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_common.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( N_( "Snapshot output" ) )
  81     set_shortname( N_("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 typedef struct snapshot_t
  99 {
 100   uint8_t *p_data;   /* Data area */
 101
 102   int i_width;       /* In pixels */
 103   int i_height;      /* In pixels */
 104   int i_datasize;    /* In bytes */
 105   mtime_t date;      /* Presentation time */
 106 } snapshot_t;
 107
 108 struct vout_sys_t
 109 {
 110     snapshot_t **p_list;    /* List of available snapshots */
 111     int i_index;            /* Index of the next available list member */
 112     int i_size;             /* Size of the cache */
 113     int i_datasize;         /* Size of an image */
 114     input_thread_t *p_input;             /* The input thread */
 115 };
 116
 117 /*****************************************************************************
 118  * Create: allocates video thread
 119  *****************************************************************************
 120  * This function allocates and initializes a vout method.
 121  *****************************************************************************/
 122 static int Create( vlc_object_t *p_this )
 123 {
 124     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 125
 126     /* Allocate instance and initialize some members */
 127     p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
 128     if( ! p_vout->p_sys )
 129         return VLC_ENOMEM;
 130
 131     var_Create( p_vout, "snapshot-width", VLC_VAR_INTEGER );
 132     var_Create( p_vout, "snapshot-height", VLC_VAR_INTEGER );
 133     var_Create( p_vout, "snapshot-datasize", VLC_VAR_INTEGER );
 134     var_Create( p_vout, "snapshot-cache-size", VLC_VAR_INTEGER );
 135     var_Create( p_vout, "snapshot-list-pointer", VLC_VAR_ADDRESS );
 136
 137     p_vout->pf_init = Init;
 138     p_vout->pf_end = End;
 139     p_vout->pf_manage = NULL;
 140     p_vout->pf_render = NULL;
 141     p_vout->pf_display = Display;
 142
 143     return VLC_SUCCESS;
 144 }
 145
 146 /*****************************************************************************
 147  * Init: initialize video thread
 148  *****************************************************************************/
 149 static int Init( vout_thread_t *p_vout )
 150 {
 151     int i_index;
 152     picture_t *p_pic;
 153     vlc_value_t val;
 154     char* psz_chroma;
 155     int i_chroma;
 156     int i_width;
 157     int i_height;
 158     int i_datasize;
 159
 160     i_width  = config_GetInt( p_vout, "snapshot-width" );
 161     i_height = config_GetInt( p_vout, "snapshot-height" );
 162
 163     psz_chroma = config_GetPsz( p_vout, "snapshot-chroma" );
 164     if( psz_chroma )
 165     {
 166         if( strlen( psz_chroma ) < 4 )
 167         {
 168             msg_Err( p_vout, "snapshot-chroma should be 4 characters long" );
 169             return VLC_EGENERIC;
 170         }
 171         i_chroma = vlc_fourcc_GetCodec( VIDEO_ES,
 172                                         VLC_FOURCC( psz_chroma[0], psz_chroma[1],
 173                                                     psz_chroma[2], psz_chroma[3] ) );
 174         free( psz_chroma );
 175     }
 176     else
 177     {
 178         msg_Err( p_vout, "Cannot find chroma information." );
 179         return VLC_EGENERIC;
 180     }
 181
 182     I_OUTPUTPICTURES = 0;
 183
 184     /* Initialize the output structure */
 185     p_vout->output.i_chroma = i_chroma;
 186     p_vout->output.pf_setpalette = NULL;
 187     p_vout->output.i_width = i_width;
 188     p_vout->output.i_height = i_height;
 189     p_vout->output.i_aspect = p_vout->output.i_width
