git.sesse.net Git - vlc/blob - src/misc/filter_chain.c

   1 /*****************************************************************************
   2  * filter_chain.c : Handle chains of filter_t objects.
   3  *****************************************************************************
   4  * Copyright (C) 2008 the VideoLAN team
   5  * $Id$
   6  *
   7  * Author: Antoine Cellerier <dionoea at videolan dot org>
   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 #include <vlc_filter.h>
  25 #include <vlc_arrays.h>
  26
  27 struct filter_chain_t
  28 {
  29     vlc_object_t *p_this; /* Parent object */
  30
  31     vlc_array_t filters; /* List of filters */
  32
  33     char *psz_capability; /* Capability of all the filters in the chain */
  34     es_format_t fmt_in; /* Input format (read only) */
  35     es_format_t fmt_out; /* Output format (writable depending on ... */
  36     bool b_allow_fmt_out_change; /* allow changing fmt_out if true */
  37
  38     int (* pf_buffer_allocation_init)( filter_t *, void *p_data ); /* Callback called once filter allocation has succeeded to initialize the filter's buffer allocation callbacks. This function is responsible for setting p_owner if needed. */
  39     void (* pf_buffer_allocation_clear)( filter_t * ); /* Callback called on filter removal from chain to clean up buffer allocation callbacks data (ie p_owner) */
  40     void *p_buffer_allocation_data; /* Data for pf_buffer_allocation_init */
  41 };
  42
  43 /**
  44  * Filter chain initialisation
  45  */
  46 filter_chain_t *__filter_chain_New( vlc_object_t *p_this,
  47                                     const char *psz_capability,
  48                                     bool b_allow_fmt_out_change,
  49                       int (*pf_buffer_allocation_init)( filter_t *, void * ),
  50                       void (*pf_buffer_allocation_clear)( filter_t * ),
  51                       void *p_buffer_allocation_data )
  52 {
  53     filter_chain_t *p_chain = (filter_chain_t *)
  54         malloc( sizeof( filter_chain_t ) );
  55     if( !p_chain ) return NULL;
  56     p_chain->p_this = p_this;
  57     vlc_array_init( &p_chain->filters );
  58     p_chain->psz_capability = strdup( psz_capability );
  59     if( !p_chain->psz_capability )
  60     {
  61         free( p_chain );
  62         return NULL;
  63     }
  64     es_format_Init( &p_chain->fmt_in, UNKNOWN_ES, 0 );
  65     es_format_Init( &p_chain->fmt_out, UNKNOWN_ES, 0 );
  66     p_chain->b_allow_fmt_out_change = b_allow_fmt_out_change;
  67
  68     p_chain->pf_buffer_allocation_init = pf_buffer_allocation_init;
  69     p_chain->pf_buffer_allocation_clear = pf_buffer_allocation_clear;
  70     p_chain->p_buffer_allocation_data = p_buffer_allocation_data;
  71
  72     return p_chain;
  73 }
  74
  75 /**
  76  * Filter chain destruction
  77  */
  78 void filter_chain_Delete( filter_chain_t *p_chain )
  79 {
  80     while( p_chain->filters.i_count )
  81         filter_chain_DeleteFilter( p_chain,
  82                                    (filter_t*)p_chain->filters.pp_elems[0] );
  83     vlc_array_clear( &p_chain->filters );
  84     free( p_chain->psz_capability );
  85     es_format_Clean( &p_chain->fmt_in );
  86     es_format_Clean( &p_chain->fmt_out );
  87     free( p_chain );
  88 }
  89 /**
  90  * Filter chain reinitialisation
  91  */
  92 void filter_chain_Reset( filter_chain_t *p_chain, const es_format_t *p_fmt_in,
  93                          const es_format_t *p_fmt_out )
  94 {
  95     while( p_chain->filters.i_count )
  96         filter_chain_DeleteFilter( p_chain,
  97                                    (filter_t*)p_chain->filters.pp_elems[0] );
  98     es_format_Clean( &p_chain->fmt_in );
  99     es_format_Clean( &p_chain->fmt_out );
