1 /*****************************************************************************
2 * vlc_codec.h: Definition of the decoder and encoder structures
3 *****************************************************************************
4 * Copyright (C) 1999-2003 VLC authors and VideoLAN
7 * Authors: Gildas Bazin <gbazin@netcourrier.com>
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License as published by
11 * the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
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 Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this program; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
29 #include <vlc_block.h>
31 #include <vlc_picture.h>
32 #include <vlc_subpicture.h>
35 * \defgroup codec Codec
36 * Decoders and encoders
39 * Decoder and encoder modules interface
41 * \defgroup decoder Decoder
42 * Audio, video and text decoders
46 typedef struct decoder_owner_sys_t decoder_owner_sys_t
;
49 * BIG FAT WARNING : the code relies in the first 4 members of filter_t
50 * and decoder_t to be the same, so if you have anything to add, do it
51 * at the end of the structure.
57 /* Module properties */
59 decoder_sys_t
* p_sys
;
61 /* Input format ie from demuxer (XXX: a lot of field could be invalid) */
64 /* Output format of decoder/packetizer */
67 /* Tell the decoder if it is allowed to drop frames */
68 bool b_frame_drop_allowed
;
70 # define VLCDEC_SUCCESS VLC_SUCCESS
71 # define VLCDEC_ECRITICAL VLC_EGENERIC
72 # define VLCDEC_RELOAD (-100)
73 /* This function is called to decode one packetized block.
75 * The module implementation will own the input block (p_block) and should
76 * process and release it. Depending of the decoder type, the module should
77 * send output frames/blocks via decoder_QueueVideo(), decoder_QueueAudio()
78 * or decoder_QueueSub().
80 * If p_block is NULL, the decoder asks the module to drain itself. The
81 * module should return all available output frames/block via the queue
84 * Return values can be:
85 * VLCDEC_SUCCESS: pf_decode will be called again
86 * VLCDEC_ECRITICAL: in case of critical error, pf_decode won't be called
88 * VLCDEC_RELOAD: Request that the decoder should be reloaded. The current
89 * module will be unloaded. Reloading a module may cause a loss of frames.
90 * When returning this status, the implementation shouldn't release or
91 * modify the p_block in argument (The same p_block will be feed to the
92 * next decoder module).
94 int ( * pf_decode
) ( decoder_t
*, block_t
*p_block
);
96 /* This function is called in a loop with the same pp_block argument until
97 * it returns NULL. This allows a module implementation to return more than
98 * one output blocks for one input block.
100 * pp_block or *pp_block can be NULL.
102 * If pp_block and *pp_block are not NULL, the module implementation will
103 * own the input block (*pp_block) and should process and release it. The
104 * module can also process a part of the block. In that case, it should
105 * modify (*pp_block)->p_buffer/i_buffer accordingly and return a valid
106 * output block. The module can also set *pp_block to NULL when the input
109 * If pp_block is not NULL but *pp_block is NULL, a previous call of the pf
110 * function has set the *pp_block to NULL. Here, the module can return new
111 * output block for the same, already processed, input block (the
112 * pf_packetize function will be called as long as the module return an
115 * When the pf function returns NULL, the next call to this function will
116 * have a new a valid pp_block (if the packetizer is not drained).
118 * If pp_block is NULL, the packetizer asks the module to drain itself. In
119 * that case, the module has to return all output frames available (the
120 * pf_packetize function will be called as long as the module return an
123 block_t
* ( * pf_packetize
)( decoder_t
*, block_t
**pp_block
);
125 void ( * pf_flush
) ( decoder_t
* );
127 /* Closed Caption (CEA 608/708) extraction.
128 * If set, it *may* be called after pf_packetize returned data. It should
129 * return CC for the pictures returned by the last pf_packetize call only,
130 * pb_present will be used to known which cc channel are present (but
131 * globaly, not necessary for the current packet. Video decoders should use
132 * the decoder_QueueCc() function to pass closed captions. */
133 block_t
* ( * pf_get_cc
) ( decoder_t
*, bool pb_present
[4], int * );
135 /* Meta data at codec level
136 * The decoder owner set it back to NULL once it has retreived what it needs.
137 * The decoder owner is responsible of its release except when you overwrite it.
139 vlc_meta_t
*p_description
;
143 * XXX You MUST not use them directly.
