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  *   vout-snapshot-list-pointer : the pointer on the first element in the list
  30  *   vout-snapshot-datasize     : size of a snapshot
  31  *                           (also available in snapshot_t->i_datasize)
  32  *   vout-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( "vout-snapshot-width", 320, NULL, WIDTH_TEXT, WIDTH_LONGTEXT, false )
  88     add_integer( "vout-snapshot-height", 200, NULL, HEIGHT_TEXT, HEIGHT_LONGTEXT, false )
  89     add_string( "vout-snapshot-chroma", "RV32", NULL, CHROMA_TEXT, CHROMA_LONGTEXT, true )
  90         add_deprecated_alias( "snapshot-chroma" )
  91     add_integer( "vout-snapshot-cache-size", 50, NULL, CACHE_TEXT, CACHE_LONGTEXT, true )
  92         add_deprecated_alias( "snapshot-cache-size" )
  93
  94     set_callbacks( Create, Destroy )
  95 vlc_module_end ()
  96
  97 /*****************************************************************************
  98  * vout_sys_t: video output descriptor
  99  *****************************************************************************/
 100 typedef struct snapshot_t
 101 {
 102   uint8_t *p_data;   /* Data area */
 103
 104   int i_width;       /* In pixels */
 105   int i_height;      /* In pixels */
 106   int i_datasize;    /* In bytes */
 107   mtime_t date;      /* Presentation time */
 108 } snapshot_t;
 109
 110 struct vout_sys_t
 111 {
 112     snapshot_t **p_list;    /* List of available snapshots */
 113     int i_index;            /* Index of the next available list member */
 114     int i_size;             /* Size of the cache */
 115     int i_datasize;         /* Size of an image */
 116     input_thread_t *p_input;             /* The input thread */
 117 };
 118
 119 /*****************************************************************************
 120  * Create: allocates video thread
 121  *****************************************************************************
 122  * This function allocates and initializes a vout method.
 123  *****************************************************************************/
 124 static int Create( vlc_object_t *p_this )
 125 {
 126     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 127
 128     /* Allocate instance and initialize some members */
 129     p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
 130     if( ! p_vout->p_sys )
 131         return VLC_ENOMEM;
 132
 133     var_Create( p_vout, "vout-snapshot-width", VLC_VAR_INTEGER );
 134     var_Create( p_vout, "vout-snapshot-height", VLC_VAR_INTEGER );
 135     var_Create( p_vout, "vout-snapshot-datasize", VLC_VAR_INTEGER );
 136     var_Create( p_vout, "vout-snapshot-cache-size", VLC_VAR_INTEGER );
 137     var_Create( p_vout, "vout-snapshot-list-pointer", VLC_VAR_ADDRESS );
 138
 139     p_vout->pf_init = Init;
 140     p_vout->pf_end = End;
 141     p_vout->pf_manage = NULL;
 142     p_vout->pf_render = NULL;
 143     p_vout->pf_display = Display;
 144
 145     return VLC_SUCCESS;
 146 }
 147
 148 /*****************************************************************************
 149  * Init: initialize video thread
 150  *****************************************************************************/
 151 static int Init( vout_thread_t *p_vout )
 152 {
 153     int i_index;
 154     picture_t *p_pic;
 155     vlc_value_t val;
 156     char* psz_chroma;
 157     int i_chroma;
 158     int i_width;
 159     int i_height;
 160     int i_datasize;
 161
 162     i_width  = config_GetInt( p_vout, "vout-snapshot-width" );
 163     i_height = config_GetInt( p_vout, "vout-snapshot-height" );
 164
 165     psz_chroma = config_GetPsz( p_vout, "vout-snapshot-chroma" );
 166     if( psz_chroma )
 167     {
 168         if( strlen( psz_chroma ) < 4 )
 169         {
 170             msg_Err( p_vout, "vout-snapshot-chroma should be 4 characters long" );
 171             return VLC_EGENERIC;
 172         }
 173         i_chroma = VLC_FOURCC( psz_chroma[0], psz_chroma[1],
 174                                psz_chroma[2], psz_chroma[3] );