 100     es_format_Copy( &p_chain->fmt_in, p_fmt_in );
 101     es_format_Copy( &p_chain->fmt_out, p_fmt_out );
 102 }
 103
 104
 105 /**
 106  * Modifying the filter chain
 107  */
 108 filter_t *filter_chain_AppendFilter( filter_chain_t *p_chain,
 109                                      const char *psz_name,
 110                                      config_chain_t *p_cfg,
 111                                      const es_format_t *p_fmt_in,
 112                                      const es_format_t *p_fmt_out )
 113 {
 114     filter_t *p_filter =
 115         vlc_object_create( p_chain->p_this, VLC_OBJECT_FILTER );
 116     if( !p_filter ) return NULL;
 117     vlc_object_attach( p_filter, p_chain->p_this );
 118
 119     if( !p_fmt_in )
 120     {
 121         if( p_chain->filters.i_count )
 122             p_fmt_in = &((filter_t*)p_chain->filters.pp_elems[p_chain->filters.i_count-1])->fmt_out;
 123         else
 124             p_fmt_in = &p_chain->fmt_in;
 125     }
 126
 127     if( !p_fmt_out )
 128     {
 129         p_fmt_out = &p_chain->fmt_out;
 130     }
 131
 132     es_format_Copy( &p_filter->fmt_in, p_fmt_in );
 133     es_format_Copy( &p_filter->fmt_out, p_fmt_out );
 134     p_filter->p_cfg = p_cfg;
 135     p_filter->b_allow_fmt_out_change = p_chain->b_allow_fmt_out_change;
 136
 137     p_filter->p_module = module_Need( p_filter, p_chain->psz_capability,
 138                                       psz_name, psz_name ? true : false );
 139
 140     if( !p_filter->p_module )
 141         goto error;
 142
 143     if( p_filter->b_allow_fmt_out_change )
 144     {
 145         es_format_Clean( &p_chain->fmt_out );
 146         es_format_Copy( &p_chain->fmt_out, &p_filter->fmt_out );
 147     }
 148
 149     if( p_chain->pf_buffer_allocation_init( p_filter,
 150             p_chain->p_buffer_allocation_data ) != VLC_SUCCESS )
 151         goto error;
 152
 153     vlc_array_append( &p_chain->filters, p_filter );
 154
 155     msg_Dbg( p_chain->p_this, "Filter '%s' (%p) appended to chain",
 156              psz_name, p_filter );
 157
 158     return p_filter;
 159
 160     error:
 161         msg_Err( p_chain->p_this, "Failed to create video filter '%s'",
 162                  psz_name );
 163         if( p_filter->p_module ) module_Unneed( p_filter,
 164                                                 p_filter->p_module );
 165         es_format_Clean( &p_filter->fmt_in );
 166         es_format_Clean( &p_filter->fmt_out );
 167         vlc_object_detach( p_filter );
 168         vlc_object_release( p_filter );
 169         return NULL;
 170 }
 171
 172 int filter_chain_AppendFromString( filter_chain_t *p_chain,
 173                                          const char *psz_string )
 174 {
 175     config_chain_t *p_cfg = NULL;
 176     char *psz_name = NULL;
 177
 178     if( !psz_string || !*psz_string ) return 0;
 179
 180     psz_string = config_ChainCreate( &psz_name, &p_cfg, psz_string );
 181
 182     filter_t *p_filter = filter_chain_AppendFilter( p_chain, psz_name, p_cfg,
 183                                                     NULL, NULL );
 184     if( !p_filter )
 185     {
 186         msg_Err( p_chain->p_this, "Failed while trying to append '%s' "
 187                  "to filter chain", psz_name );
 188         free( psz_name );
 189         free( p_cfg );
 190         return -1;
 191     }
 192     free( psz_name );
 193
 194     int ret = filter_chain_AppendFromString( p_chain, psz_string );
 195     if( ret < 0 )
 196     {
 197         filter_chain_DeleteFilter( p_chain, p_filter );
 198         return ret;
 199     }
 200     return 1 + ret;
 201 }
 202
 203 int filter_chain_DeleteFilter( filter_chain_t *p_chain, filter_t *p_filter )
 204 {
 205     int i;
