* a52.c: A/52 basic parser
*****************************************************************************
* Copyright (C) 2001-2002 VideoLAN
- * $Id: a52.c,v 1.23 2003/09/02 20:19:25 gbazin Exp $
+ * $Id: a52.c,v 1.24 2003/09/30 20:23:03 gbazin Exp $
*
* Authors: Stéphane Borel <stef@via.ecp.fr>
* Christophe Massiot <massiot@via.ecp.fr>
# include <unistd.h>
#endif
+#include "vlc_block_helper.h"
+
#define A52_HEADER_SIZE 7
/*****************************************************************************
/*
* Input properties
*/
- int i_state;
-
- uint8_t p_header[A52_HEADER_SIZE];
- int i_header;
-
- mtime_t pts;
+ int i_state;
+ vlc_bool_t b_synchro;
- int i_frame_size;
+ block_t *p_chain;
+ block_bytestream_t bytestream;
/*
* Decoder output properties
aout_instance_t * p_aout; /* opaque */
aout_input_t * p_aout_input; /* opaque */
audio_sample_format_t aout_format;
-
aout_buffer_t * p_aout_buffer; /* current aout buffer being filled */
/*
uint8_t *p_out_buffer; /* output buffer */
int i_out_buffer; /* position in output buffer */
audio_date_t end_date;
+
+ mtime_t pts;
+ int i_frame_size, i_bit_rate;
+ unsigned int i_rate, i_channels, i_channels_conf;
+
};
enum {
STATE_NOSYNC,
- STATE_PARTIAL_SYNC,
STATE_SYNC,
STATE_HEADER,
STATE_DATA
static int InitDecoder( decoder_t *p_dec )
{
p_dec->p_sys->i_state = STATE_NOSYNC;
+ p_dec->p_sys->b_synchro = VLC_FALSE;
p_dec->p_sys->p_out_buffer = NULL;
p_dec->p_sys->i_out_buffer = 0;
p_dec->p_sys->sout_format.i_cat = AUDIO_ES;
p_dec->p_sys->sout_format.i_fourcc = VLC_FOURCC( 'a', '5', '2', ' ' );
+ p_dec->p_sys->p_chain = NULL;
+
return VLC_SUCCESS;
}
static int RunDecoder( decoder_t *p_dec, block_t *p_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
- int i_block_pos = 0;
- mtime_t i_pts = p_block->i_pts;
+ uint8_t p_header[A52_HEADER_SIZE];
+
+ if( p_sys->p_chain )
+ {
+ block_ChainAppend( &p_sys->p_chain, p_block );
+ }
+ else
+ {
+ block_ChainAppend( &p_sys->p_chain, p_block );
+ p_sys->bytestream = block_BytestreamInit( p_dec, p_sys->p_chain, 0 );
+ }
- while( i_block_pos < p_block->i_buffer )
+ while( 1 )
{
switch( p_sys->i_state )
{
+
case STATE_NOSYNC:
- /* Look for sync word - should be 0x0b77 */
- while( i_block_pos < p_block->i_buffer &&
- p_block->p_buffer[i_block_pos] != 0x0b )
+ while( block_PeekBytes( &p_sys->bytestream, p_header, 2 )
+ == VLC_SUCCESS )
{
- i_block_pos++;
+ if( p_header[0] == 0x0b && p_header[1] == 0x77 )
+ {
+ p_sys->i_state = STATE_SYNC;
+ break;
+ }
+ block_SkipByte( &p_sys->bytestream );
+ p_dec->p_sys->b_synchro = VLC_FALSE;
}
-
- if( i_block_pos < p_block->i_buffer )
+ if( p_sys->i_state != STATE_SYNC )
{
- p_sys->i_state = STATE_PARTIAL_SYNC;
- i_block_pos++;
- p_sys->p_header[0] = 0x0b;
- break;
- }
- break;
+ block_ChainRelease( p_sys->p_chain );
+ p_sys->p_chain = NULL;
- case STATE_PARTIAL_SYNC:
- if( p_block->p_buffer[i_block_pos] == 0x77 )
- {
- p_sys->i_state = STATE_SYNC;
- i_block_pos++;
- p_sys->p_header[1] = 0x77;
- p_sys->i_header = 2;
+ /* Need more data */
+ return VLC_SUCCESS;
}
- else
- {
- p_sys->i_state = STATE_NOSYNC;
- }
- break;
case STATE_SYNC:
/* New frame, set the Presentation Time Stamp */
- p_sys->pts = i_pts; i_pts = 0;
+ p_sys->pts = p_sys->bytestream.p_block->i_pts;
if( p_sys->pts != 0 &&
p_sys->pts != aout_DateGet( &p_sys->end_date ) )
{
case STATE_HEADER:
/* Get A/52 frame header (A52_HEADER_SIZE bytes) */
- if( p_sys->i_header < A52_HEADER_SIZE )
+ if( block_PeekBytes( &p_sys->bytestream, p_header,
+ A52_HEADER_SIZE ) != VLC_SUCCESS )
{
- int i_size = __MIN( A52_HEADER_SIZE - p_sys->i_header,
