_pixels;
 197     const uint8_t *p_inpix_v = p_inpic->p[V_PLANE].p_pixels;
 198     const int i_src_pitch_u = p_inpic->p[U_PLANE].i_pitch;
 199     const int i_src_pitch_v = p_inpic->p[V_PLANE].i_pitch;
 200
 201     const uint8_t *p_oldpix_u = p_sys->p_old->p[U_PLANE].p_pixels;
 202     const uint8_t *p_oldpix_v = p_sys->p_old->p[V_PLANE].p_pixels;
 203     const int i_old_pitch_u = p_sys->p_old->p[U_PLANE].i_pitch;
 204     const int i_old_pitch_v = p_sys->p_old->p[V_PLANE].i_pitch;
 205
 206     for( unsigned y = 0; y < p_fmt->i_height/i_chroma_dy; y++ )
 207     {
 208         for( unsigned x = 0; x < p_fmt->i_width/i_chroma_dx; x ++ )
 209         {
 210             const int d = abs( p_inpix_u[y*i_src_pitch_u+x] - p_oldpix_u[y*i_old_pitch_u+x] ) +
 211                           abs( p_inpix_v[y*i_src_pitch_v+x] - p_oldpix_v[y*i_old_pitch_v+x] );
 212
 213             for( int j = 0; j < i_chroma_dy; j++ )
 214             {
 215                 for( int i = 0; i < i_chroma_dx; i++ )
 216                     p_sys->p_buf2[i_chroma_dy*p_fmt->i_width*j + i_chroma_dx*i] = d;
 217             }
 218         }
 219     }
 220 }
 221
 222 static int PreparePacked( filter_t *p_filter, picture_t *p_inpic, int *pi_pix_offset )
 223 {
 224     filter_sys_t *p_sys = p_filter->p_sys;
 225     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 226
 227     int i_y_offset, i_u_offset, i_v_offset;
 228     if( GetPackedYuvOffsets( p_fmt->i_chroma,
 229                              &i_y_offset, &i_u_offset, &i_v_offset ) )
 230     {
 231         msg_Warn( p_filter, "Unsupported input chroma (%4.4s)",
 232                   (char*)&p_fmt->i_chroma );
 233         return VLC_EGENERIC;
 234     }
 235     *pi_pix_offset = i_y_offset;
 236
 237     /* Substract all planes at once */
 238     uint8_t *p_oldpix   = p_sys->p_old->p[Y_PLANE].p_pixels;
 239     const int i_old_pitch = p_sys->p_old->p[Y_PLANE].i_pitch;
 240
 241     const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
 242     const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
 243
 244     for( unsigned y = 0; y < p_fmt->i_height; y++ )
 245     {
 246         for( unsigned x = 0; x < p_fmt->i_width; x+=2 )
 247         {
 248             int d;
 249             d = abs( p_inpix[y*i_src_pitch+2*x+i_u_offset] - p_oldpix[y*i_old_pitch+2*x+i_u_offset] ) +
 250                 abs( p_inpix[y*i_src_pitch+2*x+i_v_offset] - p_oldpix[y*i_old_pitch+2*x+i_v_offset] );
 251
 252             for( int i = 0; i < 2; i++ )
 253                 p_sys->p_buf2[y*p_fmt->i_width+x+i] =
 254                     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;
 255         }
 256     }
 257     return VLC_SUCCESS;
 258 }
 259
 260 static picture_t *Filter( filter_t *p_filter, picture_t *p_inpic )
 261 {
 262     filter_sys_t *p_sys = p_filter->p_sys;
 263
 264     if( !p_inpic )
 265         return NULL;
 266
 267     picture_t *p_outpic = filter_NewPicture( p_filter );
 268     if( !p_outpic )
 269     {
 270         picture_Release( p_inpic );
 271         return NULL;
 272     }
 273     picture_Copy( p_outpic, p_inpic );
 274
 275     if( !p_sys->b_old )
 276     {
 277         picture_Copy( p_sys->p_old, p_inpic );
 278         p_sys->b_old = true;
 279         goto exit;
 280     }
 281
 282     int i_pix_offset;
 283     int i_pix_size;
 284     if( p_sys->is_yuv_planar )
 285     {
 286         PreparePlanar( p_filter, p_inpic );
 287         i_pix_offset = 0;
 288         i_pix_size = 1;
 289     }
 290     else
 291     {
