git.sesse.net Git - vlc/blob - src/ac3_decoder/ac3_decoder_thread.c

   1 /*****************************************************************************
   2  * ac3_decoder.c: ac3 decoder thread
   3  * (c)1999 VideoLAN
   4  *****************************************************************************/
   5
   6 /*
   7  * TODO :
   8  *
   9  * - vérifier l'état de la fifo de sortie avant d'y stocker les samples
  10  *   décodés ;
  11  * - vlc_cond_signal() / vlc_cond_wait()
  12  *
  13  */
  14
  15 /*****************************************************************************
  16  * Preamble
  17  *****************************************************************************/
  18 #include <sys/types.h>
  19 #include <sys/stat.h>
  20 #include <fcntl.h>
  21
  22 #include <unistd.h>                                              /* getpid() */
  23
  24 #include <stdio.h>                                           /* "intf_msg.h" */
  25 #include <stdlib.h>                                      /* malloc(), free() */
  26 #include <sys/soundcard.h>                               /* "audio_output.h" */
  27 #include <sys/uio.h>                                            /* "input.h" */
  28
  29 #include "common.h"
  30 #include "config.h"
  31 #include "mtime.h"
  32 #include "vlc_thread.h"
  33 #include "debug.h"                                      /* "input_netlist.h" */
  34
  35 #include "intf_msg.h"                        /* intf_DbgMsg(), intf_ErrMsg() */
  36
  37 #include "input.h"                                           /* pes_packet_t */
  38 #include "input_netlist.h"                         /* input_NetlistFreePES() */
  39 #include "decoder_fifo.h"         /* DECODER_FIFO_(ISEMPTY|START|INCSTART)() */
  40
  41 #include "audio_output.h"
  42
  43 #include "ac3_decoder.h"
  44 #include "ac3_decoder_thread.h"
  45 #include "ac3_parse.h"
  46 #include "ac3_imdct.h"
  47
  48 /*****************************************************************************
  49  * Local prototypes
  50  *****************************************************************************/
  51 static int      InitThread              ( ac3dec_thread_t * p_adec );
  52 static void     RunThread               ( ac3dec_thread_t * p_adec );
  53 static void     ErrorThread             ( ac3dec_thread_t * p_adec );
  54 static void     EndThread               ( ac3dec_thread_t * p_adec );
  55
  56 /*****************************************************************************
  57  * ac3dec_CreateThread: creates an ac3 decoder thread
  58  *****************************************************************************/
  59 ac3dec_thread_t * ac3dec_CreateThread( input_thread_t * p_input )
  60 {
  61     ac3dec_thread_t *   p_ac3dec;
  62
  63     intf_DbgMsg("ac3dec debug: creating ac3 decoder thread\n");
  64
  65     /* Allocate the memory needed to store the thread's structure */
  66     if ( (p_ac3dec = (ac3dec_thread_t *)malloc( sizeof(ac3dec_thread_t) )) == NULL )
  67     {
  68         intf_ErrMsg("ac3dec error: not enough memory for ac3dec_CreateThread() to create the new thread\n");
  69         return( NULL );
  70     }
  71
  72     /*
  73      * Initialize the thread properties
  74      */
  75     p_ac3dec->b_die = 0;
  76     p_ac3dec->b_error = 0;
  77
  78     /*
  79      * Initialize the input properties
  80      */
  81     /* Initialize the decoder fifo's data lock and conditional variable and set
  82      * its buffer as empty */
  83     vlc_mutex_init( &p_ac3dec->fifo.data_lock );
  84     vlc_cond_init( &p_ac3dec->fifo.data_wait );
  85     p_ac3dec->fifo.i_start = 0;
  86     p_ac3dec->fifo.i_end = 0;
  87     /* Initialize the bit stream structure */
  88     p_ac3dec->ac3_decoder.bit_stream.p_input = p_input;
  89     p_ac3dec->ac3_decoder.bit_stream.p_decoder_fifo = &p_ac3dec->fifo;
  90     p_ac3dec->ac3_decoder.bit_stream.fifo.buffer = 0;
  91     p_ac3dec->ac3_decoder.bit_stream.fifo.i_available = 0;
  92
  93     /*
  94      * Initialize the output properties
  95      */
  96     p_ac3dec->p_aout = p_input->p_aout;
  97     p_ac3dec->p_aout_fifo = NULL;
  98
  99     imdct_init();
 100
 101     /* Spawn the ac3 decoder thread */
 102     if ( vlc_thread_create(&p_ac3dec->thread_id, "ac3 decoder", (vlc_thread_func_t)RunThread, (void *)p_ac3dec) )
 103     {
 104         intf_ErrMsg( "ac3dec error: can't spawn ac3 decoder thread\n" );
 105         free( p_ac3dec );
 106         return( NULL );
 107     }
 108
 109     intf_DbgMsg( "ac3dec debug: ac3 decoder thread (%p) created\n", p_ac3dec );
 110     return( p_ac3dec );
 111 }
 112
