* This plugin makes use of liba52 to decode A/52 audio
* (http://liba52.sf.net/).
*****************************************************************************
- * Copyright (C) 2001 VideoLAN
- * $Id: a52.c,v 1.1 2002/08/04 17:23:42 sam Exp $
+ * Copyright (C) 2001, 2002 VideoLAN
+ * $Id: a52.c,v 1.2 2002/08/07 21:36:56 massiot Exp $
*
* Authors: Gildas Bazin <gbazin@netcourrier.com>
+ * Christophe Massiot <massiot@via.ecp.fr>
*
* 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
#define A52DEC_FRAME_SIZE 1536
-/*
- * Global lock for accessing liba52 functions.
- * Currently, liba52 isn't thread-safe. So to prevent two threads from
- * using liba52 at the same time, we have to set up a global lock.
- * I know static variables aren't a good idea in multi-threaded programs,
- * but believe me, this is the way to go.
- * --Meuuh 2002-07-19
- */
-static vlc_mutex_t a52_lock;
-static vlc_bool_t b_liba52_initialized = 0;
-
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static int OpenDecoder ( vlc_object_t * );
static int RunDecoder ( decoder_fifo_t * );
-static int DecodeFrame ( a52_adec_thread_t * );
-static int InitThread ( a52_adec_thread_t * );
-static void EndThread ( a52_adec_thread_t * );
-
-static void BitstreamCallback ( bit_stream_t *, vlc_bool_t );
-static void float2s16_2 ( float *, int16_t * );
-static inline int16_t convert ( int32_t );
+static int DecodeFrame ( a52_thread_t *, u8 * );
+static int InitThread ( a52_thread_t *, decoder_fifo_t * );
+static void EndThread ( a52_thread_t * );
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int RunDecoder( decoder_fifo_t *p_fifo )
{
- a52_adec_thread_t *p_a52_adec;
+ a52_thread_t *p_a52;
/* Allocate the memory needed to store the thread's structure */
- p_a52_adec = (a52_adec_thread_t *)malloc( sizeof(a52_adec_thread_t) );
- if (p_a52_adec == NULL)
+ p_a52 = (a52_thread_t *)malloc( sizeof(a52_thread_t) );
+ if( p_a52 == NULL )
{
msg_Err( p_fifo, "out of memory" );
DecoderError( p_fifo );
- return( -1 );
+ return -1;
}
- /* FIXME */
- p_a52_adec->i_channels = 2;
-
- /*
- * Initialize the thread properties
- */
- p_a52_adec->p_aout_fifo = NULL;
- p_a52_adec->p_fifo = p_fifo;
-
- if( InitThread( p_a52_adec ) )
+ if( InitThread( p_a52, p_fifo ) )
{
- msg_Err( p_a52_adec->p_fifo, "could not initialize thread" );
+ msg_Err( p_a52->p_fifo, "could not initialize thread" );
DecoderError( p_fifo );
- free( p_a52_adec );
- return( -1 );
+ free( p_a52 );
+ return -1;
}
/* liba52 decoder thread's main loop */
- while( !p_a52_adec->p_fifo->b_die && !p_a52_adec->p_fifo->b_error )
+ while( !p_a52->p_fifo->b_die && !p_a52->p_fifo->b_error )
{
-
- /* look for sync word - should be 0x0b77 */
- RealignBits(&p_a52_adec->bit_stream);
- while( (ShowBits( &p_a52_adec->bit_stream, 16 ) ) != 0x0b77 &&
- (!p_a52_adec->p_fifo->b_die) && (!p_a52_adec->p_fifo->b_error))
+ int i_frame_size, i_flags, i_rate, i_bit_rate;
+ mtime_t pts;
+ /* Temporary buffer to store the raw frame to be decoded */
+ u8 p_frame_buffer[3840];
+
+ /* Look for sync word - should be 0x0b77 */
+ RealignBits(&p_a52->bit_stream);
+ while( (ShowBits( &p_a52->bit_stream, 16 ) ) != 0x0b77 &&
+ (!p_a52->p_fifo->b_die) && (!p_a52->p_fifo->b_error))
{
- RemoveBits( &p_a52_adec->bit_stream, 8 );
+ RemoveBits( &p_a52->bit_stream, 8 );
}
- /* get a52 frame header */
- GetChunk( &p_a52_adec->bit_stream, p_a52_adec->p_frame_buffer, 7 );
- if( p_a52_adec->p_fifo->b_die ) break;
+ /* Get A/52 frame header */
+ GetChunk( &p_a52->bit_stream, p_frame_buffer, 7 );
+ if( p_a52->p_fifo->b_die ) break;
- /* check if frame is valid and get frame info */
- vlc_mutex_lock( &a52_lock );
- p_a52_adec->frame_size = a52_syncinfo( p_a52_adec->p_frame_buffer,
