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 GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public
19 * License along with this program; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
22 *****************************************************************************/
27 * - vérifier l'état de la fifo de sortie avant d'y stocker les samples
29 * - vlc_cond_signal() / vlc_cond_wait()
33 /*****************************************************************************
35 *****************************************************************************/
36 #include <unistd.h> /* getpid() */
38 #include <stdio.h> /* "intf_msg.h" */
39 #include <stdlib.h> /* malloc(), free() */
40 #include <sys/types.h> /* on BSD, uio.h needs types.h */
41 #include <sys/uio.h> /* "input.h" */
48 #include "debug.h" /* "input_netlist.h" */
50 #include "intf_msg.h" /* intf_DbgMsg(), intf_ErrMsg() */
52 #include "input.h" /* pes_packet_t */
53 #include "input_netlist.h" /* input_NetlistFreePES() */
54 #include "decoder_fifo.h" /* DECODER_FIFO_(ISEMPTY|START|INCSTART)() */
56 #include "audio_output.h"
58 #include "ac3_decoder.h"
59 #include "ac3_decoder_thread.h"
61 #define AC3DEC_FRAME_SIZE (2*1536)
62 typedef s16 ac3dec_frame_t[ AC3DEC_FRAME_SIZE ];
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 for ac3dec_CreateThread() to create the new thread\n");
89 * Initialize the thread properties
92 p_ac3dec->b_error = 0;
95 * Initialize the input properties
97 /* Initialize the decoder fifo's data lock and conditional variable and set
98 * its buffer as empty */
99 vlc_mutex_init( &p_ac3dec->fifo.data_lock );
100 vlc_cond_init( &p_ac3dec->fifo.data_wait );
101 p_ac3dec->fifo.i_start = 0;
102 p_ac3dec->fifo.i_end = 0;
104 /* Initialize the ac3 decoder structures */
105 ac3_init (&p_ac3dec->ac3_decoder);
107 /* Initialize the bit stream structure */
108 p_ac3dec->p_input = p_input;
111 * Initialize the output properties
113 p_ac3dec->p_aout = p_input->p_aout;
114 p_ac3dec->p_aout_fifo = NULL;
116 /* Spawn the ac3 decoder thread */
117 if ( vlc_thread_create(&p_ac3dec->thread_id, "ac3 decoder", (vlc_thread_func_t)RunThread, (void *)p_ac3dec) )
119 intf_ErrMsg( "ac3dec error: can't spawn ac3 decoder thread\n" );
124 intf_DbgMsg( "ac3dec debug: ac3 decoder thread (%p) created\n", p_ac3dec );
128 /*****************************************************************************
129 * ac3dec_DestroyThread: destroys an ac3 decoder thread
130 *****************************************************************************/
131 void ac3dec_DestroyThread( ac3dec_thread_t * p_ac3dec )
133 intf_DbgMsg( "ac3dec debug: requesting termination of ac3 decoder thread %p\n", p_ac3dec );
135 /* Ask thread to kill itself */
138 /* Make sure the decoder thread leaves the GetByte() function */
139 vlc_mutex_lock( &(p_ac3dec->fifo.data_lock) );
140 vlc_cond_signal( &(p_ac3dec->fifo.data_wait) );
141 vlc_mutex_unlock( &(p_ac3dec->fifo.data_lock) );
143 /* Waiting for the decoder thread to exit */
144 /* Remove this as soon as the "status" flag is implemented */
145 vlc_thread_join( p_ac3dec->thread_id );
148 /* Following functions are local */
150 /*****************************************************************************
151 * InitThread : initialize an ac3 decoder thread
152 *****************************************************************************/
153 static int InitThread( ac3dec_thread_t * p_ac3dec )
155 aout_fifo_t aout_fifo;
156 ac3_byte_stream_t * byte_stream;
158 intf_DbgMsg( "ac3dec debug: initializing ac3 decoder thread %p\n", p_ac3dec );
160 /* Our first job is to initialize the bit stream structure with the
161 * beginning of the input stream */
162 vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
