git.sesse.net Git - vlc/blob - modules/video_output/snapshot.c

   1 /*****************************************************************************
   2  * snapshot.c : snapshot plugin for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2002 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Olivier Aubert <oaubert@lisi.univ-lyon1.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 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 General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * This module is a pseudo video output that offers the possibility to
  26  * keep a cache of low-res snapshots.
  27  * The snapshot structure is defined in include/snapshot.h
  28  * In order to access the current snapshot cache, object variables are used:
  29  *   snapshot-list-pointer : the pointer on the first element in the list
  30  *   snapshot-datasize     : size of a snapshot
  31  *                           (also available in snapshot_t->i_datasize)
  32  *   snapshot-cache-size   : size of the cache list
  33  *
  34  * It is used for the moment by the CORBA module and a specialized
  35  * python-vlc binding.
  36  *****************************************************************************/
  37
  38 /*****************************************************************************
  39  * Preamble
  40  *****************************************************************************/
  41
  42 #ifdef HAVE_CONFIG_H
  43 # include "config.h"
  44 #endif
  45
  46 #include <vlc/vlc.h>
  47 #include <vlc_plugin.h>
  48 #include <vlc_vout.h>
  49 #include <vlc_interface.h>
  50 #include <vlc_input.h>
  51
  52 /*****************************************************************************
  53  * Local prototypes
  54  *****************************************************************************/
  55 static int  Create    ( vlc_object_t * );
  56 static void Destroy   ( vlc_object_t * );
  57
  58 static int  Init      ( vout_thread_t * );
  59 static void End       ( vout_thread_t * );
  60 static void Display   ( vout_thread_t *, picture_t * );
  61
  62 /*****************************************************************************
  63  * Module descriptor
  64  *****************************************************************************/
  65 #define WIDTH_TEXT N_( "Snapshot width" )
  66 #define WIDTH_LONGTEXT N_( "Width of the snapshot image." )
  67
  68 #define HEIGHT_TEXT N_( "Snapshot height" )
  69 #define HEIGHT_LONGTEXT N_( "Height of the snapshot image." )
  70
  71 #define CHROMA_TEXT N_( "Chroma" )
  72 #define CHROMA_LONGTEXT N_( "Output chroma for the snapshot image " \
  73                             "(a 4 character string, like \"RV32\")." )
  74
  75 #define CACHE_TEXT N_( "Cache size (number of images)" )
  76 #define CACHE_LONGTEXT N_( "Snapshot cache size (number of images to keep)." )
  77
  78
  79 vlc_module_begin( );
  80     set_description( _( "Snapshot module" ) );
  81     set_shortname( _("Snapshot") );
  82
  83     set_category( CAT_VIDEO );
  84     set_subcategory( SUBCAT_VIDEO_VOUT );
  85     set_capability( "video output", 1 );
  86
  87     add_integer( "snapshot-width", 320, NULL, WIDTH_TEXT, WIDTH_LONGTEXT, false );
  88     add_integer( "snapshot-height", 200, NULL, HEIGHT_TEXT, HEIGHT_LONGTEXT, false );
  89     add_string( "snapshot-chroma", "RV32", NULL, CHROMA_TEXT, CHROMA_LONGTEXT, true );
  90     add_integer( "snapshot-cache-size", 50, NULL, CACHE_TEXT, CACHE_LONGTEXT, true );
  91
  92     set_callbacks( Create, Destroy );
  93 vlc_module_end();
  94
  95 /*****************************************************************************
  96  * vout_sys_t: video output descriptor
  97  *****************************************************************************/
  98 struct vout_sys_t
  99 {
 100     snapshot_t **p_list;    /* List of available snapshots */
 101     int i_index;            /* Index of the next available list member */
 102     int i_size;             /* Size of the cache */
 103     int i_datasize;         /* Size of an image */
 104     input_thread_t *p_input;             /* The input thread */
 105 };
 106
 107 /*****************************************************************************
 108  * Create: allocates video thread
 109  *****************************************************************************
 110  * This function allocates and initializes a vout method.