- &p_a52_adec->flags,
- &p_a52_adec->sample_rate,
- &p_a52_adec->bit_rate );
- vlc_mutex_unlock( &a52_lock );
+ /* Check if frame is valid and get frame info */
+ i_frame_size = a52_syncinfo( p_frame_buffer, &i_flags, &i_rate,
+ &i_bit_rate );
- if( !p_a52_adec->frame_size )
+ if( !i_frame_size )
{
- msg_Warn( p_a52_adec->p_fifo, "a52_syncinfo failed" );
+ msg_Warn( p_a52->p_fifo, "a52_syncinfo failed" );
continue;
}
- if( DecodeFrame( p_a52_adec ) && !p_a52_adec->p_fifo->b_die )
+ if( (p_a52->p_aout_input != NULL) &&
+ ( (p_a52->output_format.i_rate != i_rate)
+ /* || (p_a52->output_format.i_channels != i_channels) */ ) )
{
- DecoderError( p_fifo );
- free( p_a52_adec );
- return( -1 );
+ /* Parameters changed - this should not happen. */
+ aout_InputDelete( p_a52->p_aout, p_a52->p_aout_input );
+ p_a52->p_aout_input = NULL;
}
+ /* Creating the audio input if not created yet. */
+ if( p_a52->p_aout_input == NULL )
+ {
+ p_a52->output_format.i_rate = i_rate;
+ /* p_a52->output_format.i_channels = i_channels; */
+ p_a52->p_aout_input = aout_InputNew( p_a52->p_fifo,
+ &p_a52->p_aout,
+ &p_a52->output_format );
+
+ if ( p_a52->p_aout_input == NULL )
+ {
+ p_a52->p_fifo->b_error = 1;
+ break;
+ }
+ }
+
+ /* Set the Presentation Time Stamp */
+ CurrentPTS( &p_a52->bit_stream, &pts, NULL );
+ if ( pts != 0 )
+ {
+ p_a52->last_date = pts;
+ }
+
+ /* Get the complete frame */
+ GetChunk( &p_a52->bit_stream, p_frame_buffer + 7,
+ i_frame_size - 7 );
+ if( p_a52->p_fifo->b_die ) break;
+
+ if( DecodeFrame( p_a52, p_frame_buffer ) )
+ {
+ p_a52->p_fifo->b_error = 1;
+ break;
+ }
}
/* If b_error is set, the decoder thread enters the error loop */
- if( p_a52_adec->p_fifo->b_error )
+ if( p_a52->p_fifo->b_error )
{
- DecoderError( p_a52_adec->p_fifo );
+ DecoderError( p_a52->p_fifo );
}
/* End of the liba52 decoder thread */
- EndThread( p_a52_adec );
+ EndThread( p_a52 );
- return( 0 );
+ return 0;
}
/*****************************************************************************
* InitThread: initialize data before entering main loop
*****************************************************************************/
-static int InitThread( a52_adec_thread_t * p_a52_adec )
+static int InitThread( a52_thread_t * p_a52, decoder_fifo_t * p_fifo )
{
- /* Initialize the global lock */
- vlc_mutex_lock( p_a52_adec->p_fifo->p_vlc->p_global_lock );
- if ( !b_liba52_initialized )
- {
- vlc_mutex_init( p_a52_adec->p_fifo, &a52_lock );
- b_liba52_initialized = 1;
- }
- vlc_mutex_unlock( p_a52_adec->p_fifo->p_vlc->p_global_lock );
+ /* Initialize the thread properties */
+ p_a52->p_aout = NULL;
+ p_a52->p_aout_input = NULL;
+ p_a52->p_fifo = p_fifo;
+ p_a52->output_format.i_format = AOUT_FMT_FLOAT32;
+ p_a52->output_format.i_channels = 2; /* FIXME ! */
+ p_a52->last_date = 0;
/* Initialize liba52 */
- vlc_mutex_lock( &a52_lock );
- p_a52_adec->p_a52_state = a52_init( 0 );
- vlc_mutex_unlock( &a52_lock );
- if( p_a52_adec->p_a52_state == NULL )
+ p_a52->p_a52_state = a52_init( 0 );
+ if( p_a52->p_a52_state == NULL )
{
- msg_Err( p_a52_adec->p_fifo, "unable to initialize liba52" );
+ msg_Err( p_a52->p_fifo, "unable to initialize liba52" );
return -1;
}
- p_a52_adec->b_dynrng = config_GetInt( p_a52_adec->p_fifo, "a52-dynrng" );
+ p_a52->b_dynrng = config_GetInt( p_a52->p_fifo, "a52-dynrng" );
/* Init the BitStream */
- InitBitstream( &p_a52_adec->bit_stream,
- p_a52_adec->p_fifo,
- BitstreamCallback, NULL );
+ InitBitstream( &p_a52->bit_stream, p_a52->p_fifo,
+ NULL, NULL );
- return( 0 );
+ return 0;
}
/*****************************************************************************
- * DecodeFrame: decodes an ATSC A/52 frame.