163 while ( DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
165 if ( p_ac3dec->b_die )
167 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
170 vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
172 p_ac3dec->p_ts = DECODER_FIFO_START( p_ac3dec->fifo )->p_first_ts;
173 byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
174 byte_stream->p_byte =
175 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
177 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;
178 byte_stream->info = p_ac3dec;
179 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
181 aout_fifo.i_type = AOUT_ADEC_STEREO_FIFO;
182 aout_fifo.i_channels = 2;
183 aout_fifo.b_stereo = 1;
185 aout_fifo.l_frame_size = AC3DEC_FRAME_SIZE;
187 /* Creating the audio output fifo */
188 if ( (p_ac3dec->p_aout_fifo = aout_CreateFifo(p_ac3dec->p_aout, &aout_fifo)) == NULL )
193 intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p initialized\n", p_ac3dec );
197 /*****************************************************************************
198 * RunThread : ac3 decoder thread
199 *****************************************************************************/
200 static void RunThread( ac3dec_thread_t * p_ac3dec )
204 intf_DbgMsg( "ac3dec debug: running ac3 decoder thread (%p) (pid == %i)\n", p_ac3dec, getpid() );
206 msleep( INPUT_PTS_DELAY );
208 /* Initializing the ac3 decoder thread */
209 if ( InitThread(p_ac3dec) ) /* XXX?? */
211 p_ac3dec->b_error = 1;
215 p_ac3dec->sync_ptr = 0;
217 /* ac3 decoder thread's main loop */
218 /* FIXME : do we have enough room to store the decoded frames ?? */
219 while ( (!p_ac3dec->b_die) && (!p_ac3dec->b_error) )
222 ac3_sync_info_t sync_info;
224 if (!sync) { /* have to find a synchro point */
226 ac3_byte_stream_t * p_byte_stream;
230 p_byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
232 /* first read till next ac3 magic header */
234 ac3_byte_stream_next (p_byte_stream);
235 } while ((!p_ac3dec->sync_ptr) &&
236 (!p_ac3dec->b_die) &&
237 (!p_ac3dec->b_error));
238 /* skip the specified number of bytes */
240 ptr = p_ac3dec->sync_ptr;
241 while (--ptr && (!p_ac3dec->b_die) && (!p_ac3dec->b_error)) {
242 if (p_byte_stream->p_byte >= p_byte_stream->p_end) {
243 ac3_byte_stream_next (p_byte_stream);
245 p_byte_stream->p_byte++;
248 /* we are in sync now */
251 p_ac3dec->sync_ptr = 0;
254 if ( DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts )
256 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = DECODER_FIFO_START(p_ac3dec->fifo)->i_pts;
257 DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts = 0;
261 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = LAST_MDATE;
264 if (ac3_sync_frame (&p_ac3dec->ac3_decoder, &sync_info)) {
269 p_ac3dec->p_aout_fifo->l_rate = sync_info.sample_rate;
271 buffer = ((ac3dec_frame_t *)p_ac3dec->p_aout_fifo->buffer)[ p_ac3dec->p_aout_fifo->l_end_frame ];
273 if (ac3_decode_frame (&p_ac3dec->ac3_decoder, buffer)) {
278 vlc_mutex_lock( &p_ac3dec->p_aout_fifo->data_lock );
279 p_ac3dec->p_aout_fifo->l_end_frame = (p_ac3dec->p_aout_fifo->l_end_frame + 1) & AOUT_FIFO_SIZE;
280 vlc_cond_signal( &p_ac3dec->p_aout_fifo->data_wait );
281 vlc_mutex_unlock( &p_ac3dec->p_aout_fifo->data_lock );
286 /* If b_error is set, the ac3 decoder thread enters the error loop */
287 if ( p_ac3dec->b_error )
289 ErrorThread( p_ac3dec );
292 /* End of the ac3 decoder thread */
293 EndThread( p_ac3dec );
296 /*****************************************************************************
297 * ErrorThread : ac3 decoder's RunThread() error loop
298 *****************************************************************************/
299 static void ErrorThread( ac3dec_thread_t * p_ac3dec )
301 /* We take the lock, because we are going to read/write the start/end