 175         free( psz_chroma );
 176     }
 177     else
 178     {
 179         msg_Err( p_vout, "Cannot find chroma information." );
 180         return VLC_EGENERIC;
 181     }
 182
 183     I_OUTPUTPICTURES = 0;
 184
 185     /* Initialize the output structure */
 186     p_vout->output.i_chroma = i_chroma;
 187     p_vout->output.pf_setpalette = NULL;
 188     p_vout->output.i_width = i_width;
 189     p_vout->output.i_height = i_height;
 190     p_vout->output.i_aspect = p_vout->output.i_width
 191                                * VOUT_ASPECT_FACTOR / p_vout->output.i_height;
 192
 193
 194     /* Define the bitmasks */
 195     switch( i_chroma )
 196     {
 197       case VLC_FOURCC( 'R','V','1','5' ):
 198         p_vout->output.i_rmask = 0x001f;
 199         p_vout->output.i_gmask = 0x03e0;
 200         p_vout->output.i_bmask = 0x7c00;
 201         break;
 202
 203       case VLC_FOURCC( 'R','V','1','6' ):
 204         p_vout->output.i_rmask = 0x001f;
 205         p_vout->output.i_gmask = 0x07e0;
 206         p_vout->output.i_bmask = 0xf800;
 207         break;
 208
 209       case VLC_FOURCC( 'R','V','2','4' ):
 210         p_vout->output.i_rmask = 0xff0000;
 211         p_vout->output.i_gmask = 0x00ff00;
 212         p_vout->output.i_bmask = 0x0000ff;
 213         break;
 214
 215       case VLC_FOURCC( 'R','V','3','2' ):
 216         p_vout->output.i_rmask = 0xff0000;
 217         p_vout->output.i_gmask = 0x00ff00;
 218         p_vout->output.i_bmask = 0x0000ff;
 219         break;
 220     }
 221
 222     /* Try to initialize 1 direct buffer */
 223     p_pic = NULL;
 224
 225     /* Find an empty picture slot */
 226     for( i_index = 0 ; i_index < VOUT_MAX_PICTURES ; i_index++ )
 227     {
 228         if( p_vout->p_picture[ i_index ].i_status == FREE_PICTURE )
 229         {
 230             p_pic = p_vout->p_picture + i_index;
 231             break;
 232         }
 233     }
 234
 235     /* Allocate the picture */
 236     if( p_pic == NULL )
 237     {
 238         return VLC_SUCCESS;
 239     }
 240
 241     vout_AllocatePicture( VLC_OBJECT(p_vout), p_pic, p_vout->output.i_chroma,
 242                           p_vout->output.i_width, p_vout->output.i_height,
 243                           p_vout->output.i_aspect );
 244
 245     if( p_pic->i_planes == 0 )
 246     {
 247         return VLC_EGENERIC;
 248     }
 249
 250     p_pic->i_status = DESTROYED_PICTURE;
 251     p_pic->i_type   = DIRECT_PICTURE;
 252
 253     PP_OUTPUTPICTURE[ I_OUTPUTPICTURES ] = p_pic;
 254
 255     I_OUTPUTPICTURES++;
 256
 257
 258     /* Get datasize and set variables */
 259     i_datasize = i_width * i_height * p_pic->p->i_pixel_pitch;
 260
 261     p_vout->p_sys->i_datasize = i_datasize;
 262     p_vout->p_sys->i_index = 0;
 263     p_vout->p_sys->i_size = config_GetInt( p_vout, "vout-snapshot-cache-size" );
 264
 265     if( p_vout->p_sys->i_size < 2 )
 266     {
 267         msg_Err( p_vout, "vout-snapshot-cache-size must be at least 1." );
 268         return VLC_EGENERIC;
 269     }
 270
 271     p_vout->p_sys->p_list = malloc( p_vout->p_sys->i_size * sizeof( snapshot_t * ) );
 272
 273     if( p_vout->p_sys->p_list == NULL )
 274         return VLC_ENOMEM;
 275
 276     /* Initialize the structures for the circular buffer */
 277     for( i_index = 0; i_index < p_vout->p_sys->i_size; i_index++ )
 278     {
 279         snapshot_t *p_snapshot = malloc( sizeof( snapshot_t ) );
 280
 281         if( p_snapshot == NULL )
 282             return VLC_ENOMEM;
 283
 284         p_snapshot->i_width = i_width;
 285         p_snapshot->i_height = i_height;
 286         p_snapshot->i_datasize = i_datasize;
 287         p_snapshot->date = 0;
 288         p_snapshot->p_data = malloc( i_datasize );
 289         if( p_snapshot->p_data == NULL )
 290         {
 291             free( p_snapshot );
 292             return VLC_ENOMEM;
 293         }
 294         p_vout->p_sys->p_list[i_index] = p_snapshot;
 295     }
 296
 297     val.i_int = i_width;
 298     var_Set( p_vout, "vout-snapshot-width", val );