+ * Interleave: helper function to interleave channels
*****************************************************************************/
-static int DecodeFrame( a52_adec_thread_t * p_a52_adec )
+static void Interleave( float * p_out, float * p_in, int i_channels )
{
- sample_t sample_level = 1;
- byte_t *p_buffer;
- int i;
-
- if( ( p_a52_adec->p_aout_fifo != NULL ) &&
- ( p_a52_adec->p_aout_fifo->i_rate != p_a52_adec->sample_rate ) )
- {
- /* Make sure the output thread leaves the NextFrame() function */
- vlc_mutex_lock (&(p_a52_adec->p_aout_fifo->data_lock));
- aout_DestroyFifo (p_a52_adec->p_aout_fifo);
- vlc_cond_signal (&(p_a52_adec->p_aout_fifo->data_wait));
- vlc_mutex_unlock (&(p_a52_adec->p_aout_fifo->data_lock));
-
- p_a52_adec->p_aout_fifo = NULL;
- }
+ int i, j;
- /* Creating the audio output fifo if not created yet */
- if( p_a52_adec->p_aout_fifo == NULL )
+ for ( j = 0; j < i_channels; j++ )
{
- p_a52_adec->p_aout_fifo = aout_CreateFifo( p_a52_adec->p_fifo,
- AOUT_FIFO_PCM, p_a52_adec->i_channels,
- p_a52_adec->sample_rate,
- A52DEC_FRAME_SIZE * p_a52_adec->i_channels,
- NULL );
-
- if ( p_a52_adec->p_aout_fifo == NULL )
- {
- return( -1 );
+ for ( i = 0; i < 256; i++ )
+ {
+ p_out[i * i_channels + j] = p_in[j * 256 + i];
}
}
+}
- /* Set the Presentation Time Stamp */
- CurrentPTS( &p_a52_adec->bit_stream,
- &p_a52_adec->p_aout_fifo->date[
- p_a52_adec->p_aout_fifo->i_end_frame],
- NULL );
+/*****************************************************************************
+ * DecodeFrame: decode an ATSC A/52 frame.
+ *****************************************************************************/
+static int DecodeFrame( a52_thread_t * p_a52, u8 * p_frame_buffer )
+{
+ sample_t i_sample_level = 1;
+ aout_buffer_t * p_buffer;
+ int i, i_flags;
+ int i_bytes_per_block = 256 * p_a52->output_format.i_channels
+ * sizeof(float);
- if( !p_a52_adec->p_aout_fifo->date[
- p_a52_adec->p_aout_fifo->i_end_frame] )
+ if( !p_a52->last_date )
{
- p_a52_adec->p_aout_fifo->date[
- p_a52_adec->p_aout_fifo->i_end_frame] = LAST_MDATE;
+ /* We've just started the stream, wait for the first PTS. */
+ return 0;
}
-
-
- p_buffer = ((byte_t *)p_a52_adec->p_aout_fifo->buffer) +
- ( p_a52_adec->p_aout_fifo->i_end_frame * A52DEC_FRAME_SIZE *
- p_a52_adec->i_channels * sizeof(s16) );
+ p_buffer = aout_BufferNew( p_a52->p_aout, p_a52->p_aout_input,
+ A52DEC_FRAME_SIZE );
+ if ( p_buffer == NULL ) return -1;
+ p_buffer->start_date = p_a52->last_date;
+ p_a52->last_date += (mtime_t)(A52DEC_FRAME_SIZE * 1000000)
+ / p_a52->output_format.i_rate;
+ p_buffer->end_date = p_a52->last_date;
/* FIXME */
- p_a52_adec->flags = A52_STEREO | A52_ADJUST_LEVEL;
-
- /* Get the complete frame */
- GetChunk( &p_a52_adec->bit_stream, p_a52_adec->p_frame_buffer + 7,
- p_a52_adec->frame_size - 7 );
- if( p_a52_adec->p_fifo->b_die ) return( -1 );
+ i_flags = A52_STEREO | A52_ADJUST_LEVEL;
- /* do the actual decoding now */
- vlc_mutex_lock( &a52_lock );
- a52_frame( p_a52_adec->p_a52_state, p_a52_adec->p_frame_buffer,
- &p_a52_adec->flags, &sample_level, 384 );
+ /* Do the actual decoding now */
+ a52_frame( p_a52->p_a52_state, p_frame_buffer,
+ &i_flags, &i_sample_level, 0 );
- if( !p_a52_adec->b_dynrng )
- a52_dynrng( p_a52_adec->p_a52_state, NULL, NULL );
+ if( !p_a52->b_dynrng )
