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" */
47 #include "debug.h" /* "input_netlist.h" */
49 #include "intf_msg.h" /* intf_DbgMsg(), intf_ErrMsg() */
51 #include "input.h" /* pes_packet_t */
52 #include "input_netlist.h" /* input_NetlistFreePES() */
53 #include "decoder_fifo.h" /* DECODER_FIFO_(ISEMPTY|START|INCSTART)() */
55 #include "audio_output.h"
57 #include "ac3_decoder.h"
58 #include "ac3_decoder_thread.h"
60 #define AC3DEC_FRAME_SIZE (2*1536)
61 typedef s16 ac3dec_frame_t[ AC3DEC_FRAME_SIZE ];
63 /*****************************************************************************
65 *****************************************************************************/
66 static int InitThread ( ac3dec_thread_t * p_adec );
67 static void RunThread ( ac3dec_thread_t * p_adec );
68 static void ErrorThread ( ac3dec_thread_t * p_adec );
69 static void EndThread ( ac3dec_thread_t * p_adec );
71 /*****************************************************************************
72 * ac3dec_CreateThread: creates an ac3 decoder thread
73 *****************************************************************************/
74 ac3dec_thread_t * ac3dec_CreateThread( input_thread_t * p_input )
76 ac3dec_thread_t * p_ac3dec;
78 intf_DbgMsg("ac3dec debug: creating ac3 decoder thread\n");
80 /* Allocate the memory needed to store the thread's structure */
81 if ( (p_ac3dec = (ac3dec_thread_t *)malloc( sizeof(ac3dec_thread_t) )) == NULL )
83 intf_ErrMsg("ac3dec error: not enough memory for ac3dec_CreateThread() to create the new thread\n");
88 * Initialize the thread properties
91 p_ac3dec->b_error = 0;
94 * Initialize the input properties
96 /* Initialize the decoder fifo's data lock and conditional variable and set
97 * its buffer as empty */
98 vlc_mutex_init( &p_ac3dec->fifo.data_lock );
99 vlc_cond_init( &p_ac3dec->fifo.data_wait );
100 p_ac3dec->fifo.i_start = 0;
101 p_ac3dec->fifo.i_end = 0;
103 /* Initialize the ac3 decoder structures */
104 ac3_init (&p_ac3dec->ac3_decoder);
106 /* Initialize the bit stream structure */
107 p_ac3dec->p_input = p_input;
110 * Initialize the output properties
112 p_ac3dec->p_aout = p_input->p_aout;
113 p_ac3dec->p_aout_fifo = NULL;
115 /* Spawn the ac3 decoder thread */
116 if ( vlc_thread_create(&p_ac3dec->thread_id, "ac3 decoder", (vlc_thread_func_t)RunThread, (void *)p_ac3dec) )
118 intf_ErrMsg( "ac3dec error: can't spawn ac3 decoder thread\n" );
123 intf_DbgMsg( "ac3dec debug: ac3 decoder thread (%p) created\n", p_ac3dec );
127 /*****************************************************************************
128 * ac3dec_DestroyThread: destroys an ac3 decoder thread
129 *****************************************************************************/
130 void ac3dec_DestroyThread( ac3dec_thread_t * p_ac3dec )
132 intf_DbgMsg( "ac3dec debug: requesting termination of ac3 decoder thread %p\n", p_ac3dec );
134 /* Ask thread to kill itself */
137 /* Make sure the decoder thread leaves the GetByte() function */
138 vlc_mutex_lock( &(p_ac3dec->fifo.data_lock) );
139 vlc_cond_signal( &(p_ac3dec->fifo.data_wait) );
140 vlc_mutex_unlock( &(p_ac3dec->fifo.data_lock) );
142 /* Waiting for the decoder thread to exit */
143 /* Remove this as soon as the "status" flag is implemented */
144 vlc_thread_join( p_ac3dec->thread_id );
147 /* Following functions are local */
149 /*****************************************************************************
150 * InitThread : initialize an ac3 decoder thread
151 *****************************************************************************/
152 static int InitThread( ac3dec_thread_t * p_ac3dec )
154 aout_fifo_t aout_fifo;
155 ac3_byte_stream_t * byte_stream;
157 intf_DbgMsg( "ac3dec debug: initializing ac3 decoder thread %p\n", p_ac3dec );
159 /* Our first job is to initialize the bit stream structure with the