 292         if( PreparePacked( p_filter, p_inpic, &i_pix_offset ) )
 293             goto exit;
 294         i_pix_size = 2;
 295     }
 296
 297     /**
 298      * Get the areas where movement was detected
 299      */
 300     const video_format_t *p_fmt = &p_filter->fmt_in.video;
 301     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,
 302                                   p_sys->colors, p_sys->color_x_min, p_sys->color_x_max, p_sys->color_y_min, p_sys->color_y_max );
 303
 304     /**
 305      * Count final number of shapes
 306      * Draw rectangles (there can be more than 1 moving shape in 1 rectangle)
 307      */
 308     Draw( p_filter, &p_outpic->p[Y_PLANE].p_pixels[i_pix_offset], p_outpic->p[Y_PLANE].i_pitch, i_pix_size );
 309
 310     /**
 311      * We're done. Lets keep a copy of the picture
 312      * TODO we may just picture_Release with a latency of 1 if the filters/vout
 313      * handle it correctly */
 314     picture_Copy( p_sys->p_old, p_inpic );
 315
 316 exit:
 317     picture_Release( p_inpic );
 318     return p_outpic;
 319 }
 320
 321
 322 /*****************************************************************************
 323  * Gaussian Convolution
 324  *****************************************************************************
 325  *    Gaussian convolution ( sigma == 1.4 )
 326  *
 327  *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 328  *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 329  *    |  5 12 15 12  5  | ~ |  4 12 16 12  4 |
 330  *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 331  *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 332  *****************************************************************************/
 333 static void GaussianConvolution( uint32_t *p_inpix, uint32_t *p_smooth,
 334                                  int i_src_pitch, int i_num_lines,
 335                                  int i_src_visible )
 336 {
 337     /* A bit overkill but ... simpler */
 338     memset( p_smooth, 0, sizeof(*p_smooth) * i_src_pitch * i_num_lines );
 339
 340     for( int y = 2; y < i_num_lines - 2; y++ )
 341     {
 342         for( int x = 2; x < i_src_visible - 2; x++ )
 343         {
 344             p_smooth[y*i_src_visible+x] = (uint32_t)(
 345               /* 2 rows up */
 346                 ( p_inpix[(y-2)*i_src_pitch+x-2] )
 347               + ((p_inpix[(y-2)*i_src_pitch+x-1]
 348               +   p_inpix[(y-2)*i_src_pitch+x]
 349               +   p_inpix[(y-2)*i_src_pitch+x+1])<<1 )
 350               + ( p_inpix[(y-2)*i_src_pitch+x+2] )
 351               /* 1 row up */
 352               + ((p_inpix[(y-1)*i_src_pitch+x-2]
 353               + ( p_inpix[(y-1)*i_src_pitch+x-1]<<1 )
 354               + ( p_inpix[(y-1)*i_src_pitch+x]*3 )
 355               + ( p_inpix[(y-1)*i_src_pitch+x+1]<<1 )
 356               +   p_inpix[(y-1)*i_src_pitch+x+2]
 357               /* */
 358               +   p_inpix[y*i_src_pitch+x-2]
 359               + ( p_inpix[y*i_src_pitch+x-1]*3 )
 360               + ( p_inpix[y*i_src_pitch+x]<<2 )
 361               + ( p_inpix[y*i_src_pitch+x+1]*3 )
 362               +   p_inpix[y*i_src_pitch+x+2]
 363               /* 1 row down */
 364               +   p_inpix[(y+1)*i_src_pitch+x-2]
 365               + ( p_inpix[(y+1)*i_src_pitch+x-1]<<1 )
 366               + ( p_inpix[(y+1)*i_src_pitch+x]*3 )
 367               + ( p_inpix[(y+1)*i_src_pitch+x+1]<<1 )
 368               +   p_inpix[(y+1)*i_src_pitch+x+2] )<<1 )
 369               /* 2 rows down */
 370               + ( p_inpix[(y+2)*i_src_pitch+x-2] )