+ {
+ a52_dynrng( p_a52->p_a52_state, NULL, NULL );
+ }
- for( i = 0; i < 6; i++ )
+ for ( i = 0; i < 6; i++ )
{
- if( a52_block( p_a52_adec->p_a52_state ) )
+ sample_t * p_samples;
+
+ if( a52_block( p_a52->p_a52_state ) )
{
- msg_Warn( p_a52_adec->p_fifo, "a52_block failed for block %i", i );
+ msg_Warn( p_a52->p_fifo, "a52_block failed for block %i", i );
}
- float2s16_2( a52_samples( p_a52_adec->p_a52_state ),
- ((int16_t *)p_buffer) + i * 256 * p_a52_adec->i_channels );
- }
- vlc_mutex_unlock( &a52_lock );
+ p_samples = a52_samples( p_a52->p_a52_state );
+ /* Interleave the *$£%ù samples */
+ Interleave( (float *)(p_buffer->p_buffer + i * i_bytes_per_block),
+ p_samples, p_a52->output_format.i_channels );
+ }
- vlc_mutex_lock( &p_a52_adec->p_aout_fifo->data_lock );
- p_a52_adec->p_aout_fifo->i_end_frame =
- (p_a52_adec->p_aout_fifo->i_end_frame + 1) & AOUT_FIFO_SIZE;
- vlc_cond_signal (&p_a52_adec->p_aout_fifo->data_wait);
- vlc_mutex_unlock (&p_a52_adec->p_aout_fifo->data_lock);
+ aout_BufferPlay( p_a52->p_aout, p_a52->p_aout_input, p_buffer );
return 0;
}
/*****************************************************************************
* EndThread : liba52 decoder thread destruction
*****************************************************************************/
-static void EndThread (a52_adec_thread_t *p_a52_adec)
+static void EndThread (a52_thread_t *p_a52)
{
- /* If the audio output fifo was created, we destroy it */
- if (p_a52_adec->p_aout_fifo != NULL)
+ if ( p_a52->p_aout_input != NULL )
{
- aout_DestroyFifo (p_a52_adec->p_aout_fifo);
-
- /* Make sure the output thread leaves the NextFrame() function */
- vlc_mutex_lock (&(p_a52_adec->p_aout_fifo->data_lock));
- vlc_cond_signal (&(p_a52_adec->p_aout_fifo->data_wait));
- vlc_mutex_unlock (&(p_a52_adec->p_aout_fifo->data_lock));
+ aout_InputDelete( p_a52->p_aout, p_a52->p_aout_input );
}
- vlc_mutex_lock( &a52_lock );
- a52_free( p_a52_adec->p_a52_state );
- vlc_mutex_unlock( &a52_lock );
- free( p_a52_adec );
-
-}
-
-/*****************************************************************************
- * float2s16_2 : converts floats to ints using a trick based on the IEEE
- * floating-point format
- *****************************************************************************/
-static inline int16_t convert (int32_t i)
-{
- if (i > 0x43c07fff)
- return 32767;
- else if (i < 0x43bf8000)
- return -32768;
- else
- return i - 0x43c00000;
-}
-
-static void float2s16_2 (float * _f, int16_t * s16)
-{
- int i;
- int32_t * f = (int32_t *) _f;
-
- for (i = 0; i < 256; i++) {
- s16[2*i] = convert (f[i]);
- s16[2*i+1] = convert (f[i+256]);
- }
+ a52_free( p_a52->p_a52_state );
+ free( p_a52 );
}
-/*****************************************************************************
- * BitstreamCallback: Import parameters from the new data/PES packet
- *****************************************************************************
- * This function is called by input's NextDataPacket.
- *****************************************************************************/
-static void BitstreamCallback ( bit_stream_t * p_bit_stream,
- vlc_bool_t b_new_pes )
-{
- if( b_new_pes )
- {
- /* Drop special A52 header */
-/* p_bit_stream->p_byte += 3; */
- }
-}
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