 113 /*****************************************************************************
 114  * ac3dec_DestroyThread: destroys an ac3 decoder thread
 115  *****************************************************************************/
 116 void ac3dec_DestroyThread( ac3dec_thread_t * p_ac3dec )
 117 {
 118     intf_DbgMsg( "ac3dec debug: requesting termination of ac3 decoder thread %p\n", p_ac3dec );
 119
 120     /* Ask thread to kill itself */
 121     p_ac3dec->b_die = 1;
 122
 123     /* Make sure the decoder thread leaves the GetByte() function */
 124     vlc_mutex_lock( &(p_ac3dec->fifo.data_lock) );
 125     vlc_cond_signal( &(p_ac3dec->fifo.data_wait) );
 126     vlc_mutex_unlock( &(p_ac3dec->fifo.data_lock) );
 127
 128     /* Waiting for the decoder thread to exit */
 129     /* Remove this as soon as the "status" flag is implemented */
 130     vlc_thread_join( p_ac3dec->thread_id );
 131 }
 132
 133 /* Following functions are local */
 134
 135 /*****************************************************************************
 136  * decode_find_sync()
 137  *****************************************************************************/
 138 static __inline__ int decode_find_sync( ac3dec_thread_t * p_ac3dec )
 139 {
 140     while ( (!p_ac3dec->b_die) && (!p_ac3dec->b_error) )
 141     {
 142         NeedBits( &(p_ac3dec->ac3_decoder.bit_stream), 16 );
 143         if ( (p_ac3dec->ac3_decoder.bit_stream.fifo.buffer >> (32 - 16)) == 0x0b77 )
 144         {
 145             DumpBits( &(p_ac3dec->ac3_decoder.bit_stream), 16 );
 146             p_ac3dec->ac3_decoder.total_bits_read = 16;
 147             return( 0 );
 148         }
 149         DumpBits( &(p_ac3dec->ac3_decoder.bit_stream), 1 ); /* XXX */
 150     }
 151     return( -1 );
 152 }
 153
 154 /*****************************************************************************
 155  * InitThread : initialize an ac3 decoder thread
 156  *****************************************************************************/
 157 static int InitThread( ac3dec_thread_t * p_ac3dec )
 158 {
 159     aout_fifo_t         aout_fifo;
 160
 161     intf_DbgMsg( "ac3dec debug: initializing ac3 decoder thread %p\n", p_ac3dec );
 162
 163     /* Our first job is to initialize the bit stream structure with the
 164      * beginning of the input stream */
 165     vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
 166     while ( DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
 167     {
 168         if ( p_ac3dec->b_die )
 169         {
 170             vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
 171             return( -1 );
 172         }
 173         vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
 174     }
 175     p_ac3dec->ac3_decoder.bit_stream.p_ts = DECODER_FIFO_START( p_ac3dec->fifo )->p_first_ts;
 176     p_ac3dec->ac3_decoder.bit_stream.p_byte = p_ac3dec->ac3_decoder.bit_stream.p_ts->buffer + p_ac3dec->ac3_decoder.bit_stream.p_ts->i_payload_start;
 177     p_ac3dec->ac3_decoder.bit_stream.p_end = p_ac3dec->ac3_decoder.bit_stream.p_ts->buffer + p_ac3dec->ac3_decoder.bit_stream.p_ts->i_payload_end;
 178     vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
 179
 180     aout_fifo.i_type = AOUT_ADEC_STEREO_FIFO;
 181     aout_fifo.i_channels = 2;
 182     aout_fifo.b_stereo = 1;
 183
 184     aout_fifo.l_frame_size = AC3DEC_FRAME_SIZE;
 185
 186     /* Creating the audio output fifo */
 187     if ( (p_ac3dec->p_aout_fifo = aout_CreateFifo(p_ac3dec->p_aout, &aout_fifo)) == NULL )
 188     {
 189         return( -1 );
 190     }
 191
 192     intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p initialized\n", p_ac3dec );
 193     return( 0 );
 194 }
 195
 196 /*****************************************************************************
 197  * RunThread : ac3 decoder thread
 198  *****************************************************************************/
 199 static void RunThread( ac3dec_thread_t * p_ac3dec )
 200 {
 201     intf_DbgMsg( "ac3dec debug: running ac3 decoder thread (%p) (pid == %i)\n", p_ac3dec, getpid() );
 202
 203     msleep( INPUT_PTS_DELAY );
 204
 205     /* Initializing the ac3 decoder thread */
 206     if ( InitThread(p_ac3dec) ) /* XXX */
 207     {
 208         p_ac3dec->b_error = 1;
 209     }
 210
 211     /* ac3 decoder thread's main loop */
 212     /* FIXME : do we have enough room to store the decoded frames ? */
 213     while ( (!p_ac3dec->b_die) && (!p_ac3dec->b_error) )
 214     {
 215         int i;
 216
 217         p_ac3dec->ac3_decoder.b_invalid = 0;
 218
 219         decode_find_sync( p_ac3dec );
 220
 221         if ( DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts )
 222         {