 190                                * VOUT_ASPECT_FACTOR / p_vout->output.i_height;
 191
 192
 193     /* Define the bitmasks */
 194     switch( i_chroma )
 195     {
 196       case VLC_CODEC_RGB15;
 197         p_vout->output.i_rmask = 0x001f;
 198         p_vout->output.i_gmask = 0x03e0;
 199         p_vout->output.i_bmask = 0x7c00;
 200         break;
 201
 202       case VLC_CODEC_RGB16;
 203         p_vout->output.i_rmask = 0x001f;
 204         p_vout->output.i_gmask = 0x07e0;
 205         p_vout->output.i_bmask = 0xf800;
 206         break;
 207
 208       case VLC_CODEC_RGB24;
 209         p_vout->output.i_rmask = 0xff0000;
 210         p_vout->output.i_gmask = 0x00ff00;
 211         p_vout->output.i_bmask = 0x0000ff;
 212         break;
 213
 214       case VLC_CODEC_RGB32:
 215         p_vout->output.i_rmask = 0xff0000;
 216         p_vout->output.i_gmask = 0x00ff00;
 217         p_vout->output.i_bmask = 0x0000ff;
 218         break;
 219     }
 220
 221     /* Try to initialize 1 direct buffer */
 222     p_pic = NULL;
 223
 224     /* Find an empty picture slot */
 225     for( i_index = 0 ; i_index < VOUT_MAX_PICTURES ; i_index++ )
 226     {
 227         if( p_vout->p_picture[ i_index ].i_status == FREE_PICTURE )
 228         {
 229             p_pic = p_vout->p_picture + i_index;
 230             break;
 231         }
 232     }
 233
 234     /* Allocate the picture */
 235     if( p_pic == NULL )
 236     {
 237         return VLC_SUCCESS;
 238     }
 239
 240     vout_AllocatePicture( VLC_OBJECT(p_vout), p_pic, p_vout->output.i_chroma,
 241                           p_vout->output.i_width, p_vout->output.i_height,
 242                           p_vout->output.i_aspect );
 243
 244     if( p_pic->i_planes == 0 )
 245     {
 246         return VLC_EGENERIC;
 247     }
 248
 249     p_pic->i_status = DESTROYED_PICTURE;
 250     p_pic->i_type   = DIRECT_PICTURE;
 251
 252     PP_OUTPUTPICTURE[ I_OUTPUTPICTURES ] = p_pic;
 253
 254     I_OUTPUTPICTURES++;
 255
 256
 257     /* Get datasize and set variables */
 258     i_datasize = i_width * i_height * p_pic->p->i_pixel_pitch;
 259
 260     p_vout->p_sys->i_datasize = i_datasize;
 261     p_vout->p_sys->i_index = 0;
 262     p_vout->p_sys->i_size = config_GetInt( p_vout, "snapshot-cache-size" );
 263
 264     if( p_vout->p_sys->i_size < 2 )
 265     {
 266         msg_Err( p_vout, "snapshot-cache-size must be at least 1." );
 267         return VLC_EGENERIC;
 268     }
 269
 270     p_vout->p_sys->p_list = malloc( p_vout->p_sys->i_size * sizeof( snapshot_t * ) );
 271
 272     if( p_vout->p_sys->p_list == NULL )
 273         return VLC_ENOMEM;
 274
 275     /* Initialize the structures for the circular buffer */
 276     for( i_index = 0; i_index < p_vout->p_sys->i_size; i_index++ )
 277     {
 278         snapshot_t *p_snapshot = malloc( sizeof( snapshot_t ) );
 279
 280         if( p_snapshot == NULL )
 281             return VLC_ENOMEM;
 282
 283         p_snapshot->i_width = i_width;
 284         p_snapshot->i_height = i_height;
 285         p_snapshot->i_datasize = i_datasize;
 286         p_snapshot->date = 0;
 287         p_snapshot->p_data = malloc( i_datasize );
 288         if( p_snapshot->p_data == NULL )
 289         {
 290             free( p_snapshot );
 291             return VLC_ENOMEM;
 292         }
 293         p_vout->p_sys->p_list[i_index] = p_snapshot;
 294     }
 295
 296     val.i_int = i_width;
 297     var_Set( p_vout, "snapshot-width", val );
 298     val.i_int = i_height;
 299     var_Set( p_vout, "snapshot-height", val );
 300     val.i_int = i_datasize;
 301     var_Set( p_vout, "snapshot-datasize", val );
 302
 303     val.i_int = p_vout->p_sys->i_size;
 304     var_Set( p_vout, "snapshot-cache-size", val );