- p_block->i_buffer - i_block_pos );
-
- memcpy( p_sys->p_header + p_sys->i_header,
- p_block->p_buffer + i_block_pos, i_size );
- i_block_pos += i_size;
- p_sys->i_header += i_size;
+ /* Need more data */
+ return VLC_SUCCESS;
}
- if( p_sys->i_header < A52_HEADER_SIZE )
- break;
-
- if( GetOutBuffer( p_dec, &p_sys->p_out_buffer )
- != VLC_SUCCESS )
- {
- block_Release( p_block );
- return VLC_EGENERIC;
- }
-
- if( !p_sys->p_out_buffer )
+ /* Check if frame is valid and get frame info */
+ p_sys->i_frame_size = SyncInfo( p_header,
+ &p_sys->i_channels,
+ &p_sys->i_channels_conf,
+ &p_sys->i_rate,
+ &p_sys->i_bit_rate );
+ if( !p_sys->i_frame_size )
{
+ msg_Dbg( p_dec, "emulated sync word" );
+ block_SkipByte( &p_sys->bytestream );
p_sys->i_state = STATE_NOSYNC;
+ p_dec->p_sys->b_synchro = VLC_FALSE;
break;
}
-
- memcpy( p_sys->p_out_buffer, p_sys->p_header, A52_HEADER_SIZE );
- p_sys->i_out_buffer = A52_HEADER_SIZE;
p_sys->i_state = STATE_DATA;
- break;
case STATE_DATA:
- /* Copy the whole A52 frame into the aout buffer */
- if( p_sys->i_out_buffer < p_sys->i_frame_size )
+ /* TODO: If p_block == NULL, flush the buffer without checking the
+ * next sync word */
+
+ if( !p_dec->p_sys->b_synchro )
{
- int i_size = __MIN( p_sys->i_frame_size - p_sys->i_out_buffer,
- p_block->i_buffer - i_block_pos );
+ /* Check if next expected frame contains the sync word */
+ if( block_PeekOffsetBytes( &p_sys->bytestream,
+ p_sys->i_frame_size, p_header, 2 )
+ != VLC_SUCCESS )
+ {
+ /* Need more data */
+ return VLC_SUCCESS;
+ }
+
+ if( p_header[0] != 0x0b || p_header[1] != 0x77 )
+ {
+ msg_Dbg( p_dec, "emulated sync word "
+ "(no sync on following frame)" );
+ p_sys->i_state = STATE_NOSYNC;
+ block_SkipByte( &p_sys->bytestream );
+ p_dec->p_sys->b_synchro = VLC_FALSE;
+ break;
+ }
+ }
- memcpy( p_sys->p_out_buffer + p_sys->i_out_buffer,
- p_block->p_buffer + i_block_pos, i_size );
- i_block_pos += i_size;
- p_sys->i_out_buffer += i_size;
+ if( !p_dec->p_sys->p_out_buffer )
+ if( GetOutBuffer( p_dec, &p_sys->p_out_buffer ) != VLC_SUCCESS )
+ {
+ return VLC_EGENERIC;
}
- if( p_sys->i_out_buffer < p_sys->i_frame_size )
- break; /* Need more data */
+ /* Copy the whole frame into the buffer */
+ if( block_GetBytes( &p_sys->bytestream, p_sys->p_out_buffer,
+ p_sys->i_frame_size ) != VLC_SUCCESS )
+ {
+ /* Need more data */
+ return VLC_SUCCESS;
+ }
- SendOutBuffer( p_dec );
+ p_sys->p_chain = block_BytestreamFlush( &p_sys->bytestream );
+ SendOutBuffer( p_dec );
p_sys->i_state = STATE_NOSYNC;
- break;
+ p_dec->p_sys->b_synchro = VLC_TRUE;
+
+ /* Make sure we don't reuse the same pts twice */
+ if( p_sys->pts == p_sys->bytestream.p_block->i_pts )
+ p_sys->pts = p_sys->bytestream.p_block->i_pts = 0;
}
}
- block_Release( p_block );
return VLC_SUCCESS;
}
sout_InputDelete( p_dec->p_sys->p_sout_input );
}
+ if( p_dec->p_sys->p_chain ) block_ChainRelease( p_sys->p_chain );
+
free( p_dec->p_sys );
return VLC_SUCCESS;
/*****************************************************************************
* GetOutBuffer:
*****************************************************************************/
-static int GetOutBuffer ( decoder_t *p_dec, uint8_t **pp_out_buffer )
+static int GetOutBuffer( decoder_t *p_dec, uint8_t **pp_out_buffer )
{
decoder_sys_t *p_sys = p_dec->p_sys;
int i_ret;
*****************************************************************************/
static int GetAoutBuffer( decoder_t *p_dec, aout_buffer_t **pp_buffer )
{
- int i_bit_rate;
- unsigned int i_rate, i_channels, i_channels_conf;
-