 111  *****************************************************************************/
 112 static int Create( vlc_object_t *p_this )
 113 {
 114     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 115
 116     /* Allocate instance and initialize some members */
 117     p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
 118     if( ! p_vout->p_sys )
 119         return VLC_ENOMEM;
 120
 121     var_Create( p_vout, "snapshot-width", VLC_VAR_INTEGER );
 122     var_Create( p_vout, "snapshot-height", VLC_VAR_INTEGER );
 123     var_Create( p_vout, "snapshot-datasize", VLC_VAR_INTEGER );
 124     var_Create( p_vout, "snapshot-cache-size", VLC_VAR_INTEGER );
 125     var_Create( p_vout, "snapshot-list-pointer", VLC_VAR_ADDRESS );
 126
 127     p_vout->pf_init = Init;
 128     p_vout->pf_end = End;
 129     p_vout->pf_manage = NULL;
 130     p_vout->pf_render = NULL;
 131     p_vout->pf_display = Display;
 132
 133     return VLC_SUCCESS;
 134 }
 135
 136 /*****************************************************************************
 137  * Init: initialize video thread
 138  *****************************************************************************/
 139 static int Init( vout_thread_t *p_vout )
 140 {
 141     int i_index;
 142     picture_t *p_pic;
 143     vlc_value_t val;
 144     char* psz_chroma;
 145     int i_chroma;
 146     int i_width;
 147     int i_height;
 148     int i_datasize;
 149
 150     i_width  = config_GetInt( p_vout, "snapshot-width" );
 151     i_height = config_GetInt( p_vout, "snapshot-height" );
 152
 153     psz_chroma = config_GetPsz( p_vout, "snapshot-chroma" );
 154     if( psz_chroma )
 155     {
 156         if( strlen( psz_chroma ) < 4 )
 157         {
 158             msg_Err( p_vout, "snapshot-chroma should be 4 characters long" );
 159             return VLC_EGENERIC;
 160         }
 161         i_chroma = VLC_FOURCC( psz_chroma[0], psz_chroma[1],
 162                                psz_chroma[2], psz_chroma[3] );
 163         free( psz_chroma );
 164     }
 165     else
 166     {
 167         msg_Err( p_vout, "Cannot find chroma information." );
 168         return VLC_EGENERIC;
 169     }
 170
 171     I_OUTPUTPICTURES = 0;
 172
 173     /* Initialize the output structure */
 174     p_vout->output.i_chroma = i_chroma;
 175     p_vout->output.pf_setpalette = NULL;
 176     p_vout->output.i_width = i_width;
 177     p_vout->output.i_height = i_height;
 178     p_vout->output.i_aspect = p_vout->output.i_width
 179                                * VOUT_ASPECT_FACTOR / p_vout->output.i_height;
 180
 181
 182     /* Define the bitmasks */
 183     switch( i_chroma )
 184     {
 185       case VLC_FOURCC( 'R','V','1','5' ):
 186         p_vout->output.i_rmask = 0x001f;
 187         p_vout->output.i_gmask = 0x03e0;
 188         p_vout->output.i_bmask = 0x7c00;
 189         break;
 190
 191       case VLC_FOURCC( 'R','V','1','6' ):
 192         p_vout->output.i_rmask = 0x001f;
 193         p_vout->output.i_gmask = 0x07e0;
 194         p_vout->output.i_bmask = 0xf800;
 195         break;
 196
 197       case VLC_FOURCC( 'R','V','2','4' ):
 198         p_vout->output.i_rmask = 0xff0000;
 199         p_vout->output.i_gmask = 0x00ff00;
 200         p_vout->output.i_bmask = 0x0000ff;
 201         break;
 202
 203       case VLC_FOURCC( 'R','V','3','2' ):
 204         p_vout->output.i_rmask = 0xff0000;
 205         p_vout->output.i_gmask = 0x00ff00;
 206         p_vout->output.i_bmask = 0x0000ff;
 207         break;
 208     }
 209
 210     /* Try to initialize 1 direct buffer */
 211     p_pic = NULL;
 212
 213     /* Find an empty picture slot */
 214     for( i_index = 0 ; i_index < VOUT_MAX_PICTURES ; i_index++ )
 215     {
 216         if( p_vout->p_picture[ i_index ].i_status == FREE_PICTURE )
 217         {
 218             p_pic = p_vout->p_picture + i_index;
 219             break;
 220         }
 221     }
 222
 223     /* Allocate the picture */
 224     if( p_pic == NULL )
 225     {
 226         return VLC_SUCCESS;
 227     }
 228
 229     vout_AllocatePicture( VLC_OBJECT(p_vout), p_pic, p_vout->output.i_chroma,
 230                           p_vout->output.i_width, p_vout->output.i_height,
 231                           p_vout->output.i_aspect );
 232
 233     if( p_pic->i_planes == 0 )
 234     {
 235         return VLC_EGENERIC;
 236     }
 237
 238     p_pic->i_status = DESTROYED_PICTURE;
 239     p_pic->i_type   = DIRECT_PICTURE;
 240
 241     PP_OUTPUTPICTURE[ I_OUTPUTPICTURES ] = p_pic;
 242
 243     I_OUTPUTPICTURES++;
 244
 245
 246     /* Get datasize and set variables */
 247     i_datasize = i_width * i_height * p_pic->p->i_pixel_pitch;
 248
 249     p_vout->p_sys->i_datasize = i_datasize;
 250     p_vout->p_sys->i_index = 0;
 251     p_vout->p_sys->i_size = config_GetInt( p_vout, "snapshot-cache-size" );
 252
 253     if( p_vout->p_sys->i_size < 2 )
 254     {
 255         msg_Err( p_vout, "snapshot-cache-size must be at least 1." );
 256         return VLC_EGENERIC;
 257     }
 258
 259     p_vout->p_sys->p_list = malloc( p_vout->p_sys->i_size * sizeof( snapshot_t * ) );
