1 /*****************************************************************************
2 * mpeg4audio.c: parse and packetize an MPEG 4 audio stream
3 *****************************************************************************
4 * Copyright (C) 2001, 2002 VideoLAN
5 * $Id: mpeg4audio.c,v 1.9 2003/10/05 18:09:36 gbazin Exp $
7 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
8 * Gildas Bazin <gbazin@netcourrier.com>
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 <stdlib.h> /* malloc(), free() */
29 #include <string.h> /* strdup() */
33 #include <vlc/decoder.h>
34 #include <vlc/input.h>
38 #include "vlc_block_helper.h"
42 * AudioObjectType 5 bits
43 * samplingFrequencyIndex 4 bits
44 * if (samplingFrequencyIndex == 0xF)
45 * samplingFrequency 24 bits
46 * channelConfiguration 4 bits
48 * FrameLengthFlag 1 bit 1024 or 960
49 * DependsOnCoreCoder 1 bit (always 0)
50 * ExtensionFlag 1 bit (always 0)
53 /*****************************************************************************
54 * decoder_sys_t : decoder descriptor
55 *****************************************************************************/
65 block_bytestream_t bytestream;
68 * Packetizer output properties
70 sout_packetizer_input_t *p_sout_input;
71 sout_format_t sout_format;
72 sout_buffer_t * p_sout_buffer; /* current sout buffer */
77 audio_date_t end_date;
80 int i_frame_size, i_raw_blocks;
81 unsigned int i_channels;
82 unsigned int i_rate, i_frame_length;
94 static int i_sample_rates[] =
96 96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050,
97 16000, 12000, 11025, 8000, 7350, 0, 0, 0
100 #define ADTS_HEADER_SIZE 6
102 /****************************************************************************
104 ****************************************************************************/
105 static int OpenPacketizer( vlc_object_t * );
106 static int InitPacketizer( decoder_t * );
107 static int RunFramePacketizer ( decoder_t *, block_t * );
108 static int RunADTSPacketizer ( decoder_t *, block_t * );
109 static int EndPacketizer ( decoder_t * );
110 static int GetSoutBuffer( decoder_t *, sout_buffer_t ** );
112 static int ADTSSyncInfo( decoder_t *, const byte_t * p_buf,
113 unsigned int * pi_channels,
114 unsigned int * pi_sample_rate,
115 unsigned int * pi_frame_length,
116 unsigned int * pi_raw_blocks );
118 /*****************************************************************************
120 *****************************************************************************/
122 set_description( _("MPEG4 Audio packetizer") );
123 set_capability( "packetizer", 50 );
124 set_callbacks( OpenPacketizer, NULL );
127 /*****************************************************************************
128 * OpenPacketizer: probe the packetizer and return score
129 *****************************************************************************/
130 static int OpenPacketizer( vlc_object_t *p_this )
132 decoder_t *p_dec = (decoder_t*)p_this;
134 if( p_dec->p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', '4', 'a' ) )
139 /* Allocate the memory needed to store the decoder's structure */
141 (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
143 msg_Err( p_dec, "out of memory" );
147 p_dec->pf_init = InitPacketizer;