160 * beginning of the input stream */
161 vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
162 while ( DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
164 if ( p_ac3dec->b_die )
166 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
169 vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
171 p_ac3dec->p_ts = DECODER_FIFO_START( p_ac3dec->fifo )->p_first_ts;
172 byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
173 byte_stream->p_byte =
174 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
176 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;
177 byte_stream->info = p_ac3dec;
178 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
180 aout_fifo.i_type = AOUT_ADEC_STEREO_FIFO;
181 aout_fifo.i_channels = 2;
182 aout_fifo.b_stereo = 1;
184 aout_fifo.l_frame_size = AC3DEC_FRAME_SIZE;
186 /* Creating the audio output fifo */
187 if ( (p_ac3dec->p_aout_fifo = aout_CreateFifo(p_ac3dec->p_aout, &aout_fifo)) == NULL )
192 intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p initialized\n", p_ac3dec );
196 /*****************************************************************************
197 * RunThread : ac3 decoder thread
198 *****************************************************************************/
199 static void RunThread( ac3dec_thread_t * p_ac3dec )
203 intf_DbgMsg( "ac3dec debug: running ac3 decoder thread (%p) (pid == %i)\n", p_ac3dec, getpid() );
205 msleep( INPUT_PTS_DELAY );
207 /* Initializing the ac3 decoder thread */
208 if ( InitThread(p_ac3dec) ) /* XXX?? */
210 p_ac3dec->b_error = 1;
214 p_ac3dec->sync_ptr = 0;
216 /* ac3 decoder thread's main loop */
217 /* FIXME : do we have enough room to store the decoded frames ?? */
218 while ( (!p_ac3dec->b_die) && (!p_ac3dec->b_error) )
221 ac3_sync_info_t sync_info;
223 if (!sync) { /* have to find a synchro point */
225 ac3_byte_stream_t * p_byte_stream;
229 p_byte_stream = ac3_byte_stream (&p_ac3dec->ac3_decoder);
231 /* first read till next ac3 magic header */
233 ac3_byte_stream_next (p_byte_stream);
234 } while ((!p_ac3dec->sync_ptr) &&
235 (!p_ac3dec->b_die) &&
236 (!p_ac3dec->b_error));
237 /* skip the specified number of bytes */
239 ptr = p_ac3dec->sync_ptr;
240 while (--ptr && (!p_ac3dec->b_die) && (!p_ac3dec->b_error)) {
241 if (p_byte_stream->p_byte >= p_byte_stream->p_end) {
242 ac3_byte_stream_next (p_byte_stream);
244 p_byte_stream->p_byte++;
247 /* we are in sync now */
250 p_ac3dec->sync_ptr = 0;
253 if ( DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts )
255 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = DECODER_FIFO_START(p_ac3dec->fifo)->i_pts;
256 DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts = 0;
260 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = LAST_MDATE;
263 if (ac3_sync_frame (&p_ac3dec->ac3_decoder, &sync_info)) {
268 p_ac3dec->p_aout_fifo->l_rate = sync_info.sample_rate;
270 buffer = ((ac3dec_frame_t *)p_ac3dec->p_aout_fifo->buffer)[ p_ac3dec->p_aout_fifo->l_end_frame ];
272 if (ac3_decode_frame (&p_ac3dec->ac3_decoder, buffer)) {
277 vlc_mutex_lock( &p_ac3dec->p_aout_fifo->data_lock );
278 p_ac3dec->p_aout_fifo->l_end_frame = (p_ac3dec->p_aout_fifo->l_end_frame + 1) & AOUT_FIFO_SIZE;
279 vlc_cond_signal( &p_ac3dec->p_aout_fifo->data_wait );
280 vlc_mutex_unlock( &p_ac3dec->p_aout_fifo->data_lock );
285 /* If b_error is set, the ac3 decoder thread enters the error loop */
286 if ( p_ac3dec->b_error )
288 ErrorThread( p_ac3dec );
291 /* End of the ac3 decoder thread */
292 EndThread( p_ac3dec );
295 /*****************************************************************************
296 * ErrorThread : ac3 decoder's RunThread() error loop
297 *****************************************************************************/
298 static void ErrorThread( ac3dec_thread_t * p_ac3dec )