 305
 306     val.p_address = p_vout->p_sys->p_list;
 307     var_Set( p_vout, "snapshot-list-pointer", val );
 308
 309     /* Get the p_input pointer (to access video times) */
 310     p_vout->p_sys->p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT,
 311                                               FIND_PARENT );
 312
 313     if( !p_vout->p_sys->p_input )
 314         return VLC_ENOOBJ;
 315
 316     if( var_Create( p_vout->p_sys->p_input, "snapshot-id", VLC_VAR_INTEGER ) )
 317     {
 318         msg_Err( p_vout, "Cannot create snapshot-id variable in p_input(%p).",
 319                  p_vout->p_sys->p_input );
 320         return VLC_EGENERIC;
 321     }
 322
 323     /* Register the snapshot vout module at the input level */
 324     val.p_address = p_vout;
 325
 326     if( var_Set( p_vout->p_sys->p_input, "snapshot-id", val ) )
 327     {
 328         msg_Err( p_vout, "Cannot register snapshot-id in p_input(%p).",
 329                  p_vout->p_sys->p_input );
 330         return VLC_EGENERIC;
 331     }
 332
 333     return VLC_SUCCESS;
 334 }
 335
 336 /*****************************************************************************
 337  * End: terminate video thread output method
 338  *****************************************************************************/
 339 static void End( vout_thread_t *p_vout )
 340 {
 341     (void)p_vout;
 342 }
 343
 344 /*****************************************************************************
 345  * Destroy: destroy video thread
 346  *****************************************************************************
 347  * Terminate an output method created by Create
 348  *****************************************************************************/
 349 static void Destroy( vlc_object_t *p_this )
 350 {
 351     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 352     int i_index;
 353
 354     var_Destroy( p_vout->p_sys->p_input, "snapshot-id" );
 355
 356     vlc_object_release( p_vout->p_sys->p_input );
 357     var_Destroy( p_this, "snapshot-width" );
 358     var_Destroy( p_this, "snapshot-height" );
 359     var_Destroy( p_this, "snapshot-datasize" );
 360
 361     for( i_index = 0 ; i_index < p_vout->p_sys->i_size ; i_index++ )
 362     {
 363         free( p_vout->p_sys->p_list[ i_index ]->p_data );
 364     }
 365     free( p_vout->p_sys->p_list );
 366     /* Destroy structure */
 367     free( p_vout->p_sys );
 368 }
 369
 370 /* Return the position in ms from the start of the movie */
 371 static mtime_t snapshot_GetMovietime( vout_thread_t *p_vout )
 372 {
 373     input_thread_t *p_input = p_vout->p_sys->p_input;
 374     if( !p_input )
 375         return 0;
 376
 377     return var_GetTime( p_input, "time" ) / 1000;
 378 }
 379
 380 /*****************************************************************************
 381  * Display: displays previously rendered output
 382  *****************************************************************************
 383  * This function copies the rendered picture into our circular buffer.
 384  *****************************************************************************/
 385 static void Display( vout_thread_t *p_vout, picture_t *p_pic )
 386 {
 387     int i_index;
 388     mtime_t i_date;
 389
 390     i_index = p_vout->p_sys->i_index;
 391
 392     vlc_memcpy( p_vout->p_sys->p_list[i_index]->p_data, p_pic->p->p_pixels,
 393                 p_vout->p_sys->i_datasize );
 394
 395     i_date = snapshot_GetMovietime( p_vout );
 396
 397     p_vout->p_sys->p_list[i_index]->date = i_date;
 398
 399     i_index++;
 400
 401     if( i_index >= p_vout->p_sys->i_size )
 402     {
 403         i_index = 0;
 404     }
 405
 406     p_vout->p_sys->i_index = i_index;
 407 }
 408