 260
 261     if( p_vout->p_sys->p_list == NULL )
 262         return VLC_ENOMEM;
 263
 264     /* Initialize the structures for the circular buffer */
 265     for( i_index = 0; i_index < p_vout->p_sys->i_size; i_index++ )
 266     {
 267         snapshot_t *p_snapshot = malloc( sizeof( snapshot_t ) );
 268
 269         if( p_snapshot == NULL )
 270             return VLC_ENOMEM;
 271
 272         p_snapshot->i_width = i_width;
 273         p_snapshot->i_height = i_height;
 274         p_snapshot->i_datasize = i_datasize;
 275         p_snapshot->date = 0;
 276         p_snapshot->p_data = ( char* ) malloc( i_datasize );
 277         if( p_snapshot->p_data == NULL )
 278             return VLC_ENOMEM;
 279         p_vout->p_sys->p_list[i_index] = p_snapshot;
 280     }
 281
 282     val.i_int = i_width;
 283     var_Set( p_vout, "snapshot-width", val );
 284     val.i_int = i_height;
 285     var_Set( p_vout, "snapshot-height", val );
 286     val.i_int = i_datasize;
 287     var_Set( p_vout, "snapshot-datasize", val );
 288
 289     val.i_int = p_vout->p_sys->i_size;
 290     var_Set( p_vout, "snapshot-cache-size", val );
 291
 292     val.p_address = p_vout->p_sys->p_list;
 293     var_Set( p_vout, "snapshot-list-pointer", val );
 294
 295     /* Get the p_input pointer (to access video times) */
 296     p_vout->p_sys->p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT,
 297                                               FIND_PARENT );
 298
 299     if( !p_vout->p_sys->p_input )
 300         return VLC_ENOOBJ;
 301
 302     if( var_Create( p_vout->p_sys->p_input, "snapshot-id", VLC_VAR_INTEGER ) )
 303     {
 304         msg_Err( p_vout, "Cannot create snapshot-id variable in p_input (%d).",
 305                  p_vout->p_sys->p_input->i_object_id );
 306         return VLC_EGENERIC;
 307     }
 308
 309     /* Register the snapshot vout module at the input level */
 310     val.i_int = p_vout->i_object_id;
 311
 312     if( var_Set( p_vout->p_sys->p_input, "snapshot-id", val ) )
 313     {
 314         msg_Err( p_vout, "Cannot register snapshot-id in p_input (%d).",
 315                  p_vout->p_sys->p_input->i_object_id );
 316         return VLC_EGENERIC;
 317     }
 318
 319     return VLC_SUCCESS;
 320 }
 321
 322 /*****************************************************************************
 323  * End: terminate video thread output method
 324  *****************************************************************************/
 325 static void End( vout_thread_t *p_vout )
 326 {
 327     (void)p_vout;
 328 }
 329
 330 /*****************************************************************************
 331  * Destroy: destroy video thread
 332  *****************************************************************************
 333  * Terminate an output method created by Create
 334  *****************************************************************************/
 335 static void Destroy( vlc_object_t *p_this )
 336 {
 337     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 338     int i_index;
 339
 340     var_Destroy( p_vout->p_sys->p_input, "snapshot-id" );
 341
 342     vlc_object_release( p_vout->p_sys->p_input );
 343     var_Destroy( p_this, "snapshot-width" );
 344     var_Destroy( p_this, "snapshot-height" );
 345     var_Destroy( p_this, "snapshot-datasize" );
 346
 347     for( i_index = 0 ; i_index < p_vout->p_sys->i_size ; i_index++ )
 348     {
 349         free( p_vout->p_sys->p_list[ i_index ]->p_data );
 350     }
 351     free( p_vout->p_sys->p_list );
 352     /* Destroy structure */
 353     free( p_vout->p_sys );
 354 }
 355
 356 /* Return the position in ms from the start of the movie */
 357 static mtime_t snapshot_GetMovietime( vout_thread_t *p_vout )
 358 {
 359     input_thread_t* p_input;
 360     vlc_value_t val;
 361     mtime_t i_result;
 362
 363     p_input = p_vout->p_sys->p_input;
 364     if( !p_input )
 365         return 0;
 366
 367     var_Get( p_input, "time", &val );
 368
 369     i_result = val.i_time - p_input->i_pts_delay;
 370
 371     return( i_result / 1000 );
 372 }
 373
 374 /*****************************************************************************
 375  * Display: displays previously rendered output
 376  *****************************************************************************
 377  * This function copies the rendered picture into our circular buffer.
 378  *****************************************************************************/
 379 static void Display( vout_thread_t *p_vout, picture_t *p_pic )
 380 {
 381     int i_index;
 382     mtime_t i_date;
 383
 384     i_index = p_vout->p_sys->i_index;
 385
 386     vlc_memcpy( p_vout->p_sys->p_list[i_index]->p_data, p_pic->p->p_pixels,
 387                 p_vout->p_sys->i_datasize );
 388
 389     i_date = snapshot_GetMovietime( p_vout );
 390
 391     p_vout->p_sys->p_list[i_index]->date = i_date;
 392
 393     i_index++;
 394
 395     if( i_index >= p_vout->p_sys->i_size )
 396     {
 397         i_index = 0;
 398     }
 399
 400     p_vout->p_sys->i_index = i_index;
 401 }
 402