146 /* Video output callbacks
147 * XXX use decoder_NewPicture */
148 int (*pf_vout_format_update
)( decoder_t
* );
149 picture_t
*(*pf_vout_buffer_new
)( decoder_t
* );
152 * Number of extra (ie in addition to the DPB) picture buffers
153 * needed for decoding.
155 int i_extra_picture_buffers
;
157 /* Audio output callbacks */
158 int (*pf_aout_format_update
)( decoder_t
* );
160 /* SPU output callbacks
161 * XXX use decoder_NewSubpicture */
162 subpicture_t
*(*pf_spu_buffer_new
)( decoder_t
*, const subpicture_updater_t
* );
165 * XXX use decoder_GetInputAttachments */
166 int (*pf_get_attachments
)( decoder_t
*p_dec
, input_attachment_t
***ppp_attachment
, int *pi_attachment
);
169 * XXX use decoder_GetDisplayDate */
170 mtime_t (*pf_get_display_date
)( decoder_t
*, mtime_t
);
173 * XXX use decoder_GetDisplayRate */
174 int (*pf_get_display_rate
)( decoder_t
* );
176 /* XXX use decoder_QueueVideo or decoder_QueueVideoWithCc */
177 int (*pf_queue_video
)( decoder_t
*, picture_t
* );
178 /* XXX use decoder_QueueAudio */
179 int (*pf_queue_audio
)( decoder_t
*, block_t
* );
180 /* XXX use decoder_QueueCC */
181 int (*pf_queue_cc
)( decoder_t
*, block_t
*, bool p_cc_present
[4], int );
182 /* XXX use decoder_QueueSub */
183 int (*pf_queue_sub
)( decoder_t
*, subpicture_t
*);
186 /* Private structure for the owner of the decoder */
187 decoder_owner_sys_t
*p_owner
;
195 * \defgroup encoder Encoder
196 * Audio, video and text encoders
204 /* Module properties */
206 encoder_sys_t
* p_sys
;
208 /* Properties of the input data fed to the encoder */
211 /* Properties of the output of the encoder */
214 block_t
* ( * pf_encode_video
)( encoder_t
*, picture_t
* );
215 block_t
* ( * pf_encode_audio
)( encoder_t
*, block_t
* );
216 block_t
* ( * pf_encode_sub
)( encoder_t
*, subpicture_t
* );
218 /* Common encoder options */
219 int i_threads
; /* Number of threads to use during encoding */
220 int i_iframes
; /* One I frame per i_iframes */
221 int i_bframes
; /* One B frame per i_bframes */
222 int i_tolerance
; /* Bitrate tolerance */
225 config_chain_t
*p_cfg
;
236 * Updates the video output format.
238 * This function notifies the video output pipeline of a new video output
239 * format (fmt_out.video). If there was no video output from the decoder so far
240 * or if the video output format has changed, a new video output will be set
241 * up. decoder_NewPicture() can then be used to allocate picture buffers.
243 * If the format is unchanged, this function has no effects and returns zero.
246 * This function is not reentrant.
248 * @return 0 if the video output was set up successfully, -1 otherwise.
250 static inline int decoder_UpdateVideoFormat( decoder_t
*dec
)
252 assert( dec
->fmt_in
.i_cat
== VIDEO_ES
);
253 if( dec
->fmt_in
.i_cat
== VIDEO_ES
&& dec
->pf_vout_format_update
!= NULL
)
254 return dec
->pf_vout_format_update( dec
);
260 * Allocates an output picture buffer.
262 * This function pulls an output picture buffer for the decoder from the
263 * buffer pool of the video output. The picture must be released with
264 * picture_Release() when it is no longer referenced by the decoder.
267 * This function is reentrant. However, decoder_UpdateVideoFormat() cannot be
268 * used concurrently; the caller is responsible for serialization.
271 * The behaviour is undefined if decoder_UpdateVideoFormat() was not called or
272 * if the last call returned an error.
274 * \return a picture buffer on success, NULL on error
277 static inline picture_t
*decoder_NewPicture( decoder_t
*dec
)
279 return dec
->pf_vout_buffer_new( dec
);
283 * Abort any calls of decoder_NewPicture
285 * If b_abort is true, all pending and futures calls of decoder_NewPicture
286 * will be aborted. This function can be used by asynchronous video decoders
287 * to unblock a thread that is waiting for a picture.
