/*****************************************************************************
- * a52.c: ATSC A/52 aka AC-3 decoder plugin for vlc.
- * This plugin makes use of liba52 to decode A/52 audio
- * (http://liba52.sf.net/).
+ * a52.c: A/52 basic parser
*****************************************************************************
- * Copyright (C) 2001, 2002 VideoLAN
- * $Id: a52.c,v 1.8 2002/08/30 22:22:24 massiot Exp $
+ * Copyright (C) 2001-2002 VideoLAN
+ * $Id: a52.c,v 1.9 2002/09/02 23:17:05 massiot Exp $
*
- * Authors: Gildas Bazin <gbazin@netcourrier.com>
+ * Authors: Stéphane Borel <stef@via.ecp.fr>
* Christophe Massiot <massiot@via.ecp.fr>
- *
+ * Michel Lespinasse <walken@zoy.org>
+ * Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
/*****************************************************************************
* Preamble
*****************************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h> /* memcpy() */
+#include <fcntl.h>
+
#include <vlc/vlc.h>
-#include <vlc/aout.h>
#include <vlc/decoder.h>
-
-#include <stdlib.h> /* malloc(), free() */
-#include <string.h> /* strdup() */
-#ifdef HAVE_STDINT_H
-# include <stdint.h> /* int16_t .. */
-#elif HAVE_INTTYPES_H
-# include <inttypes.h> /* int16_t .. */
-#endif
+#include <vlc/aout.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
-#ifdef USE_A52DEC_TREE /* liba52 header file */
-# include "include/a52.h"
-#else
-# include "a52dec/a52.h"
-#endif
-
#define A52_FRAME_NB 1536
/*****************************************************************************
- * a52_thread_t : a52 decoder thread descriptor
+ * spdif_thread_t : A52 pass-through thread descriptor
*****************************************************************************/
-typedef struct a52_thread_s
+typedef struct spdif_thread_s
{
/*
- * liba52 properties
+ * Thread properties
*/
- a52_state_t * p_a52_state;
- vlc_bool_t b_dynrng;
-
- /* The bit stream structure handles the PES stream at the bit level */
- bit_stream_t bit_stream;
+ vlc_thread_t thread_id; /* id for thread functions */
/*
* Input properties
*/
decoder_fifo_t * p_fifo; /* stores the PES stream data */
- data_packet_t * p_data;
+
+ /* The bit stream structure handles the PES stream at the bit level */
+ bit_stream_t bit_stream;
/*
* Output properties
aout_instance_t * p_aout; /* opaque */
aout_input_t * p_aout_input; /* opaque */
audio_sample_format_t output_format;
- audio_date_t end_date;
-} a52_thread_t;
+} spdif_thread_t;
-/*****************************************************************************
+/****************************************************************************
* Local prototypes
- *****************************************************************************/
+ ****************************************************************************/
static int OpenDecoder ( vlc_object_t * );
static int RunDecoder ( decoder_fifo_t * );
-static int DecodeFrame ( a52_thread_t *, byte_t * );
-static int InitThread ( a52_thread_t *, decoder_fifo_t * );
-static void EndThread ( a52_thread_t * );
+
+static int InitThread ( spdif_thread_t *, decoder_fifo_t * );
+static void EndThread ( spdif_thread_t * );
+
+static int SyncInfo ( const byte_t *, int *, int *, int * );
/*****************************************************************************
* Module descriptor
*****************************************************************************/
-#define DYNRNG_TEXT N_("A/52 dynamic range compression")
-#define DYNRNG_LONGTEXT N_( \
- "Dynamic range compression makes the loud sounds softer, and the soft " \
- "sounds louder, so you can more easily listen to the stream in a noisy " \
- "environment without disturbing anyone. If you disable the dynamic range "\
- "compression the playback will be more adapted to a movie theater or a " \
- "listening room.")
-
vlc_module_begin();
- add_category_hint( N_("Miscellaneous"), NULL );
- add_bool( "a52-dynrng", 1, NULL, DYNRNG_TEXT, DYNRNG_LONGTEXT );
- set_description( _("a52 ATSC A/52 aka AC-3 audio decoder module") );
- set_capability( "decoder", 60 );
+ set_description( _("A/52 parser") );
+ set_capability( "decoder", 0 );
set_callbacks( OpenDecoder, NULL );
+ add_shortcut( "pass_through" );
+ add_shortcut( "pass" );
vlc_module_end();
/*****************************************************************************
* OpenDecoder: probe the decoder and return score
*****************************************************************************
- * Tries to launch a decoder and return score so that the interface is able
- * to choose.
+ * Tries to launch a decoder and return score so that the interface is able
+ * to chose.
