1 /*****************************************************************************
2 * ac3_decoder_thread.c: ac3 decoder thread
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
21 *****************************************************************************/
26 * - vérifier l'état de la fifo de sortie avant d'y stocker les samples
28 * - vlc_cond_signal() / vlc_cond_wait()
32 /*****************************************************************************
34 *****************************************************************************/
37 #include <unistd.h> /* getpid() */
39 #include <stdio.h> /* "intf_msg.h" */
40 #include <stdlib.h> /* malloc(), free() */
41 #include <sys/types.h> /* on BSD, uio.h needs types.h */
42 #include <sys/uio.h> /* "input.h" */
49 #include "debug.h" /* "input_netlist.h" */
51 #include "intf_msg.h" /* intf_DbgMsg(), intf_ErrMsg() */
53 #include "input.h" /* pes_packet_t */
54 #include "input_netlist.h" /* input_NetlistFreePES() */
55 #include "decoder_fifo.h" /* DECODER_FIFO_(ISEMPTY|START|INCSTART)() */
57 #include "audio_output.h"
59 #include "ac3_decoder.h"
60 #include "ac3_decoder_thread.h"
62 #define AC3DEC_FRAME_SIZE (2*1536)
64 /*****************************************************************************
66 *****************************************************************************/
67 static int InitThread (ac3dec_thread_t * p_adec);
68 static void RunThread (ac3dec_thread_t * p_adec);
69 static void ErrorThread (ac3dec_thread_t * p_adec);
70 static void EndThread (ac3dec_thread_t * p_adec);
72 /*****************************************************************************
73 * ac3dec_CreateThread: creates an ac3 decoder thread
74 *****************************************************************************/
75 ac3dec_thread_t * ac3dec_CreateThread (input_thread_t * p_input)
77 ac3dec_thread_t * p_ac3dec;
79 intf_DbgMsg( "ac3dec debug: creating ac3 decoder thread\n" );
81 /* Allocate the memory needed to store the thread's structure */
82 if ((p_ac3dec = (ac3dec_thread_t *)malloc (sizeof(ac3dec_thread_t))) == NULL)
84 intf_ErrMsg ( "ac3dec error: not enough memory "
85 "for ac3dec_CreateThread() to create the new thread\n");
90 * Initialize the thread properties
93 p_ac3dec->b_error = 0;
96 * Initialize the input properties
98 /* Initialize the decoder fifo's data lock and conditional variable and set
99 * its buffer as empty */
100 vlc_mutex_init (&p_ac3dec->fifo.data_lock);
101 vlc_cond_init (&p_ac3dec->fifo.data_wait);
102 p_ac3dec->fifo.i_start = 0;
103 p_ac3dec->fifo.i_end = 0;
105 /* Initialize the ac3 decoder structures */
106 ac3_init (&p_ac3dec->ac3_decoder);
108 /* Initialize the bit stream structure */
109 p_ac3dec->p_input = p_input;
112 * Initialize the output properties
114 p_ac3dec->p_aout = p_input->p_aout;
115 p_ac3dec->p_aout_fifo = NULL;
117 /* Spawn the ac3 decoder thread */
118 if (vlc_thread_create(&p_ac3dec->thread_id, "ac3 decoder", (vlc_thread_func_t)RunThread, (void *)p_ac3dec))
120 intf_ErrMsg( "ac3dec error: can't spawn ac3 decoder thread\n" );
125 intf_DbgMsg ("ac3dec debug: ac3 decoder thread (%p) created\n", p_ac3dec);
129 /*****************************************************************************
130 * ac3dec_DestroyThread: destroys an ac3 decoder thread
131 *****************************************************************************/
132 void ac3dec_DestroyThread (ac3dec_thread_t * p_ac3dec)
134 intf_DbgMsg ("ac3dec debug: requesting termination of ac3 decoder thread %p\n", p_ac3dec);
136 /* Ask thread to kill itself */
139 /* Make sure the decoder thread leaves the GetByte() function */
140 vlc_mutex_lock (&(p_ac3dec->fifo.data_lock));
141 vlc_cond_signal (&(p_ac3dec->fifo.data_wait));
142 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
144 /* Waiting for the decoder thread to exit */
145 /* Remove this as soon as the "status" flag is implemented */
146 vlc_thread_join (p_ac3dec->thread_id);
149 /* Following functions are local */
151 /*****************************************************************************