 371               + ((p_inpix[(y+2)*i_src_pitch+x-1]
 372               +   p_inpix[(y+2)*i_src_pitch+x]
 373               +   p_inpix[(y+2)*i_src_pitch+x+1])<<1 )
 374               + ( p_inpix[(y+2)*i_src_pitch+x+2] )
 375               ) >> 6 /* 115 */;
 376         }
 377     }
 378 }
 379
 380 /*****************************************************************************
 381  *
 382  *****************************************************************************/
 383 static int FindShapes( uint32_t *p_diff, uint32_t *p_smooth,
 384                        int i_pitch, int i_visible, int i_lines,
 385                        int *colors,
 386                        int *color_x_min, int *color_x_max,
 387                        int *color_y_min, int *color_y_max )
 388 {
 389     int last = 1;
 390
 391     /**
 392      * Apply some smoothing to remove noise
 393      */
 394     GaussianConvolution( p_diff, p_smooth, i_pitch, i_lines, i_visible );
 395
 396     /**
 397      * Label the shapes and build the labels dependencies list
 398      */
 399     for( int j = 0; j < i_pitch; j++ )
 400     {
 401         p_smooth[j] = 0;
 402         p_smooth[(i_lines-1)*i_pitch+j] = 0;
 403     }
 404     for( int i = 1; i < i_lines-1; i++ )
 405     {
 406         int j;
 407         p_smooth[i*i_pitch] = 0;
 408         for( j = 1; j < i_pitch-1; j++ )
 409         {
 410             if( p_smooth[i*i_pitch+j] > 15 )
 411             {
 412                 if( p_smooth[(i-1)*i_pitch+j-1] )
 413                 {
 414                     p_smooth[i*i_pitch+j] = p_smooth[(i-1)*i_pitch+j-1];
 415                 }
 416                 else if( p_smooth[(i-1)*i_pitch+j] )
 417                     p_smooth[i*i_pitch+j] = p_smooth[(i-1)*i_pitch+j];
 418                 else if( p_smooth[i*i_pitch+j-1] )
 419                     p_smooth[i*i_pitch+j] = p_smooth[i*i_pitch+j-1];
 420                 else
 421                 {
 422                     if( last < NUM_COLORS )
 423                     {
 424                         p_smooth[i*i_pitch+j] = last;
 425                         colors[last] = last;
 426                         last++;
 427                     }
 428                 }
 429                 #define CHECK( A ) \
 430                 if( p_smooth[A] && p_smooth[A] != p_smooth[i*i_pitch+j] ) \
 431                 { \
 432                     if( p_smooth[A] < p_smooth[i*i_pitch+j] ) \
 433                         colors[p_smooth[i*i_pitch+j]] = p_smooth[A]; \
 434                     else \
 435                         colors[p_smooth[A]] = p_smooth[i*i_pitch+j]; \
 436                 }
 437                 CHECK( i*i_pitch+j-1 );
 438                 CHECK( (i-1)*i_pitch+j-1 );
 439                 CHECK( (i-1)*i_pitch+j );
 440                 CHECK( (i-1)*i_pitch+j+1 );
 441                 #undef CHECK
 442             }
 443             else
 444             {
 445                 p_smooth[i*i_pitch+j] = 0;
 446             }
 447         }
 448         p_smooth[i*i_pitch+j] = 0;
 449     }
 450
 451     /**
 452      * Initialise empty rectangle list
 453      */
 454     for( int i = 1; i < last; i++ )
 455     {
 456         color_x_min[i] = -1;
 457         color_x_max[i] = -1;
 458         color_y_min[i] = -1;
 459         color_y_max[i] = -1;
 460     }
 461
 462     /**
 463      * Compute rectangle coordinates
 464      */
 465     for( int i = 0; i < i_pitch * i_lines; i++ )
 466     {
 467         if( p_smooth[i] )
 468         {
 469             while( colors[p_smooth[i]] != (int)p_smooth[i] )
