1 /*****************************************************************************
2 * aout_pcm.c: PCM audio output functions
3 *****************************************************************************
4 * Copyright (C) 1999-2002 VideoLAN
5 * $Id: aout_pcm.c,v 1.6 2002/05/18 17:47:47 sam Exp $
7 * Authors: Michel Kaempf <maxx@via.ecp.fr>
8 * Cyril Deguet <asmax@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
25 /*****************************************************************************
27 *****************************************************************************/
28 #include <stdio.h> /* "intf_msg.h" */
29 #include <stdlib.h> /* calloc(), malloc(), free() */
32 #include <videolan/vlc.h>
34 #include "audio_output.h"
37 /* Biggest difference allowed between scheduled playing date and actual date
39 #define MAX_DELTA 10000
41 /*****************************************************************************
43 *****************************************************************************/
44 static void FillBuffer( aout_thread_t * p_aout, aout_fifo_t * p_fifo );
45 static int NextFrame ( aout_thread_t * p_aout, aout_fifo_t * p_fifo,
48 /*****************************************************************************
50 *****************************************************************************/
51 void aout_PCMThread( aout_thread_t * p_aout )
54 int i_buffer, i_buffer_limit, i_units = 0;
57 if( !SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_ABOVE_NORMAL) )
58 intf_WarnMsg( 2, "aout warning: couldn't change priority of"
62 /* As the s32_buffer was created with calloc(), we don't have to set this
63 * memory to zero and we can immediately jump into the thread's loop */
64 while ( ! p_aout->b_die )
66 vlc_mutex_lock( &p_aout->fifos_lock );
67 for ( i_fifo = 0; i_fifo < AOUT_MAX_FIFOS; i_fifo++ )
69 if( p_aout->fifo[i_fifo].b_die )
71 aout_FreeFifo( &p_aout->fifo[i_fifo] );
75 FillBuffer( p_aout, &p_aout->fifo[i_fifo] );
78 vlc_mutex_unlock( &p_aout->fifos_lock );
80 i_buffer_limit = p_aout->i_units * p_aout->i_channels;
82 switch ( p_aout->i_format )
85 for ( i_buffer = 0; i_buffer < i_buffer_limit; i_buffer++ )
87 ((u8*)p_aout->buffer)[i_buffer] = (u8)(
88 (p_aout->s32_buffer[i_buffer] / AOUT_MAX_FIFOS / 256 + 128)
89 * p_aout->i_volume / 256);
90 p_aout->s32_buffer[i_buffer] = 0;
95 for ( i_buffer = 0; i_buffer < i_buffer_limit; i_buffer++ )
97 ((s8*)p_aout->buffer)[i_buffer] = (s8)(
98 p_aout->s32_buffer[i_buffer] / AOUT_MAX_FIFOS / 256
99 * p_aout->i_volume / 256);
100 p_aout->s32_buffer[i_buffer] = 0;
104 case AOUT_FMT_U16_LE:
105 case AOUT_FMT_U16_BE:
106 for ( i_buffer = 0; i_buffer < i_buffer_limit; i_buffer++ )
108 ((u16*)p_aout->buffer)[i_buffer] = (u16)(
109 (p_aout->s32_buffer[i_buffer] / AOUT_MAX_FIFOS + 128)
110 * p_aout->i_volume / 256);
111 p_aout->s32_buffer[i_buffer] = 0;
115 case AOUT_FMT_S16_LE:
116 case AOUT_FMT_S16_BE:
117 for ( i_buffer = 0; i_buffer < i_buffer_limit; i_buffer++ )
119 ((s16*)p_aout->buffer)[i_buffer] = (s16)(
120 p_aout->s32_buffer[i_buffer] / AOUT_MAX_FIFOS