152 * InitThread : initialize an ac3 decoder thread
153 *****************************************************************************/
154 static int InitThread (ac3dec_thread_t * p_ac3dec)
156 aout_fifo_t aout_fifo;
157 ac3_byte_stream_t * byte_stream;
159 intf_DbgMsg ("ac3dec debug: initializing ac3 decoder thread %p\n", p_ac3dec);
161 /* Our first job is to initialize the bit stream structure with the
162 * beginning of the input stream */
163 vlc_mutex_lock (&p_ac3dec->fifo.data_lock);
164 while (DECODER_FIFO_ISEMPTY(p_ac3dec->fifo))
168 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
171 vlc_cond_wait (&p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock);
173 p_ac3dec->p_ts = DECODER_FIFO_START (p_ac3dec->fifo)->p_first_ts;
174 byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
175 byte_stream->p_byte =
176 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
178 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;
179 byte_stream->info = p_ac3dec;
180 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
182 aout_fifo.i_type = AOUT_ADEC_STEREO_FIFO;
183 aout_fifo.i_channels = 2;
184 aout_fifo.b_stereo = 1;
186 aout_fifo.l_frame_size = AC3DEC_FRAME_SIZE;
188 /* Creating the audio output fifo */
189 if ((p_ac3dec->p_aout_fifo = aout_CreateFifo(p_ac3dec->p_aout, &aout_fifo)) == NULL)
194 intf_DbgMsg ("ac3dec debug: ac3 decoder thread %p initialized\n", p_ac3dec);
198 /*****************************************************************************
199 * RunThread : ac3 decoder thread
200 *****************************************************************************/
201 static void RunThread (ac3dec_thread_t * p_ac3dec)
205 intf_DbgMsg ("ac3dec debug: running ac3 decoder thread (%p) (pid == %i)\n", p_ac3dec, getpid());
207 msleep (INPUT_PTS_DELAY);
209 /* Initializing the ac3 decoder thread */
210 if (InitThread (p_ac3dec)) /* XXX?? */
212 p_ac3dec->b_error = 1;
216 p_ac3dec->sync_ptr = 0;
218 /* ac3 decoder thread's main loop */
219 /* FIXME : do we have enough room to store the decoded frames ?? */
220 while ((!p_ac3dec->b_die) && (!p_ac3dec->b_error))
223 ac3_sync_info_t sync_info;
225 if (!sync) { /* have to find a synchro point */
227 ac3_byte_stream_t * p_byte_stream;
229 intf_DbgMsg ("ac3dec: sync\n");
231 p_byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
233 /* first read till next ac3 magic header */
236 ac3_byte_stream_next (p_byte_stream);
237 } while ((!p_ac3dec->sync_ptr) &&
238 (!p_ac3dec->b_die) &&
239 (!p_ac3dec->b_error));
240 /* skip the specified number of bytes */
242 if( p_ac3dec->b_die || p_ac3dec->b_error )
247 ptr = p_ac3dec->sync_ptr;
248 while (--ptr && (!p_ac3dec->b_die) && (!p_ac3dec->b_error))
250 if (p_byte_stream->p_byte >= p_byte_stream->p_end)
252 ac3_byte_stream_next (p_byte_stream);
254 p_byte_stream->p_byte++;
257 if( p_ac3dec->b_die || p_ac3dec->b_error )
262 /* we are in sync now */
264 p_ac3dec->sync_ptr = 0;
267 if (DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts)
269 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = DECODER_FIFO_START(p_ac3dec->fifo)->i_pts;
270 DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts = 0;
274 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = LAST_MDATE;
277 if (ac3_sync_frame (&p_ac3dec->ac3_decoder, &sync_info))
283 p_ac3dec->p_aout_fifo->l_rate = sync_info.sample_rate;
285 buffer = ((s16 *)p_ac3dec->p_aout_fifo->buffer) + (p_ac3dec->p_aout_fifo->l_end_frame * AC3DEC_FRAME_SIZE);
287 if (ac3_decode_frame (&p_ac3dec->ac3_decoder, buffer))
293 vlc_mutex_lock (&p_ac3dec->p_aout_fifo->data_lock);
294 p_ac3dec->p_aout_fifo->l_end_frame = (p_ac3dec->p_aout_fifo->l_end_frame + 1) & AOUT_FIFO_SIZE;
295 vlc_cond_signal (&p_ac3dec->p_aout_fifo->data_wait);
296 vlc_mutex_unlock (&p_ac3dec->p_aout_fifo->data_lock);
301 /* If b_error is set, the ac3 decoder thread enters the error loop */
302 if (p_ac3dec->b_error)
304 ErrorThread (p_ac3dec);
307 /* End of the ac3 decoder thread */
308 EndThread (p_ac3dec);
311 /*****************************************************************************