302 * indexes of the decoder fifo */
303 vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
305 /* Wait until a `die' order is sent */
306 while( !p_ac3dec->b_die )
308 /* Trash all received PES packets */
309 while( !DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
311 input_NetlistFreePES( p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo) );
312 DECODER_FIFO_INCSTART( p_ac3dec->fifo );
315 /* Waiting for the input thread to put new PES packets in the fifo */
316 vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
319 /* We can release the lock before leaving */
320 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
323 /*****************************************************************************
324 * EndThread : ac3 decoder thread destruction
325 *****************************************************************************/
326 static void EndThread( ac3dec_thread_t * p_ac3dec )
328 intf_DbgMsg( "ac3dec debug: destroying ac3 decoder thread %p\n", p_ac3dec );
330 /* If the audio output fifo was created, we destroy it */
331 if ( p_ac3dec->p_aout_fifo != NULL )
333 aout_DestroyFifo( p_ac3dec->p_aout_fifo );
335 /* Make sure the output thread leaves the NextFrame() function */
336 vlc_mutex_lock( &(p_ac3dec->p_aout_fifo->data_lock) );
337 vlc_cond_signal( &(p_ac3dec->p_aout_fifo->data_wait) );
338 vlc_mutex_unlock( &(p_ac3dec->p_aout_fifo->data_lock) );
341 /* Destroy descriptor */
344 intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p destroyed\n", p_ac3dec );
347 void ac3_byte_stream_next (ac3_byte_stream_t * p_byte_stream)
349 ac3dec_thread_t * p_ac3dec = p_byte_stream->info;
351 /* We are looking for the next TS packet that contains real data,
352 * and not just a PES header */
354 /* We were reading the last TS packet of this PES packet... It's
355 * time to jump to the next PES packet */
356 if (p_ac3dec->p_ts->p_next_ts == NULL) {
359 /* We are going to read/write the start and end indexes of the
360 * decoder fifo and to use the fifo's conditional variable,
361 * that's why we need to take the lock before */
362 vlc_mutex_lock (&p_ac3dec->fifo.data_lock);
364 /* Is the input thread dying ? */
365 if (p_ac3dec->p_input->b_die) {
366 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
370 /* We should increase the start index of the decoder fifo, but
371 * if we do this now, the input thread could overwrite the
372 * pointer to the current PES packet, and we weren't able to
373 * give it back to the netlist. That's why we free the PES
375 input_NetlistFreePES (p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo) );
377 DECODER_FIFO_INCSTART (p_ac3dec->fifo);
379 while (DECODER_FIFO_ISEMPTY(p_ac3dec->fifo)) {
380 vlc_cond_wait (&p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
382 if (p_ac3dec->p_input->b_die) {
383 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
388 /* The next byte could be found in the next PES packet */
389 p_ac3dec->p_ts = DECODER_FIFO_START (p_ac3dec->fifo)->p_first_ts;
391 /* parse ac3 magic header */
392 ptr = p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+2];
394 ptr |= p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+3];
395 p_ac3dec->sync_ptr = ptr;
396 p_ac3dec->p_ts->i_payload_start += 4;
398 /* We can release the fifo's data lock */
399 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
402 /* Perhaps the next TS packet of the current PES packet contains
403 * real data (ie its payload's size is greater than 0) */
405 p_ac3dec->p_ts = p_ac3dec->p_ts->p_next_ts;
407 } while (p_ac3dec->p_ts->i_payload_start == p_ac3dec->p_ts->i_payload_end);
408 p_byte_stream->p_byte =
409 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
410 p_byte_stream->p_end =
411 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;