121 * p_aout->i_volume / 256);
122 p_aout->s32_buffer[i_buffer] = 0;
127 switch ( p_aout->i_format )
131 i_units = p_aout->pf_getbufinfo( p_aout, i_buffer_limit );
133 p_aout->date = mdate() + ((((mtime_t)((i_units + 4 *
134 p_aout->i_latency) / p_aout->i_channels)) * 1000000) /
135 ((mtime_t)p_aout->i_rate)) + p_main->i_desync;
137 p_aout->pf_play( p_aout, (byte_t *)p_aout->buffer,
141 case AOUT_FMT_U16_LE:
142 case AOUT_FMT_U16_BE:
143 case AOUT_FMT_S16_LE:
144 case AOUT_FMT_S16_BE:
145 i_units = p_aout->pf_getbufinfo( p_aout, i_buffer_limit * 2 ) / 2;
147 p_aout->date = mdate() + ((((mtime_t)((i_units + 4 *
148 p_aout->i_latency) / (2 * p_aout->i_channels))) * 1000000) /
149 ((mtime_t)p_aout->i_rate)) + p_main->i_desync;
151 p_aout->pf_play( p_aout, (byte_t *)p_aout->buffer,
152 i_buffer_limit * 2 );
156 /* Sleep until there is only AOUT_BUFFER_DURATION/2 worth of audio
157 * left to play in the aout plugin, then we can start refill the
159 if( i_units > (i_buffer_limit/2) )
160 msleep( (i_units - i_buffer_limit/2) * AOUT_BUFFER_DURATION
165 vlc_mutex_lock( &p_aout->fifos_lock );
166 for ( i_fifo = 0; i_fifo < AOUT_MAX_FIFOS; i_fifo++ )
168 aout_FreeFifo( &p_aout->fifo[i_fifo] );
170 vlc_mutex_unlock( &p_aout->fifos_lock );
173 /* Following functions are local */
175 /*****************************************************************************
176 * InitializeIncrement: change i_x/i_y to i_a+i_b/i_c
177 *****************************************************************************/
178 static inline void InitializeIncrement( aout_increment_t * p_inc,
194 /*****************************************************************************
196 *****************************************************************************/
197 static inline void UpdateIncrement( aout_increment_t * p_inc, int * pi_integer )
199 if( (p_inc->i_r += p_inc->i_b) >= 0 )
201 *pi_integer += p_inc->i_a + 1;
202 p_inc->i_r -= p_inc->i_c;
206 *pi_integer += p_inc->i_a;
210 /*****************************************************************************
211 * FillBuffer: Read data from decoder fifo, and put it in S32_buffer
212 *****************************************************************************/
213 static void FillBuffer( aout_thread_t * p_aout, aout_fifo_t * p_fifo )
216 int i_buffer_limit, i_units;
218 switch ( p_fifo->i_format )
222 i_units = p_aout->i_units;
224 /* While there are empty frames in the buffer, fill them */
225 while ( i_units > 0 )
227 /* If there is no next frame, wait for one */
228 if( !p_fifo->b_next_frame )
230 if( NextFrame(p_aout, p_fifo, p_aout->date +
231 ((((mtime_t)(i_buffer >> 1)) * 1000000) /
232 ((mtime_t)p_aout->i_rate))) )
238 i_buffer_limit = p_aout->i_units * p_aout->i_channels;
240 while ( i_buffer < i_buffer_limit )
242 /* FIXME: make this more generic */
243 if( p_aout->i_channels == 2 )
245 p_aout->s32_buffer[i_buffer++] +=
246 (s32)( ((s16 *)p_fifo->buffer)[2*p_fifo->i_unit] );
247 p_aout->s32_buffer[i_buffer++] +=
248 (s32)( ((s16 *)p_fifo->buffer)[2*p_fifo->i_unit+1] );
250 else if( p_aout->i_channels == 1 )