*****************************************************************************/
-static int OpenDecoder( vlc_object_t *p_this )
-{
+static int OpenDecoder( vlc_object_t *p_this )
+{
decoder_fifo_t *p_fifo = (decoder_fifo_t*) p_this;
-
+
if( p_fifo->i_fourcc != VLC_FOURCC('a','5','2',' ')
&& p_fifo->i_fourcc != VLC_FOURCC('a','5','2','b') )
{
- return VLC_EGENERIC;
+ return VLC_EGENERIC;
}
p_fifo->pf_run = RunDecoder;
return VLC_SUCCESS;
}
-/*****************************************************************************
- * RunDecoder: this function is called just after the thread is created
- *****************************************************************************/
+/****************************************************************************
+ * RunDecoder: the whole thing
+ ****************************************************************************
+ * This function is called just after the thread is launched.
+ ****************************************************************************/
static int RunDecoder( decoder_fifo_t *p_fifo )
{
- a52_thread_t *p_dec;
-
+ spdif_thread_t * p_dec;
+ audio_date_t end_date;
+
/* Allocate the memory needed to store the thread's structure */
- p_dec = (a52_thread_t *)malloc( sizeof(a52_thread_t) );
+ p_dec = malloc( sizeof(spdif_thread_t) );
if( p_dec == NULL )
{
msg_Err( p_fifo, "out of memory" );
DecoderError( p_fifo );
return -1;
}
-
- if( InitThread( p_dec, p_fifo ) )
+
+ if ( InitThread( p_dec, p_fifo ) )
{
- msg_Err( p_dec->p_fifo, "could not initialize thread" );
+
+ msg_Err( p_fifo, "could not initialize thread" );
DecoderError( p_fifo );
free( p_dec );
return -1;
}
- /* liba52 decoder thread's main loop */
- while( !p_dec->p_fifo->b_die && !p_dec->p_fifo->b_error )
+ /* decoder thread's main loop */
+ while ( !p_dec->p_fifo->b_die && !p_dec->p_fifo->b_error )
{
- int i_frame_size, i_flags, i_rate, i_bit_rate;
+ int i_frame_size, i_channels, i_rate, i_bit_rate;
mtime_t pts;
/* Temporary buffer to store the raw frame to be decoded */
- byte_t p_frame_buffer[3840];
+ byte_t p_header[7];
+ aout_buffer_t * p_buffer;
/* Look for sync word - should be 0x0b77 */
RealignBits( &p_dec->bit_stream );
- while( (ShowBits( &p_dec->bit_stream, 16 ) ) != 0x0b77 &&
- (!p_dec->p_fifo->b_die) && (!p_dec->p_fifo->b_error))
+ while ( (ShowBits( &p_dec->bit_stream, 16 ) ) != 0x0b77 &&
+ (!p_dec->p_fifo->b_die) && (!p_dec->p_fifo->b_error))
{
RemoveBits( &p_dec->bit_stream, 8 );
}
/* Set the Presentation Time Stamp */
NextPTS( &p_dec->bit_stream, &pts, NULL );
- if ( pts != 0 && pts != aout_DateGet( &p_dec->end_date ) )
+ if ( pts != 0 && pts != aout_DateGet( &end_date ) )
{
- aout_DateSet( &p_dec->end_date, pts );
+ aout_DateSet( &end_date, pts );
}
/* Get A/52 frame header */
- GetChunk( &p_dec->bit_stream, p_frame_buffer, 7 );
+ GetChunk( &p_dec->bit_stream, p_header, 7 );
if( p_dec->p_fifo->b_die ) break;
/* Check if frame is valid and get frame info */
- i_frame_size = a52_syncinfo( p_frame_buffer, &i_flags, &i_rate,
- &i_bit_rate );
+ i_frame_size = SyncInfo( p_header, &i_channels, &i_rate,
+ &i_bit_rate );
if( !i_frame_size )
{
if( (p_dec->p_aout_input != NULL) &&
( (p_dec->output_format.i_rate != i_rate)
- /* || (p_dec->output_format.i_channels != i_channels) */ ) )
+ || (p_dec->output_format.i_channels != i_channels)
+ || (p_dec->output_format.i_bytes_per_frame != i_frame_size) ) )
{
/* Parameters changed - this should not happen. */
aout_InputDelete( p_dec->p_aout, p_dec->p_aout_input );
if( p_dec->p_aout_input == NULL )
{
p_dec->output_format.i_rate = i_rate;
- /* p_dec->output_format.i_channels = i_channels; */
- aout_DateInit( &p_dec->end_date, i_rate );
+ p_dec->output_format.i_channels = i_channels;
+ p_dec->output_format.i_bytes_per_frame = i_frame_size;
+ p_dec->output_format.i_frame_length = A52_FRAME_NB;