 299     val.i_int = i_height;
 300     var_Set( p_vout, "vout-snapshot-height", val );
 301     val.i_int = i_datasize;
 302     var_Set( p_vout, "vout-snapshot-datasize", val );
 303
 304     val.i_int = p_vout->p_sys->i_size;
 305     var_Set( p_vout, "vout-snapshot-cache-size", val );
 306
 307     val.p_address = p_vout->p_sys->p_list;
 308     var_Set( p_vout, "vout-snapshot-list-pointer", val );
 309
 310     /* Get the p_input pointer (to access video times) */
 311     p_vout->p_sys->p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT,
 312                                               FIND_PARENT );
 313
 314     if( !p_vout->p_sys->p_input )
 315         return VLC_ENOOBJ;
 316
 317     if( var_Create( p_vout->p_sys->p_input, "vout-snapshot-id", VLC_VAR_INTEGER ) )
 318     {
 319         msg_Err( p_vout, "Cannot create vout-snapshot-id variable in p_input(%p).",
 320                  p_vout->p_sys->p_input );
 321         return VLC_EGENERIC;
 322     }
 323
 324     /* Register the snapshot vout module at the input level */
 325     val.p_address = p_vout;
 326
 327     if( var_Set( p_vout->p_sys->p_input, "vout-snapshot-id", val ) )
 328     {
 329         msg_Err( p_vout, "Cannot register vout-snapshot-id in p_input(%p).",
 330                  p_vout->p_sys->p_input );
 331         return VLC_EGENERIC;
 332     }
 333
 334     return VLC_SUCCESS;
 335 }
 336
 337 /*****************************************************************************
 338  * End: terminate video thread output method
 339  *****************************************************************************/
 340 static void End( vout_thread_t *p_vout )
 341 {
 342     (void)p_vout;
 343 }
 344
 345 /*****************************************************************************
 346  * Destroy: destroy video thread
 347  *****************************************************************************
 348  * Terminate an output method created by Create
 349  *****************************************************************************/
 350 static void Destroy( vlc_object_t *p_this )
 351 {
 352     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
 353     int i_index;
 354
 355     var_Destroy( p_vout->p_sys->p_input, "vout-snapshot-id" );
 356
 357     vlc_object_release( p_vout->p_sys->p_input );
 358     var_Destroy( p_this, "vout-snapshot-width" );
 359     var_Destroy( p_this, "vout-snapshot-height" );
 360     var_Destroy( p_this, "vout-snapshot-datasize" );
 361
 362     for( i_index = 0 ; i_index < p_vout->p_sys->i_size ; i_index++ )
 363     {
 364         free( p_vout->p_sys->p_list[ i_index ]->p_data );
 365     }
 366     free( p_vout->p_sys->p_list );
 367     /* Destroy structure */
 368     free( p_vout->p_sys );
 369 }
 370
 371 /* Return the position in ms from the start of the movie */
 372 static mtime_t snapshot_GetMovietime( vout_thread_t *p_vout )
 373 {
 374     input_thread_t *p_input = p_vout->p_sys->p_input;
 375     if( !p_input )
 376         return 0;
 377
 378     return var_GetTime( p_input, "time" ) / 1000;
 379 }
 380
 381 /*****************************************************************************
 382  * Display: displays previously rendered output
 383  *****************************************************************************
 384  * This function copies the rendered picture into our circular buffer.
 385  *****************************************************************************/
 386 static void Display( vout_thread_t *p_vout, picture_t *p_pic )
 387 {
 388     int i_index;
 389     mtime_t i_date;
 390
 391     i_index = p_vout->p_sys->i_index;
 392
 393     vlc_memcpy( p_vout->p_sys->p_list[i_index]->p_data, p_pic->p->p_pixels,
 394                 p_vout->p_sys->i_datasize );
 395
 396     i_date = snapshot_GetMovietime( p_vout );
 397
 398     p_vout->p_sys->p_list[i_index]->date = i_date;
 399
 400     i_index++;
 401
 402     if( i_index >= p_vout->p_sys->i_size )
 403     {
 404         i_index = 0;
 405     }
 406
 407     p_vout->p_sys->i_index = i_index;
 408 }
 409