289 VLC_API
void decoder_AbortPictures( decoder_t
*dec
, bool b_abort
);
292 * This function queues a single picture to the video output.
295 * The caller doesn't own the picture anymore after this call (even in case of
297 * FIXME: input_DecoderFrameNext won't work if a module use this function.
299 * \return 0 if the picture is queued, -1 on error
301 static inline int decoder_QueueVideo( decoder_t
*dec
, picture_t
*p_pic
)
303 assert( p_pic
->p_next
== NULL
);
304 assert( dec
->pf_queue_video
!= NULL
);
305 return dec
->pf_queue_video( dec
, p_pic
);
309 * This function queues the Closed Captions
311 * \param dec the decoder object
312 * \param p_cc the closed-caption to queue
313 * \param p_cc_present array-of-bool where each entry indicates whether the
314 * given channel is present or not
315 * \param i_depth the closed-caption to queue reorder depth, or simply 0
316 * if using the old mpgv block flag tagging
317 * \return 0 if queued, -1 on error
319 static inline int decoder_QueueCc( decoder_t
*dec
, block_t
*p_cc
,
320 bool p_cc_present
[4], int i_depth
)
322 if( dec
->pf_queue_cc
== NULL
)
324 block_Release( p_cc
);
327 return dec
->pf_queue_cc( dec
, p_cc
, p_cc_present
, i_depth
);
331 * This function queues a single audio block to the audio output.
334 * The caller doesn't own the audio block anymore after this call (even in case
337 * \return 0 if the block is queued, -1 on error
339 static inline int decoder_QueueAudio( decoder_t
*dec
, block_t
*p_aout_buf
)
341 assert( p_aout_buf
->p_next
== NULL
);
342 assert( dec
->pf_queue_audio
!= NULL
);
343 return dec
->pf_queue_audio( dec
, p_aout_buf
);
347 * This function queues a single subtitle to the video output.
350 * The caller doesn't own the subtitle anymore after this call (even in case of
353 * \return 0 if the subtitle is queued, -1 on error
355 static inline int decoder_QueueSub( decoder_t
*dec
, subpicture_t
*p_spu
)
357 assert( p_spu
->p_next
== NULL
);
358 assert( dec
->pf_queue_sub
!= NULL
);
359 return dec
->pf_queue_sub( dec
, p_spu
);
363 * This function notifies the audio output pipeline of a new audio output
364 * format (fmt_out.audio). If there is currently no audio output or if the
365 * audio output format has changed, a new audio output will be set up.
366 * @return 0 if the audio output is working, -1 if not. */
367 static inline int decoder_UpdateAudioFormat( decoder_t
*dec
)
369 assert(dec
->fmt_in
.i_cat
== AUDIO_ES
);
370 if( dec
->fmt_in
.i_cat
== AUDIO_ES
&& dec
->pf_aout_format_update
!= NULL
)
371 return dec
->pf_aout_format_update( dec
);
377 * This function will return a new audio buffer usable by a decoder as an
378 * output buffer. It must be released with block_Release() or returned it to
379 * the caller as a decoder_QueueAudio parameter.
381 VLC_API block_t
* decoder_NewAudioBuffer( decoder_t
*, int i_nb_samples
) VLC_USED
;
384 * This function will return a new subpicture usable by a decoder as an output
385 * buffer. You have to release it using subpicture_Delete() or by returning
386 * it to the caller as a decoder_QueueSub parameter.
388 VLC_API subpicture_t
* decoder_NewSubpicture( decoder_t
*, const subpicture_updater_t
* ) VLC_USED
;
391 * This function gives all input attachments at once.
393 * You MUST release the returned values
395 VLC_API
int decoder_GetInputAttachments( decoder_t
*, input_attachment_t
***ppp_attachment
, int *pi_attachment
);
398 * This function converts a decoder timestamp into a display date comparable
400 * You MUST use it *only* for gathering statistics about speed.
402 VLC_API mtime_t
decoder_GetDisplayDate( decoder_t
*, mtime_t
) VLC_USED
;
405 * This function returns the current input rate.
406 * You MUST use it *only* for gathering statistics about speed.
408 VLC_API
int decoder_GetDisplayRate( decoder_t
* ) VLC_USED
;
412 #endif /* _VLC_CODEC_H */