+ aout_DateInit( &end_date, i_rate );
p_dec->p_aout_input = aout_InputNew( p_dec->p_fifo,
&p_dec->p_aout,
&p_dec->output_format );
}
}
- /* Get the complete frame */
- GetChunk( &p_dec->bit_stream, p_frame_buffer + 7,
+ if ( !aout_DateGet( &end_date ) )
+ {
+ byte_t p_junk[3840];
+
+ /* We've just started the stream, wait for the first PTS. */
+ GetChunk( &p_dec->bit_stream, p_junk, i_frame_size - 7 );
+ continue;
+ }
+
+ p_buffer = aout_BufferNew( p_dec->p_aout, p_dec->p_aout_input,
+ A52_FRAME_NB );
+ if ( p_buffer == NULL ) return -1;
+ p_buffer->start_date = aout_DateGet( &end_date );
+ p_buffer->end_date = aout_DateIncrement( &end_date,
+ A52_FRAME_NB );
+
+ /* Get the whole frame. */
+ memcpy( p_buffer->p_buffer, p_header, 7 );
+ GetChunk( &p_dec->bit_stream, p_buffer->p_buffer + 7,
i_frame_size - 7 );
if( p_dec->p_fifo->b_die ) break;
- if( DecodeFrame( p_dec, p_frame_buffer ) )
- {
- p_dec->p_fifo->b_error = 1;
- break;
- }
+ /* Send the buffer to the mixer. */
+ aout_BufferPlay( p_dec->p_aout, p_dec->p_aout_input, p_buffer );
}
- /* If b_error is set, the decoder thread enters the error loop */
+ /* If b_error is set, the spdif thread enters the error loop */
if( p_dec->p_fifo->b_error )
{
DecoderError( p_dec->p_fifo );
}
- /* End of the a52 decoder thread */
+ /* End of the spdif decoder thread */
EndThread( p_dec );
-
+
return 0;
}
-/*****************************************************************************
- * InitThread: initialize data before entering main loop
- *****************************************************************************/
-static int InitThread( a52_thread_t * p_dec, decoder_fifo_t * p_fifo )
+/****************************************************************************
+ * InitThread: initialize thread data and create output fifo
+ ****************************************************************************/
+static int InitThread( spdif_thread_t * p_dec, decoder_fifo_t * p_fifo )
{
/* Initialize the thread properties */
p_dec->p_aout = NULL;
p_dec->p_aout_input = NULL;
p_dec->p_fifo = p_fifo;
- p_dec->output_format.i_format = AOUT_FMT_FLOAT32;
- p_dec->output_format.i_channels = 2; /* FIXME ! */
-
- /* Initialize liba52 */
- p_dec->p_a52_state = a52_init( 0 );
- if( p_dec->p_a52_state == NULL )
- {
- msg_Err( p_dec->p_fifo, "unable to initialize liba52" );
- return -1;
- }
-
- p_dec->b_dynrng = config_GetInt( p_dec->p_fifo, "a52-dynrng" );
+ p_dec->output_format.i_format = AOUT_FMT_A52;
/* Init the Bitstream */
InitBitstream( &p_dec->bit_stream, p_dec->p_fifo,
}
/*****************************************************************************
- * Interleave: helper function to interleave channels
+ * EndThread : spdif thread destruction
*****************************************************************************/
-static void Interleave( float * p_out, const float * p_in, int i_channels )
+static void EndThread( spdif_thread_t * p_dec )
{
- int i, j;
-
- for ( j = 0; j < i_channels; j++ )
+ if ( p_dec->p_aout_input != NULL )
{
- for ( i = 0; i < 256; i++ )
- {
- p_out[i * i_channels + j] = p_in[j * 256 + i];
- }
+ aout_InputDelete( p_dec->p_aout, p_dec->p_aout_input );
}
+
+ free( p_dec );
}
-/*****************************************************************************
- * DecodeFrame: decode an ATSC A/52 frame.
- *****************************************************************************/
-static int DecodeFrame( a52_thread_t * p_dec, byte_t * p_frame_buffer )
+/****************************************************************************
+ * SyncInfo: parse A52 sync info
+ ****************************************************************************
+ * This code is borrowed from liba52 by Aaron Holtzman & Michel Lespinasse,
+ * since we don't want to oblige S/PDIF people to use liba52 just to get
+ * their SyncInfo...