 206     /* Find the filter in the chain */
 207     for( i = 0; i < p_chain->filters.i_count; i++ )
 208         if( (filter_t*)p_chain->filters.pp_elems[i] == p_filter )
 209             break;
 210
 211     /* Oops, filter wasn't found */
 212     if( i == p_chain->filters.i_count )
 213     {
 214         msg_Err( p_chain->p_this, "Couldn't find filter '%s' (%p) when trying "
 215                  "to remove it from chain", p_filter->psz_object_name,
 216                  p_filter );
 217         return VLC_EGENERIC;
 218     }
 219
 220     /* Remove it from the chain */
 221     vlc_array_remove( &p_chain->filters, i );
 222     msg_Dbg( p_chain->p_this, "Filter '%s' (%p) removed from chain",
 223              p_filter->psz_object_name, p_filter );
 224
 225     /* Destroy the filter object */
 226     if( p_chain->pf_buffer_allocation_clear )
 227         p_chain->pf_buffer_allocation_clear( p_filter );
 228     vlc_object_detach( p_filter );
 229     if( p_filter->p_module )
 230         module_Unneed( p_filter, p_filter->p_module );
 231     vlc_object_release( p_filter );
 232
 233     /* FIXME: check fmt_in/fmt_out consitency */
 234
 235     return VLC_SUCCESS;
 236 }
 237
 238 /**
 239  * Reading from the filter chain
 240  */
 241 filter_t *filter_chain_GetFilter( filter_chain_t *p_chain, int i_position,
 242                                   const char *psz_name )
 243 {
 244     int i;
 245     filter_t **pp_filters = (filter_t **)p_chain->filters.pp_elems;
 246
 247     if( i_position < 0 )
 248         return NULL;
 249
 250     if( !psz_name )
 251     {
 252         if( i_position >= p_chain->filters.i_count )
 253             return NULL;
 254         return pp_filters[i_position];
 255     }
 256
 257     for( i = 0; i < p_chain->filters.i_count; i++ )
 258     {
 259         if( !strcmp( psz_name, pp_filters[i]->psz_object_name ) )
 260             i_position--;
 261         if( i_position < 0 )
 262             return pp_filters[i];
 263    }
 264    return NULL;
 265 }
 266
 267 int filter_chain_GetLength( filter_chain_t *p_chain )
 268 {
 269     return p_chain->filters.i_count;
 270 }
 271
 272 const es_format_t *filter_chain_GetFmtOut( filter_chain_t *p_chain )
 273 {
 274     return &p_chain->fmt_out;
 275 }
 276
 277 /**
 278  * Apply the filter chain
 279  */
 280 picture_t *filter_chain_VideoFilter( filter_chain_t *p_chain, picture_t *p_pic )
 281 {
 282     int i;
 283     filter_t **pp_filter = (filter_t **)p_chain->filters.pp_elems;
 284     for( i = 0; i < p_chain->filters.i_count; i++ )
 285     {
 286         filter_t *p_filter = pp_filter[i];
 287         p_pic = p_filter->pf_video_filter( p_filter, p_pic );
 288         if( !p_pic )
 289             return NULL;
 290     }
 291     return p_pic;
 292 }
 293
 294 block_t *filter_chain_AudioFilter( filter_chain_t *p_chain, block_t *p_block )
 295 {
 296     int i;
 297     filter_t **pp_filter = (filter_t **)p_chain->filters.pp_elems;
 298     for( i = 0; i < p_chain->filters.i_count; i++ )
 299     {
 300         filter_t *p_filter = pp_filter[i];
 301         p_block = p_filter->pf_audio_filter( p_filter, p_block );
 302         if( !p_block )
 303             return NULL;
 304     }
 305     return p_block;
 306 }
 307
 308 void filter_chain_SubFilter( filter_chain_t *p_chain,
 309                              mtime_t display_date )
 310 {
 311     int i;
 312     filter_t **pp_filter = (filter_t **)p_chain->filters.pp_elems;
 313     for( i = 0; i < p_chain->filters.i_count; i++ )
 314     {
 315         filter_t *p_filter = pp_filter[i];
 316         subpicture_t *p_subpic = p_filter->pf_sub_filter( p_filter, display_date );
 317         if( p_subpic )
 318             spu_DisplaySubpicture( (spu_t*)p_chain->p_this, p_subpic );
 319     }
 320 }