252 p_aout->s32_buffer[i_buffer++] +=
253 (s32)( ((s16 *)p_fifo->buffer)[p_fifo->i_unit] );
257 intf_ErrMsg( "aout error: unsupported number of channels" );
260 UpdateIncrement(&p_fifo->unit_increment, &p_fifo->i_unit);
262 if( p_fifo->i_unit >= p_fifo->i_unit_limit )
264 p_fifo->i_unit -= p_fifo->i_unit_limit;
268 if( p_fifo->i_units > i_units )
270 p_fifo->i_units -= i_units;
275 i_units -= p_fifo->i_units;
277 vlc_mutex_lock( &p_fifo->data_lock );
278 p_fifo->i_start_frame = p_fifo->i_next_frame;
279 /* p_fifo->b_start_frame = 1; */
280 p_fifo->i_next_frame = AOUT_FIFO_INC( p_fifo->i_next_frame );
281 p_fifo->b_next_frame = 0;
282 vlc_cond_signal( &p_fifo->data_wait );
283 vlc_mutex_unlock( &p_fifo->data_lock );
294 static int NextFrame( aout_thread_t * p_aout, aout_fifo_t * p_fifo,
297 int i_units, i_units_dist, i_rate;
300 /* We take the lock */
301 vlc_mutex_lock( &p_fifo->data_lock );
304 vlc_mutex_unlock( &p_fifo->data_lock );
308 /* Are we looking for a dated start frame ? */
309 if ( !p_fifo->b_start_frame )
311 while ( p_fifo->i_start_frame != p_fifo->i_end_frame )
313 if ( p_fifo->date[p_fifo->i_start_frame] != LAST_MDATE )
315 p_fifo->b_start_frame = 1;
316 p_fifo->i_next_frame = AOUT_FIFO_INC( p_fifo->i_start_frame );
317 p_fifo->i_unit = p_fifo->i_start_frame *
318 (p_fifo->i_frame_size / p_fifo->i_channels);
321 p_fifo->i_start_frame = AOUT_FIFO_INC( p_fifo->i_start_frame );
324 if ( p_fifo->i_start_frame == p_fifo->i_end_frame )
326 vlc_mutex_unlock( &p_fifo->data_lock );
331 /* We are looking for the next dated frame */
332 /* FIXME : is the output fifo full ?? -- pretty unlikely given its size */
333 while ( !p_fifo->b_next_frame )
335 while ( p_fifo->i_next_frame != p_fifo->i_end_frame )
337 if ( p_fifo->date[p_fifo->i_next_frame] != LAST_MDATE )
339 p_fifo->b_next_frame = 1;
342 p_fifo->i_next_frame = AOUT_FIFO_INC( p_fifo->i_next_frame );
345 while ( p_fifo->i_next_frame == p_fifo->i_end_frame )
347 vlc_cond_wait( &p_fifo->data_wait, &p_fifo->data_lock );
350 vlc_mutex_unlock( &p_fifo->data_lock );
356 i_units = ((p_fifo->i_next_frame - p_fifo->i_start_frame) & AOUT_FIFO_SIZE)
357 * (p_fifo->i_frame_size / p_fifo->i_channels);
359 i_delta = aout_date - p_fifo->date[p_fifo->i_start_frame];
361 /* Resample if delta is too long */
362 if( abs(i_delta) > MAX_DELTA )
364 i_rate = p_fifo->i_rate + (i_delta / 256);
368 i_rate = p_fifo->i_rate;
371 InitializeIncrement( &p_fifo->unit_increment, i_rate, p_aout->i_rate );
373 /* Calculate how many units we're going to write */
374 i_units_dist = p_fifo->i_unit - p_fifo->i_start_frame
375 * (p_fifo->i_frame_size / p_fifo->i_channels);
377 /* Manage the fifo wrapping */
378 if( i_units_dist > p_fifo->i_unit_limit / 2 )
380 i_units -= (i_units_dist - p_fifo->i_unit_limit);
382 else if( i_units_dist < - p_fifo->i_unit_limit / 2 )
384 i_units -= (i_units_dist + p_fifo->i_unit_limit);
388 i_units -= i_units_dist;
391 p_fifo->i_units = 1 + ( i_units * p_aout->i_rate / i_rate );
393 /* We release the lock before leaving */
394 vlc_mutex_unlock( &p_fifo->data_lock );