+ ****************************************************************************/
+int SyncInfo( const byte_t * p_buf, int * pi_channels, int * pi_sample_rate,
+ int * pi_bit_rate)
{
- sample_t i_sample_level = 1;
- aout_buffer_t * p_buffer;
- int i, i_flags;
- int i_bytes_per_block = 256 * p_dec->output_format.i_channels
- * sizeof(float);
-
- if( !aout_DateGet( &p_dec->end_date ) )
- {
- /* We've just started the stream, wait for the first PTS. */
+ static const u8 halfrate[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3};
+ static const int rate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
+ 128, 160, 192, 224, 256, 320, 384, 448,
+ 512, 576, 640};
+ static const u8 lfeon[8] = {0x10, 0x10, 0x04, 0x04, 0x04, 0x01, 0x04, 0x01};
+ int frmsizecod;
+ int bitrate;
+ int half;
+ int acmod;
+
+ if ((p_buf[0] != 0x0b) || (p_buf[1] != 0x77)) /* syncword */
return 0;
- }
-
- p_buffer = aout_BufferNew( p_dec->p_aout, p_dec->p_aout_input,
- A52_FRAME_NB );
- if ( p_buffer == NULL ) return -1;
- p_buffer->start_date = aout_DateGet( &p_dec->end_date );
- p_buffer->end_date = aout_DateIncrement( &p_dec->end_date,
- A52_FRAME_NB );
-
- /* FIXME */
- i_flags = A52_STEREO | A52_ADJUST_LEVEL;
- /* Do the actual decoding now */
- a52_frame( p_dec->p_a52_state, p_frame_buffer,
- &i_flags, &i_sample_level, 0 );
+ if (p_buf[5] >= 0x60) /* bsid >= 12 */
+ return 0;
+ half = halfrate[p_buf[5] >> 3];
- if( !p_dec->b_dynrng )
+ /* acmod, dsurmod and lfeon */
+ acmod = p_buf[6] >> 5;
+ if ( p_buf[6] & 0xf8 )
{
- a52_dynrng( p_dec->p_a52_state, NULL, NULL );
+ *pi_channels = AOUT_CHAN_DOLBY;
}
-
- for ( i = 0; i < 6; i++ )
+ else switch ( acmod )
{
- sample_t * p_samples;
-
- if( a52_block( p_dec->p_a52_state ) )
- {
- msg_Warn( p_dec->p_fifo, "a52_block failed for block %i", i );
- }
-
- p_samples = a52_samples( p_dec->p_a52_state );
-
- /* Interleave the *$£%ù samples */
- Interleave( (float *)(p_buffer->p_buffer + i * i_bytes_per_block),
- p_samples, p_dec->output_format.i_channels );
+ case 0x0: *pi_channels = AOUT_CHAN_CHANNEL; break;
+ case 0x1: *pi_channels = AOUT_CHAN_MONO; break;
+ case 0x2: *pi_channels = AOUT_CHAN_STEREO; break;
+ case 0x3: *pi_channels = AOUT_CHAN_3F; break;
+ case 0x4: *pi_channels = AOUT_CHAN_2F1R; break;
+ case 0x5: *pi_channels = AOUT_CHAN_3F1R; break;
+ case 0x6: *pi_channels = AOUT_CHAN_2F2R; break;
+ case 0x7: *pi_channels = AOUT_CHAN_3F2R; break;
+ case 0x8: *pi_channels = AOUT_CHAN_CHANNEL1; break;
+ case 0x9: *pi_channels = AOUT_CHAN_CHANNEL2; break;
}
+
+ if ( p_buf[6] & lfeon[acmod] ) *pi_channels |= AOUT_CHAN_LFE;
- aout_BufferPlay( p_dec->p_aout, p_dec->p_aout_input, p_buffer );
-
- return 0;
-}
-
-/*****************************************************************************
- * EndThread : liba52 decoder thread destruction
- *****************************************************************************/
-static void EndThread( a52_thread_t * p_dec )
-{
- if ( p_dec->p_aout_input != NULL )
- {
- aout_InputDelete( p_dec->p_aout, p_dec->p_aout_input );
+ frmsizecod = p_buf[4] & 63;
+ if (frmsizecod >= 38)
+ return 0;
+ bitrate = rate [frmsizecod >> 1];
+ *pi_bit_rate = (bitrate * 1000) >> half;
+
+ switch (p_buf[4] & 0xc0) {
+ case 0:
+ *pi_sample_rate = 48000 >> half;
+ return 4 * bitrate;
+ case 0x40:
+ *pi_sample_rate = 44100 >> half;
+ return 2 * (320 * bitrate / 147 + (frmsizecod & 1));
+ case 0x80:
+ *pi_sample_rate = 32000 >> half;
+ return 6 * bitrate;
+ default:
+ return 0;
}
-
- a52_free( p_dec->p_a52_state );
- free( p_dec );
}