include/vlc_filter.h

   1 /*****************************************************************************
   2  * vlc_filter.h: filter related structures and functions
   3  *****************************************************************************
   4  * Copyright (C) 1999-2014 VLC authors and VideoLAN
   5  *
   6  * Authors: Gildas Bazin <gbazin@videolan.org>
   7  *          Antoine Cellerier <dionoea at videolan dot org>
   8  *          Rémi Denis-Courmont
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 #ifndef VLC_FILTER_H
  26 #define VLC_FILTER_H 1
  27
  28 #include <vlc_es.h>
  29
  30 /**
  31  * \defgroup filter Filters
  32  * \ingroup output
  33  * Audio, video, text filters
  34  * @{
  35  * \file
  36  * Filter modules interface
  37  */
  38
  39 typedef struct filter_owner_sys_t filter_owner_sys_t;
  40
  41 typedef struct filter_owner_t
  42 {
  43     void *sys;
  44
  45     union
  46     {
  47         struct
  48         {
  49             picture_t * (*buffer_new)( filter_t * );
  50         } video;
  51         struct
  52         {
  53             subpicture_t * (*buffer_new)( filter_t * );
  54         } sub;
  55     };
  56 } filter_owner_t;
  57
  58 struct vlc_mouse_t;
  59
  60 /** Structure describing a filter
  61  * @warning BIG FAT WARNING : the code relies on the first 4 members of
  62  * filter_t and decoder_t to be the same, so if you have anything to add,
  63  * do it at the end of the structure.
  64  */
  65 struct filter_t
  66 {
  67     VLC_COMMON_MEMBERS
  68
  69     /* Module properties */
  70     module_t *          p_module;
  71     filter_sys_t *      p_sys;
  72
  73     /* Input format */
  74     es_format_t         fmt_in;
  75
  76     /* Output format of filter */
  77     es_format_t         fmt_out;
  78     bool                b_allow_fmt_out_change;
  79
  80     /* Filter configuration */
  81     config_chain_t *    p_cfg;
  82
  83     union
  84     {
  85         /** Filter a picture (video filter) */
  86         picture_t * (*pf_video_filter)( filter_t *, picture_t * );
  87
  88         /** Filter an audio block (audio filter) */
  89         block_t * (*pf_audio_filter)( filter_t *, block_t * );
  90
  91         /** Blend a subpicture onto a picture (blend) */
  92         void (*pf_video_blend)( filter_t *,  picture_t *, const picture_t *,
  93                                  int, int, int );
  94
  95         /** Generate a subpicture (sub source) */
  96         subpicture_t *(*pf_sub_source)( filter_t *, mtime_t );
  97
  98         /** Filter a subpicture (sub filter) */
  99         subpicture_t *(*pf_sub_filter)( filter_t *, subpicture_t * );
 100
 101         /** Render text (text render) */
 102         int (*pf_render)( filter_t *, subpicture_region_t *,
 103                           subpicture_region_t *, const vlc_fourcc_t * );
 104     };
 105
 106     union
 107     {
 108         /* TODO: video filter drain */
 109         /** Drain (audio filter) */
 110         block_t *(*pf_audio_drain) ( filter_t * );
 111     };
 112
 113     /** Flush
 114      *
 115      * Flush (i.e. discard) any internal buffer in a video or audio filter.
 116      */
 117     void (*pf_flush)( filter_t * );
 118
 119     union
 120     {
 121         /** Filter mouse state (video filter).
 122          *
 123          * If non-NULL, you must convert from output to input formats:
 124          * - If VLC_SUCCESS is returned, the mouse state is propagated.
 125          * - Otherwise, the mouse change is not propagated.
 126          * If NULL, the mouse state is considered unchanged and will be
 127          * propagated. */
 128         int (*pf_video_mouse)( filter_t *, struct vlc_mouse_t *,
 129                                const struct vlc_mouse_t *p_old,
 130                                const struct vlc_mouse_t *p_new );
 131         int (*pf_sub_mouse)( filter_t *, const struct vlc_mouse_t *p_old,
 132                              const struct vlc_mouse_t *p_new,
 133                              const video_format_t * );
 134     };
 135
 136     /* Input attachments
 137      * XXX use filter_GetInputAttachments */
 138     int (*pf_get_attachments)( filter_t *, input_attachment_t ***, int * );
 139
 140     /* Private structure for the owner of the decoder */
 141     filter_owner_t      owner;
 142 };
 143
 144 /**
 145  * This function will return a new picture usable by p_filter as an output
 146  * buffer. You have to release it using picture_Release or by returning
 147  * it to the caller as a pf_video_filter return value.
 148  * Provided for convenience.
 149  *
 150  * \param p_filter filter_t object
 151  * \return new picture on success or NULL on failure
 152  */
 153 static inline picture_t *filter_NewPicture( filter_t *p_filter )
 154 {
 155     picture_t *pic = p_filter->owner.video.buffer_new( p_filter );
 156     if( pic == NULL )
 157         msg_Warn( p_filter, "can't get output picture" );
 158     return pic;
 159 }
 160
 161 /**
 162  * Flush a filter
 163  *
 164  * This function will flush the state of a filter (audio or video).