148 p_dec->pf_decode = RunFramePacketizer;
149 p_dec->pf_end = EndPacketizer;
154 /*****************************************************************************
155 * InitPacketizer: Initalize the packetizer
156 *****************************************************************************/
157 static int InitPacketizer( decoder_t *p_dec )
159 decoder_sys_t *p_sys = p_dec->p_sys;
162 p_sys->i_state = STATE_NOSYNC;
163 p_sys->b_synchro = VLC_FALSE;
165 aout_DateSet( &p_sys->end_date, 0 );
167 p_sys->p_sout_input = NULL;
168 p_sys->p_sout_buffer = NULL;
169 p_sys->p_chain = NULL;
171 msg_Info( p_dec, "Running MPEG4 audio packetizer" );
173 p_wf = (WAVEFORMATEX*)p_dec->p_fifo->p_waveformatex;
175 if( p_wf && p_wf->cbSize > 0)
177 uint8_t *p_config = (uint8_t*)&p_wf[1];
180 i_index = ( ( p_config[0] << 1 ) | ( p_config[1] >> 7 ) ) & 0x0f;
181 if( i_index != 0x0f )
183 p_sys->i_rate = i_sample_rates[i_index];
184 p_sys->i_frame_length = (( p_config[1] >> 2 ) & 0x01) ? 960 : 1024;
188 p_sys->i_rate = ( ( p_config[1] & 0x7f ) << 17 ) |
189 ( p_config[2] << 9 ) | ( p_config[3] << 1 ) |
190 ( p_config[4] >> 7 );
191 p_sys->i_frame_length = (( p_config[4] >> 2 ) & 0x01) ? 960 : 1024;
194 msg_Dbg( p_dec, "AAC %dHz %d samples/frame",
195 p_sys->i_rate, p_sys->i_frame_length );
197 p_sys->i_channels = p_wf->nChannels;
198 p_sys->sout_format.i_extra_data = p_wf->cbSize;
199 p_sys->sout_format.p_extra_data = malloc( p_wf->cbSize );
200 memcpy( p_sys->sout_format.p_extra_data, &p_wf[1], p_wf->cbSize );
204 msg_Dbg( p_dec, "No decoder specific info, must be an ADTS stream" );
206 /* We will try to create a AAC Config from adts */
207 p_sys->sout_format.i_extra_data = 0;
208 p_sys->sout_format.p_extra_data = NULL;
209 p_dec->pf_decode = RunADTSPacketizer;
215 /****************************************************************************
216 * RunFramePacketizer: the whole thing
217 ****************************************************************************
218 * This function must be fed with complete frames.
219 ****************************************************************************/
220 static int RunFramePacketizer( decoder_t *p_dec, block_t *p_block )
222 decoder_sys_t *p_sys = p_dec->p_sys;
224 if( !aout_DateGet( &p_sys->end_date ) && !p_block->i_pts )
226 /* We've just started the stream, wait for the first PTS. */
227 block_Release( p_block );
231 p_sys->pts = p_block->i_pts;
232 p_sys->i_frame_size = p_block->i_buffer;
234 if( GetSoutBuffer( p_dec, &p_sys->p_sout_buffer ) != VLC_SUCCESS )
239 /* Copy the whole frame into the buffer */
240 p_dec->p_vlc->pf_memcpy( p_sys->p_sout_buffer->p_buffer,
241 p_block->p_buffer, p_block->i_buffer );
243 sout_InputSendBuffer( p_sys->p_sout_input, p_sys->p_sout_buffer );
244 p_sys->p_sout_buffer = NULL;
246 block_Release( p_block );
250 /****************************************************************************
251 * RunADTSPacketizer: the whole thing
252 ****************************************************************************/
253 static int RunADTSPacketizer( decoder_t *p_dec, block_t *p_block )
255 decoder_sys_t *p_sys = p_dec->p_sys;
256 uint8_t p_header[ADTS_HEADER_SIZE];
258 if( (!aout_DateGet( &p_sys->end_date ) && !p_block->i_pts)