 223                 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = DECODER_FIFO_START(p_ac3dec->fifo)->i_pts;
 224                 DECODER_FIFO_START(p_ac3dec->fifo)->b_has_pts = 0;
 225         }
 226         else
 227         {
 228                 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = LAST_MDATE;
 229         }
 230
 231         parse_syncinfo( &p_ac3dec->ac3_decoder );
 232         switch ( p_ac3dec->ac3_decoder.syncinfo.fscod )
 233         {
 234                 case 0:
 235                         p_ac3dec->p_aout_fifo->l_rate = 48000;
 236                         break;
 237
 238                 case 1:
 239                         p_ac3dec->p_aout_fifo->l_rate = 44100;
 240                         break;
 241
 242                 case 2:
 243                         p_ac3dec->p_aout_fifo->l_rate = 32000;
 244                         break;
 245
 246                 default: /* XXX */
 247                         fprintf( stderr, "ac3dec debug: invalid fscod\n" );
 248                         p_ac3dec->ac3_decoder.b_invalid = 1;
 249                         break;
 250         }
 251         if ( p_ac3dec->ac3_decoder.b_invalid ) /* XXX */
 252         {
 253                 continue;
 254         }
 255
 256         parse_bsi( &p_ac3dec->ac3_decoder );
 257
 258         for (i = 0; i < 6; i++)
 259             {
 260             s16 * buffer;
 261
 262             buffer = ((ac3dec_frame_t *)p_ac3dec->p_aout_fifo->buffer)[ p_ac3dec->p_aout_fifo->l_end_frame ];
 263
 264             if (ac3_audio_block (&p_ac3dec->ac3_decoder, buffer))
 265                 goto bad_frame;
 266
 267             if (i)
 268                 p_ac3dec->p_aout_fifo->date[p_ac3dec->p_aout_fifo->l_end_frame] = LAST_MDATE;
 269             vlc_mutex_lock( &p_ac3dec->p_aout_fifo->data_lock );
 270             p_ac3dec->p_aout_fifo->l_end_frame = (p_ac3dec->p_aout_fifo->l_end_frame + 1) & AOUT_FIFO_SIZE;
 271             vlc_cond_signal( &p_ac3dec->p_aout_fifo->data_wait );
 272             vlc_mutex_unlock( &p_ac3dec->p_aout_fifo->data_lock );
 273         }
 274
 275         parse_auxdata( &p_ac3dec->ac3_decoder );
 276 bad_frame:
 277     }
 278
 279     /* If b_error is set, the ac3 decoder thread enters the error loop */
 280     if ( p_ac3dec->b_error )
 281     {
 282         ErrorThread( p_ac3dec );
 283     }
 284
 285     /* End of the ac3 decoder thread */
 286     EndThread( p_ac3dec );
 287 }
 288
 289 /*****************************************************************************
 290  * ErrorThread : ac3 decoder's RunThread() error loop
 291  *****************************************************************************/
 292 static void ErrorThread( ac3dec_thread_t * p_ac3dec )
 293 {
 294     /* We take the lock, because we are going to read/write the start/end
 295      * indexes of the decoder fifo */
 296     vlc_mutex_lock( &p_ac3dec->fifo.data_lock );
 297
 298     /* Wait until a `die' order is sent */
 299     while( !p_ac3dec->b_die )
 300     {
 301         /* Trash all received PES packets */
 302         while( !DECODER_FIFO_ISEMPTY(p_ac3dec->fifo) )
 303         {
 304             input_NetlistFreePES( p_ac3dec->ac3_decoder.bit_stream.p_input, DECODER_FIFO_START(p_ac3dec->fifo) );
 305             DECODER_FIFO_INCSTART( p_ac3dec->fifo );
 306         }
 307
 308         /* Waiting for the input thread to put new PES packets in the fifo */
 309         vlc_cond_wait( &p_ac3dec->fifo.data_wait, &p_ac3dec->fifo.data_lock );
 310     }
 311
 312     /* We can release the lock before leaving */
 313     vlc_mutex_unlock( &p_ac3dec->fifo.data_lock );
 314 }
 315
 316 /*****************************************************************************
 317  * EndThread : ac3 decoder thread destruction
 318  *****************************************************************************/
 319 static void EndThread( ac3dec_thread_t * p_ac3dec )
 320 {
 321     intf_DbgMsg( "ac3dec debug: destroying ac3 decoder thread %p\n", p_ac3dec );
 322
 323     /* If the audio output fifo was created, we destroy it */
 324     if ( p_ac3dec->p_aout_fifo != NULL )
 325     {
 326         aout_DestroyFifo( p_ac3dec->p_aout_fifo );
 327
 328         /* Make sure the output thread leaves the NextFrame() function */
 329         vlc_mutex_lock( &(p_ac3dec->p_aout_fifo->data_lock) );
 330         vlc_cond_signal( &(p_ac3dec->p_aout_fifo->data_wait) );
 331         vlc_mutex_unlock( &(p_ac3dec->p_aout_fifo->data_lock) );
 332     }
 333
 334     /* Destroy descriptor */
 335     free( p_ac3dec );
 336
 337     intf_DbgMsg( "ac3dec debug: ac3 decoder thread %p destroyed\n", p_ac3dec );
 338 }