 165  */
 166 static inline void filter_Flush( filter_t *p_filter )
 167 {
 168     if( p_filter->pf_flush != NULL )
 169         p_filter->pf_flush( p_filter );
 170 }
 171
 172 /**
 173  * This function will drain, then flush an audio filter.
 174  */
 175 static inline block_t *filter_DrainAudio( filter_t *p_filter )
 176 {
 177     if( p_filter->pf_audio_drain )
 178         return p_filter->pf_audio_drain( p_filter );
 179     else
 180         return NULL;
 181 }
 182
 183 /**
 184  * This function will return a new subpicture usable by p_filter as an output
 185  * buffer. You have to release it using subpicture_Delete or by returning it to
 186  * the caller as a pf_sub_source return value.
 187  * Provided for convenience.
 188  *
 189  * \param p_filter filter_t object
 190  * \return new subpicture
 191  */
 192 static inline subpicture_t *filter_NewSubpicture( filter_t *p_filter )
 193 {
 194     subpicture_t *subpic = p_filter->owner.sub.buffer_new( p_filter );
 195     if( subpic == NULL )
 196         msg_Warn( p_filter, "can't get output subpicture" );
 197     return subpic;
 198 }
 199
 200 /**
 201  * This function gives all input attachments at once.
 202  *
 203  * You MUST release the returned values
 204  */
 205 static inline int filter_GetInputAttachments( filter_t *p_filter,
 206                                               input_attachment_t ***ppp_attachment,
 207                                               int *pi_attachment )
 208 {
 209     if( !p_filter->pf_get_attachments )
 210         return VLC_EGENERIC;
 211     return p_filter->pf_get_attachments( p_filter,
 212                                          ppp_attachment, pi_attachment );
 213 }
 214
 215 /**
 216  * It creates a blend filter.
 217  *
 218  * Only the chroma properties of the dest format is used (chroma
 219  * type, rgb masks and shifts)
 220  */
 221 VLC_API filter_t * filter_NewBlend( vlc_object_t *, const video_format_t *p_dst_chroma ) VLC_USED;
 222
 223 /**
 224  * It configures blend filter parameters that are allowed to changed
 225  * after the creation.
 226  */
 227 VLC_API int filter_ConfigureBlend( filter_t *, int i_dst_width, int i_dst_height, const video_format_t *p_src );
 228
 229 /**
 230  * It blends a picture into another one.
 231  *
 232  * The input picture is not modified and not released.
 233  */
 234 VLC_API int filter_Blend( filter_t *, picture_t *p_dst, int i_dst_x, int i_dst_y, const picture_t *p_src, int i_alpha );
 235
 236 /**
 237  * It destroys a blend filter created by filter_NewBlend.
 238  */
 239 VLC_API void filter_DeleteBlend( filter_t * );
 240
 241 /**
 242  * Create a picture_t *(*)( filter_t *, picture_t * ) compatible wrapper
 243  * using a void (*)( filter_t *, picture_t *, picture_t * ) function
 244  *
 245  * Currently used by the chroma video filters
 246  */
 247 #define VIDEO_FILTER_WRAPPER( name )                                    \
 248     static picture_t *name ## _Filter ( filter_t *p_filter,             \
 249                                         picture_t *p_pic )              \
 250     {                                                                   \
 251         picture_t *p_outpic = filter_NewPicture( p_filter );            \
 252         if( p_outpic )                                                  \
 253         {                                                               \
 254             name( p_filter, p_pic, p_outpic );                          \
 255             picture_CopyProperties( p_outpic, p_pic );                  \
 256         }                                                               \
 257         picture_Release( p_pic );                                       \
 258         return p_outpic;                                                \
 259     }
 260
 261 /**
 262  * Filter chain management API
 263  * The filter chain management API is used to dynamically construct filters
 264  * and add them in a chain.
 265  */
 266
 267 typedef struct filter_chain_t filter_chain_t;
 268
 269 /**
 270  * Create new filter chain
 271  *
 272  * \param p_object pointer to a vlc object
 273  * \param psz_capability vlc capability of filters in filter chain
 274  * \return pointer to a filter chain
 275  */
 276 filter_chain_t * filter_chain_New( vlc_object_t *, const char * )
 277 VLC_USED;
 278 #define filter_chain_New( a, b ) filter_chain_New( VLC_OBJECT( a ), b )
 279
 280 /**
 281  * Creates a new video filter chain.
 282  *
 283  * \param obj pointer to parent VLC object
 284  * \param change whether to allow changing the output format
 285  * \param owner owner video buffer callbacks
 286  * \return new filter chain, or NULL on error
 287  */
 288 VLC_API filter_chain_t * filter_chain_NewVideo( vlc_object_t *obj, bool change,
 289                                                 const filter_owner_t *owner )
 290 VLC_USED;
 291 #define filter_chain_NewVideo( a, b, c ) \
 292         filter_chain_NewVideo( VLC_OBJECT( a ), b, c )
 293
 294 /**
 295  * Delete filter chain will delete all filters in the chain and free all
 296  * allocated data. The pointer to the filter chain is then no longer valid.