259 || p_block->b_discontinuity )
261 /* We've just started the stream, wait for the first PTS. */
262 block_Release( p_block );
263 p_sys->b_synchro = VLC_FALSE;
269 block_ChainAppend( &p_sys->p_chain, p_block );
273 block_ChainAppend( &p_sys->p_chain, p_block );
274 p_sys->bytestream = block_BytestreamInit( p_dec, p_sys->p_chain, 0 );
279 switch( p_sys->i_state )
283 while( block_PeekBytes( &p_sys->bytestream, p_header, 2 )
286 /* Look for sync word - should be 0xfff + 2 layer bits */
287 if( p_header[0] == 0xff && (p_header[1] & 0xf6) == 0xf0 )
289 p_sys->i_state = STATE_SYNC;
292 block_SkipByte( &p_sys->bytestream );
293 p_sys->b_synchro = VLC_FALSE;
295 if( p_sys->i_state != STATE_SYNC )
297 block_ChainRelease( p_sys->p_chain );
298 p_sys->p_chain = NULL;
305 /* New frame, set the Presentation Time Stamp */
306 p_sys->pts = p_sys->bytestream.p_block->i_pts;
307 if( p_sys->pts != 0 &&
308 p_sys->pts != aout_DateGet( &p_sys->end_date ) )
310 aout_DateSet( &p_sys->end_date, p_sys->pts );
312 p_sys->i_state = STATE_HEADER;
316 /* Get ADTS frame header (ADTS_HEADER_SIZE bytes) */
317 if( block_PeekBytes( &p_sys->bytestream, p_header,
318 ADTS_HEADER_SIZE ) != VLC_SUCCESS )
324 /* Check if frame is valid and get frame info */
325 p_sys->i_frame_size = ADTSSyncInfo( p_dec, p_header,
328 &p_sys->i_frame_length,
329 &p_sys->i_raw_blocks );
330 if( !p_sys->i_frame_size )
332 msg_Dbg( p_dec, "emulated sync word" );
333 block_SkipByte( &p_sys->bytestream );
334 p_sys->i_state = STATE_NOSYNC;
335 p_sys->b_synchro = VLC_FALSE;
339 p_sys->i_state = STATE_DATA;
342 /* TODO: If p_block == NULL, flush the buffer without checking the
345 if( !p_sys->b_synchro )
347 /* Check if next expected frame contains the sync word */
348 if( block_PeekOffsetBytes( &p_sys->bytestream,
349 p_sys->i_frame_size, p_header, 2 )
356 if( p_header[0] != 0xff || (p_header[1] & 0xf6) != 0xf0 )
358 msg_Dbg( p_dec, "emulated sync word "
359 "(no sync on following frame)" );
360 p_sys->i_state = STATE_NOSYNC;
361 block_SkipByte( &p_sys->bytestream );
362 p_sys->b_synchro = VLC_FALSE;
367 if( !p_sys->p_sout_buffer )
368 if( GetSoutBuffer( p_dec, &p_sys->p_sout_buffer ) != VLC_SUCCESS )
373 /* Copy the whole frame into the buffer */
374 if( block_GetBytes( &p_sys->bytestream,
375 p_sys->p_sout_buffer->p_buffer,
376 p_sys->i_frame_size ) != VLC_SUCCESS )
382 p_sys->p_chain = block_BytestreamFlush( &p_sys->bytestream );
384 sout_InputSendBuffer( p_sys->p_sout_input, p_sys->p_sout_buffer );
386 p_sys->i_state = STATE_NOSYNC;
387 p_sys->p_sout_buffer = NULL;
388 p_sys->b_synchro = VLC_TRUE;
390 /* Make sure we don't reuse the same pts twice */
391 if( p_sys->pts == p_sys->bytestream.p_block->i_pts )
392 p_sys->pts = p_sys->bytestream.p_block->i_pts = 0;
399 /*****************************************************************************
401 *****************************************************************************/
402 static int GetSoutBuffer( decoder_t *p_dec, sout_buffer_t **pp_buffer )
404 decoder_sys_t *p_sys = p_dec->p_sys;
406 if( p_sys->p_sout_input != NULL &&
407 ( p_sys->sout_format.i_sample_rate != (int)p_sys->i_rate
408 || p_sys->sout_format.i_channels != (int)p_sys->i_channels ) )