decoder_sys_t *p_sys = p_dec->p_sys;
- /* Check if frame is valid and get frame info */
- p_sys->i_frame_size = SyncInfo( p_sys->p_header,
- &i_channels, &i_channels_conf,
- &i_rate, &i_bit_rate );
-
- if( !p_sys->i_frame_size )
- {
- msg_Warn( p_dec, "a52 syncinfo failed" );
- *pp_buffer = NULL;
- return VLC_SUCCESS;
- }
-
- if( p_sys->p_aout_input != NULL && ( p_sys->aout_format.i_rate != i_rate
- || p_sys->aout_format.i_original_channels != i_channels_conf
+ if( p_sys->p_aout_input != NULL &&
+ ( p_sys->aout_format.i_rate != p_sys->i_rate
+ || p_sys->aout_format.i_original_channels != p_sys->i_channels_conf
|| (int)p_sys->aout_format.i_bytes_per_frame != p_sys->i_frame_size ) )
{
/* Parameters changed - this should not happen. */
/* Creating the audio input if not created yet. */
if( p_sys->p_aout_input == NULL )
{
- p_sys->aout_format.i_rate = i_rate;
- p_sys->aout_format.i_original_channels = i_channels_conf;
+ p_sys->aout_format.i_rate = p_sys->i_rate;
+ p_sys->aout_format.i_original_channels = p_sys->i_channels_conf;
p_sys->aout_format.i_physical_channels
- = i_channels_conf & AOUT_CHAN_PHYSMASK;
+ = p_sys->i_channels_conf & AOUT_CHAN_PHYSMASK;
p_sys->aout_format.i_bytes_per_frame = p_sys->i_frame_size;
p_sys->aout_format.i_frame_length = A52_FRAME_NB;
- aout_DateInit( &p_sys->end_date, i_rate );
+ aout_DateInit( &p_sys->end_date, p_sys->i_rate );
aout_DateSet( &p_sys->end_date, p_sys->pts );
p_sys->p_aout_input = aout_DecNew( p_dec,
&p_sys->p_aout,
*****************************************************************************/
static int GetSoutBuffer( decoder_t *p_dec, sout_buffer_t **pp_buffer )
{
- int i_bit_rate;
- unsigned int i_rate, i_channels, i_channels_conf;
-
decoder_sys_t *p_sys = p_dec->p_sys;
- /* Check if frame is valid and get frame info */
- p_sys->i_frame_size = SyncInfo( p_sys->p_header,
- &i_channels, &i_channels_conf,
- &i_rate, &i_bit_rate );
-
- if( !p_sys->i_frame_size )
- {
- msg_Warn( p_dec, "a52 syncinfo failed" );
- *pp_buffer = NULL;
- return VLC_SUCCESS;
- }
-
if( p_sys->p_sout_input != NULL &&
- ( p_sys->sout_format.i_sample_rate != (int)i_rate
- || p_sys->sout_format.i_channels != (int)i_channels ) )
+ ( p_sys->sout_format.i_sample_rate != (int)p_sys->i_rate
+ || p_sys->sout_format.i_channels != (int)p_sys->i_channels ) )
{
/* Parameters changed - this should not happen. */
}
/* Creating the sout input if not created yet. */
if( p_sys->p_sout_input == NULL )
{
- p_sys->sout_format.i_sample_rate = i_rate;
- p_sys->sout_format.i_channels = i_channels;
+ p_sys->sout_format.i_sample_rate = p_sys->i_rate;
+ p_sys->sout_format.i_channels = p_sys->i_channels;
p_sys->sout_format.i_block_align = 0;
- p_sys->sout_format.i_bitrate = i_bit_rate;
+ p_sys->sout_format.i_bitrate = p_sys->i_bit_rate;
p_sys->sout_format.i_extra_data = 0;
p_sys->sout_format.p_extra_data = NULL;
- aout_DateInit( &p_sys->end_date, i_rate );
+ aout_DateInit( &p_sys->end_date, p_sys->i_rate );
aout_DateSet( &p_sys->end_date, p_sys->pts );
- p_sys->p_sout_input = sout_InputNew( p_dec,
- &p_sys->sout_format );
-
+ p_sys->p_sout_input = sout_InputNew( p_dec, &p_sys->sout_format );
if( p_sys->p_sout_input == NULL )
{
msg_Err( p_dec, "cannot add a new stream" );
return VLC_EGENERIC;
}
msg_Info( p_dec, "A/52 channels:%d samplerate:%d bitrate:%d",
- i_channels, i_rate, i_bit_rate );
+ p_sys->i_channels, p_sys->i_rate, p_sys->i_bit_rate );
}
if( !aout_DateGet( &p_sys->end_date ) )
p_sys->p_aout_buffer = NULL;
}
+ p_dec->p_sys->p_out_buffer = NULL;
+
return VLC_SUCCESS;
}
projects / vlc / blobdiff