 297  *
 298  * \param p_chain pointer to filter chain
 299  */
 300 VLC_API void filter_chain_Delete( filter_chain_t * );
 301
 302 /**
 303  * Reset filter chain will delete all filters in the chain and
 304  * reset p_fmt_in and p_fmt_out to the new values.
 305  *
 306  * \param p_chain pointer to filter chain
 307  * \param p_fmt_in new fmt_in params
 308  * \param p_fmt_out new fmt_out params
 309  */
 310 VLC_API void filter_chain_Reset( filter_chain_t *, const es_format_t *, const es_format_t * );
 311
 312 /**
 313  * Append a filter to the chain.
 314  *
 315  * \param chain filter chain to append a filter to
 316  * \param name filter name
 317  * \param fmt_in filter input format
 318  * \param fmt_out filter output format
 319  * \return a pointer to the filter or NULL on error
 320  */
 321 VLC_API filter_t *filter_chain_AppendFilter(filter_chain_t *chain,
 322     const char *name, config_chain_t *cfg, const es_format_t *fmt_in,
 323     const es_format_t *fmt_out);
 324
 325 /**
 326  * Append a conversion to the chain.
 327  *
 328  * \param chain filter chain to append a filter to
 329  * \param fmt_in filter input format
 330  * \param fmt_out filter output format
 331  * \retval 0 on success
 332  * \retval -1 on failure
 333  */
 334 VLC_API int filter_chain_AppendConverter(filter_chain_t *chain,
 335     const es_format_t *fmt_in, const es_format_t *fmt_out);
 336
 337 /**
 338  * Append new filter to filter chain from string.
 339  *
 340  * \param chain filter chain to append a filter to
 341  * \param str filters chain nul-terminated string
 342  */
 343 VLC_API int filter_chain_AppendFromString(filter_chain_t *chain,
 344                                           const char *str);
 345
 346 /**
 347  * Delete filter from filter chain. This function also releases the filter
 348  * object and unloads the filter modules. The pointer to p_filter is no
 349  * longer valid after this function successfully returns.
 350  *
 351  * \param chain filter chain to remove the filter from
 352  * \param filter filter to remove from the chain and delete
 353  */
 354 VLC_API void filter_chain_DeleteFilter(filter_chain_t *chain,
 355                                        filter_t *filter);
 356
 357 /**
 358  * Get the number of filters in the filter chain.
 359  *
 360  * \param chain pointer to filter chain
 361  * \return number of filters in this filter chain
 362  */
 363 VLC_API int filter_chain_GetLength(filter_chain_t *chain);
 364
 365 /**
 366  * Get last output format of the last element in the filter chain.
 367  *
 368  * \param chain filter chain
 369  */
 370 VLC_API const es_format_t *filter_chain_GetFmtOut(filter_chain_t *chain);
 371
 372 /**
 373  * Apply the filter chain to a video picture.
 374  *
 375  * \param chain pointer to filter chain
 376  * \param pic picture to apply filters to
 377  * \return modified picture after applying all video filters
 378  */
 379 VLC_API picture_t *filter_chain_VideoFilter(filter_chain_t *chain,
 380                                             picture_t *pic);
 381
 382 /**
 383  * Flush a video filter chain.
 384  */
 385 VLC_API void filter_chain_VideoFlush( filter_chain_t * );
 386
 387 /**
 388  * Generate subpictures from a chain of subpicture source "filters".
 389  *
 390  * \param chain filter chain
 391  * \param display_date of subpictures
 392  */
 393 void filter_chain_SubSource(filter_chain_t *chain, spu_t *,
 394                             mtime_t display_date);
 395
 396 /**
 397  * Apply filter chain to subpictures.
 398  *
 399  * \param chain filter chain
 400  * \param subpic subpicture to apply filters on
 401  * \return modified subpicture after applying all subpicture filters
 402  */
 403 VLC_API subpicture_t *filter_chain_SubFilter(filter_chain_t *chain,
 404                                              subpicture_t *subpic);
 405
 406 /**
 407  * Apply the filter chain to a mouse state.
 408  *
 409  * It will be applied from the output to the input. It makes sense only
 410  * for a video filter chain.
 411  *
 412  * The vlc_mouse_t* pointers may be the same.
 413  */
 414 VLC_API int filter_chain_MouseFilter( filter_chain_t *, struct vlc_mouse_t *,
 415                                       const struct vlc_mouse_t * );
 416
 417 /**
 418  * Inform the filter chain of mouse state.
 419  *
 420  * It makes sense only for a sub source chain.
 421  */
 422 VLC_API int filter_chain_MouseEvent( filter_chain_t *,
 423                                      const struct vlc_mouse_t *,
 424                                      const video_format_t * );
 425
 426 int filter_chain_ForEach( filter_chain_t *chain,
 427                           int (*cb)( filter_t *, void * ), void *opaque );
 428
 429 /** @} */
 430 #endif /* _VLC_FILTER_H */