410 /* Parameters changed - this should not happen. */
413 /* Creating the sout input if not created yet. */
414 if( p_sys->p_sout_input == NULL )
416 p_sys->sout_format.i_cat = AUDIO_ES;
417 p_sys->sout_format.i_fourcc = VLC_FOURCC( 'm', 'p', '4', 'a' );
418 p_sys->sout_format.i_sample_rate = p_sys->i_rate;
419 p_sys->sout_format.i_channels = p_sys->i_channels;
420 p_sys->sout_format.i_block_align = 0;
421 p_sys->sout_format.i_bitrate = 0;
423 aout_DateInit( &p_sys->end_date, p_sys->i_rate );
424 aout_DateSet( &p_sys->end_date, p_sys->pts );
426 p_sys->p_sout_input = sout_InputNew( p_dec, &p_sys->sout_format );
427 if( p_sys->p_sout_input == NULL )
429 msg_Err( p_dec, "cannot add a new stream" );
433 msg_Info( p_dec, "AAC channels: %d samplerate: %d",
434 p_sys->i_channels, p_sys->i_rate );
437 *pp_buffer = sout_BufferNew( p_sys->p_sout_input->p_sout,
438 p_sys->i_frame_size );
439 if( *pp_buffer == NULL )
444 (*pp_buffer)->i_pts =
445 (*pp_buffer)->i_dts = aout_DateGet( &p_sys->end_date );
447 (*pp_buffer)->i_length =
448 aout_DateIncrement( &p_sys->end_date, p_sys->i_frame_length )
449 - (*pp_buffer)->i_pts;
454 /*****************************************************************************
455 * EndPacketizer: clean up the packetizer
456 *****************************************************************************/
457 static int EndPacketizer( decoder_t *p_dec )
459 if( p_dec->p_sys->p_sout_input != NULL )
461 if( p_dec->p_sys->p_sout_buffer )
463 sout_BufferDelete( p_dec->p_sys->p_sout_input->p_sout,
464 p_dec->p_sys->p_sout_buffer );
467 sout_InputDelete( p_dec->p_sys->p_sout_input );
470 if( p_dec->p_sys->p_chain ) block_ChainRelease( p_dec->p_sys->p_chain );
472 free( p_dec->p_sys );
477 /*****************************************************************************
478 * ADTSSyncInfo: parse MPEG 4 audio ADTS sync info
479 *****************************************************************************/
480 static int ADTSSyncInfo( decoder_t * p_dec, const byte_t * p_buf,
481 unsigned int * pi_channels,
482 unsigned int * pi_sample_rate,
483 unsigned int * pi_frame_length,
484 unsigned int * pi_raw_blocks_in_frame )
486 decoder_sys_t *p_sys = p_dec->p_sys;
487 int i_id, i_profile, i_sample_rate_idx, i_frame_size;
489 /* Fixed header between frames */
490 i_id = ( (p_buf[1] >> 3) & 0x01 ) ? 2 : 4;
491 i_profile = p_buf[2] >> 6;
492 i_sample_rate_idx = (p_buf[2] >> 2) & 0x0f;
493 *pi_sample_rate = i_sample_rates[i_sample_rate_idx];
494 *pi_channels = ((p_buf[2] & 0x01) << 2) | ((p_buf[3] >> 6) & 0x03);
496 /* Variable header */
497 i_frame_size = ((p_buf[3] & 0x03) << 11) | (p_buf[4] << 3) |
498 ((p_buf[5] >> 5) & 0x7);
499 *pi_raw_blocks_in_frame = (p_buf[6] & 0x02) + 1;
501 if( !*pi_sample_rate || !*pi_channels || !i_frame_size )
507 *pi_frame_length = 1024;
509 /* Build the decoder specific info header */
510 if( !p_dec->p_sys->sout_format.i_extra_data )
512 p_sys->sout_format.i_extra_data = 2;
513 p_sys->sout_format.p_extra_data = malloc( 2 );
514 p_sys->sout_format.p_extra_data[0] =
515 (i_profile + 1) << 3 | (i_sample_rate_idx > 1);
516 p_sys->sout_format.p_extra_data[1] =
517 ((i_sample_rate_idx & 0x01) << 7) | (*pi_channels <<3);