312 * ErrorThread : ac3 decoder's RunThread() error loop
313 *****************************************************************************/
314 static void ErrorThread (ac3dec_thread_t * p_ac3dec)
316 /* We take the lock, because we are going to read/write the start/end
317 * indexes of the decoder fifo */
318 vlc_mutex_lock (&p_ac3dec->fifo.data_lock);
320 /* Wait until a `die' order is sent */
321 while (!p_ac3dec->b_die)
323 /* Trash all received PES packets */
324 while (!DECODER_FIFO_ISEMPTY(p_ac3dec->fifo))
326 input_NetlistFreePES (p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo));
327 DECODER_FIFO_INCSTART (p_ac3dec->fifo);
330 /* Waiting for the input thread to put new PES packets in the fifo */
331 vlc_cond_wait (&p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock);
334 /* We can release the lock before leaving */
335 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
338 /*****************************************************************************
339 * EndThread : ac3 decoder thread destruction
340 *****************************************************************************/
341 static void EndThread (ac3dec_thread_t * p_ac3dec)
343 intf_DbgMsg ("ac3dec debug: destroying ac3 decoder thread %p\n", p_ac3dec);
345 /* If the audio output fifo was created, we destroy it */
346 if (p_ac3dec->p_aout_fifo != NULL)
348 aout_DestroyFifo (p_ac3dec->p_aout_fifo);
350 /* Make sure the output thread leaves the NextFrame() function */
351 vlc_mutex_lock (&(p_ac3dec->p_aout_fifo->data_lock));
352 vlc_cond_signal (&(p_ac3dec->p_aout_fifo->data_wait));
353 vlc_mutex_unlock (&(p_ac3dec->p_aout_fifo->data_lock));
356 /* Destroy descriptor */
359 intf_DbgMsg ("ac3dec debug: ac3 decoder thread %p destroyed\n", p_ac3dec);
362 void ac3_byte_stream_next (ac3_byte_stream_t * p_byte_stream)
364 ac3dec_thread_t * p_ac3dec = p_byte_stream->info;
366 /* We are looking for the next TS packet that contains real data,
367 * and not just a PES header */
370 /* We were reading the last TS packet of this PES packet... It's
371 * time to jump to the next PES packet */
372 if (p_ac3dec->p_ts->p_next_ts == NULL)
376 /* We are going to read/write the start and end indexes of the
377 * decoder fifo and to use the fifo's conditional variable,
378 * that's why we need to take the lock before */
379 vlc_mutex_lock (&p_ac3dec->fifo.data_lock);
381 /* Is the input thread dying ? */
382 if (p_ac3dec->p_input->b_die)
384 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
388 /* We should increase the start index of the decoder fifo, but
389 * if we do this now, the input thread could overwrite the
390 * pointer to the current PES packet, and we weren't able to
391 * give it back to the netlist. That's why we free the PES
393 input_NetlistFreePES (p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo));
395 DECODER_FIFO_INCSTART (p_ac3dec->fifo);
397 while (DECODER_FIFO_ISEMPTY(p_ac3dec->fifo))
399 vlc_cond_wait (&p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock);
401 if (p_ac3dec->p_input->b_die)
403 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
408 /* The next byte could be found in the next PES packet */
409 p_ac3dec->p_ts = DECODER_FIFO_START (p_ac3dec->fifo)->p_first_ts;
411 /* parse ac3 magic header */
412 ptr = p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+2];
414 ptr |= p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+3];
415 p_ac3dec->sync_ptr = ptr;
416 p_ac3dec->p_ts->i_payload_start += 4;
418 /* We can release the fifo's data lock */
419 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
421 /* Perhaps the next TS packet of the current PES packet contains
422 * real data (ie its payload's size is greater than 0) */
425 p_ac3dec->p_ts = p_ac3dec->p_ts->p_next_ts;
427 } while (p_ac3dec->p_ts->i_payload_start == p_ac3dec->p_ts->i_payload_end);
428 p_byte_stream->p_byte =
429 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
430 p_byte_stream->p_end =
431 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;