300 /* We take the lock, because we are going to read/write the start/end
301 * indexes of the decoder fifo */
302 vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
304 /* Wait until a `die' order is sent */
305 while( !p_ac3dec->b_die )
307 /* Trash all received PES packets */
308 while( !DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
310 input_NetlistFreePES( p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo) );
311 DECODER_FIFO_INCSTART( p_ac3dec->fifo );
314 /* Waiting for the input thread to put new PES packets in the fifo */
315 vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
318 /* We can release the lock before leaving */
319 vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
322 /*****************************************************************************
323 * EndThread : ac3 decoder thread destruction
324 *****************************************************************************/
325 static void EndThread( ac3dec_thread_t * p_ac3dec )
327 intf_DbgMsg( "ac3dec debug: destroying ac3 decoder thread %p\n", p_ac3dec );
329 /* If the audio output fifo was created, we destroy it */
330 if ( p_ac3dec->p_aout_fifo != NULL )
332 aout_DestroyFifo( p_ac3dec->p_aout_fifo );
334 /* Make sure the output thread leaves the NextFrame() function */
335 vlc_mutex_lock( &(p_ac3dec->p_aout_fifo->data_lock) );
336 vlc_cond_signal( &(p_ac3dec->p_aout_fifo->data_wait) );
337 vlc_mutex_unlock( &(p_ac3dec->p_aout_fifo->data_lock) );
340 /* Destroy descriptor */
343 intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p destroyed\n", p_ac3dec );
346 void ac3_byte_stream_next (ac3_byte_stream_t * p_byte_stream)
348 ac3dec_thread_t * p_ac3dec = p_byte_stream->info;
350 /* We are looking for the next TS packet that contains real data,
351 * and not just a PES header */
353 /* We were reading the last TS packet of this PES packet... It's
354 * time to jump to the next PES packet */
355 if (p_ac3dec->p_ts->p_next_ts == NULL) {
358 /* We are going to read/write the start and end indexes of the
359 * decoder fifo and to use the fifo's conditional variable,
360 * that's why we need to take the lock before */
361 vlc_mutex_lock (&p_ac3dec->fifo.data_lock);
363 /* Is the input thread dying ? */
364 if (p_ac3dec->p_input->b_die) {
365 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
369 /* We should increase the start index of the decoder fifo, but
370 * if we do this now, the input thread could overwrite the
371 * pointer to the current PES packet, and we weren't able to
372 * give it back to the netlist. That's why we free the PES
374 input_NetlistFreePES (p_ac3dec->p_input, DECODER_FIFO_START(p_ac3dec->fifo) );
376 DECODER_FIFO_INCSTART (p_ac3dec->fifo);
378 while (DECODER_FIFO_ISEMPTY(p_ac3dec->fifo)) {
379 vlc_cond_wait (&p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
381 if (p_ac3dec->p_input->b_die) {
382 vlc_mutex_unlock (&(p_ac3dec->fifo.data_lock));
387 /* The next byte could be found in the next PES packet */
388 p_ac3dec->p_ts = DECODER_FIFO_START (p_ac3dec->fifo)->p_first_ts;
390 /* parse ac3 magic header */
391 ptr = p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+2];
393 ptr |= p_ac3dec->p_ts->buffer [p_ac3dec->p_ts->i_payload_start+3];
394 p_ac3dec->sync_ptr = ptr;
395 p_ac3dec->p_ts->i_payload_start += 4;
397 /* We can release the fifo's data lock */
398 vlc_mutex_unlock (&p_ac3dec->fifo.data_lock);
401 /* Perhaps the next TS packet of the current PES packet contains
402 * real data (ie its payload's size is greater than 0) */
404 p_ac3dec->p_ts = p_ac3dec->p_ts->p_next_ts;
406 } while (p_ac3dec->p_ts->i_payload_start == p_ac3dec->p_ts->i_payload_end);
407 p_byte_stream->p_byte =
408 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_start;
409 p_byte_stream->p_end =
410 p_ac3dec->p_ts->buffer + p_ac3dec->p_ts->i_payload_end;