 470                 p_smooth[i] = colors[p_smooth[i]];
 471             if( color_x_min[p_smooth[i]] == -1 )
 472             {
 473                 color_x_min[p_smooth[i]] =
 474                 color_x_max[p_smooth[i]] = i % i_pitch;
 475                 color_y_min[p_smooth[i]] =
 476                 color_y_max[p_smooth[i]] = i / i_pitch;
 477             }
 478             else
 479             {
 480                 int x = i % i_pitch, y = i / i_pitch;
 481                 if( x < color_x_min[p_smooth[i]] )
 482                     color_x_min[p_smooth[i]] = x;
 483                 if( x > color_x_max[p_smooth[i]] )
 484                     color_x_max[p_smooth[i]] = x;
 485                 if( y < color_y_min[p_smooth[i]] )
 486                     color_y_min[p_smooth[i]] = y;
 487                 if( y > color_y_max[p_smooth[i]] )
 488                     color_y_max[p_smooth[i]] = y;
 489             }
 490         }
 491     }
 492
 493     /**
 494      * Merge overlaping rectangles
 495      */
 496     for( int i = 1; i < last; i++ )
 497     {
 498         if( colors[i] != i ) continue;
 499         if( color_x_min[i] == -1 ) continue;
 500         for( int j = i+1; j < last; j++ )
 501         {
 502             if( colors[j] != j ) continue;
 503             if( color_x_min[j] == -1 ) continue;
 504             if( __MAX( color_x_min[i], color_x_min[j] ) < __MIN( color_x_max[i], color_x_max[j] ) &&
 505                 __MAX( color_y_min[i], color_y_min[j] ) < __MIN( color_y_max[i], color_y_max[j] ) )
 506             {
 507                 color_x_min[i] = __MIN( color_x_min[i], color_x_min[j] );
 508                 color_x_max[i] = __MAX( color_x_max[i], color_x_max[j] );
 509                 color_y_min[i] = __MIN( color_y_min[i], color_y_min[j] );
 510                 color_y_max[i] = __MAX( color_y_max[i], color_y_max[j] );
 511                 color_x_min[j] = -1;
 512                 j = 0;
 513             }
 514         }
 515     }
 516
 517     return last;
 518 }
 519
 520 static void Draw( filter_t *p_filter, uint8_t *p_pix, int i_pix_pitch, int i_pix_size )
 521 {
 522     filter_sys_t *p_sys = p_filter->p_sys;
 523
 524     int j = 0;
 525
 526     for( int i = 1; i < p_sys->i_colors; i++ )
 527     {
 528         int x, y;
 529
 530         if( p_sys->colors[i] != i )
 531             continue;
 532
 533         const int color_x_min = p_sys->color_x_min[i];
 534         const int color_x_max = p_sys->color_x_max[i];
 535         const int color_y_min = p_sys->color_y_min[i];
 536         const int color_y_max = p_sys->color_y_max[i];
 537
 538         if( color_x_min == -1 )
 539             continue;
 540         if( ( color_y_max - color_y_min ) * ( color_x_max - color_x_min ) < 16 )
 541             continue;
 542
 543         j++;
 544
 545         y = color_y_min;
 546         for( x = color_x_min; x <= color_x_max; x++ )
 547             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 548
 549         y = color_y_max;
 550         for( x = color_x_min; x <= color_x_max; x++ )
 551             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 552
 553         x = color_x_min;
 554         for( y = color_y_min; y <= color_y_max; y++ )
 555             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 556
 557         x = color_x_max;
 558         for( y = color_y_min; y <= color_y_max; y++ )
 559             p_pix[y*i_pix_pitch+x*i_pix_size] = 0xff;
 560     }
 561     msg_Dbg( p_filter, "Counted %d moving shapes.", j );
 562 }