-/*****************************************************************************
- * spdif.c: A/52 pass-through to external decoder with enabled soundcard
- *****************************************************************************
- * Copyright (C) 2001-2002 VideoLAN
- * $Id: spdif.c,v 1.8 2002/08/30 22:22:24 massiot Exp $
- *
- * Authors: Stéphane Borel <stef@via.ecp.fr>
- * Juha Yrjola <jyrjola@cc.hut.fi>
- * German Gomez Garcia <german@piraos.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
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
- *****************************************************************************/
-
-/*****************************************************************************
- * Preamble
- *****************************************************************************/
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h> /* memcpy() */
-#include <fcntl.h>
-
-#include <vlc/vlc.h>
-#include <vlc/decoder.h>
-#include <vlc/aout.h>
-
-#ifdef HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-#define A52_FRAME_NB 1536
-
-/*****************************************************************************
- * spdif_thread_t : A52 pass-through thread descriptor
- *****************************************************************************/
-typedef struct spdif_thread_s
-{
- /*
- * Thread properties
- */
- vlc_thread_t thread_id; /* id for thread functions */
-
- /*
- * Input properties
- */
- decoder_fifo_t * p_fifo; /* stores the PES stream 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;
-} spdif_thread_t;
-
-/****************************************************************************
- * Local prototypes
- ****************************************************************************/
-static int OpenDecoder ( vlc_object_t * );
-static int RunDecoder ( decoder_fifo_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
- *****************************************************************************/
-vlc_module_begin();
- set_description( _("SPDIF pass-through A52 decoder") );
- 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 chose.
- *****************************************************************************/
-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;
- }
-
- p_fifo->pf_run = RunDecoder;
- return VLC_SUCCESS;
-}
-
-/****************************************************************************
- * RunDecoder: the whole thing
- ****************************************************************************
- * This function is called just after the thread is launched.
- ****************************************************************************/
-static int RunDecoder( decoder_fifo_t *p_fifo )
-{
- spdif_thread_t * p_dec;
- audio_date_t end_date;
-
- /* Allocate the memory needed to store the thread's structure */
- 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 ) )
- {
-
- msg_Err( p_fifo, "could not initialize thread" );
- DecoderError( p_fifo );
- free( p_dec );
- return -1;
- }
-
- /* 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;
- mtime_t pts;
- /* Temporary buffer to store the raw frame to be decoded */
- 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))
- {
- RemoveBits( &p_dec->bit_stream, 8 );
- }
-
- /* Set the Presentation Time Stamp */
- NextPTS( &p_dec->bit_stream, &pts, NULL );
- if ( pts != 0 && pts != aout_DateGet( &end_date ) )
- {
- aout_DateSet( &end_date, pts );
- }
-
- /* Get A/52 frame header */
- 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 = SyncInfo( p_header, &i_flags, &i_rate,
- &i_bit_rate );
-
- if( !i_frame_size )
- {
- msg_Warn( p_dec->p_fifo, "a52_syncinfo failed" );
- continue;
- }
-
- if( (p_dec->p_aout_input != NULL) &&
- ( (p_dec->output_format.i_rate != i_rate)
- || (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 );
- p_dec->p_aout_input = NULL;
- }
-
- /* Creating the audio input if not created yet. */
- if( p_dec->p_aout_input == NULL )
- {
- p_dec->output_format.i_rate = i_rate;
- 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 );
-
- if ( p_dec->p_aout_input == NULL )
- {
- p_dec->p_fifo->b_error = 1;
- break;
- }
- }
-
- 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;
-
- /* 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 spdif thread enters the error loop */
- if( p_dec->p_fifo->b_error )
- {
- DecoderError( p_dec->p_fifo );
- }
-
- /* End of the spdif decoder thread */
- EndThread( p_dec );
-
- return 0;
-}
-
-/****************************************************************************
- * 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_A52;
- p_dec->output_format.i_channels = -1;
-
- /* Init the Bitstream */
- InitBitstream( &p_dec->bit_stream, p_dec->p_fifo,
- NULL, NULL );
-
- return 0;
-}
-
-/*****************************************************************************
- * EndThread : spdif thread destruction
- *****************************************************************************/
-static void EndThread( spdif_thread_t * p_dec )
-{
- if ( p_dec->p_aout_input != NULL )
- {
- aout_InputDelete( p_dec->p_aout, p_dec->p_aout_input );
- }
-
- free( p_dec );
-}
-
-/****************************************************************************
- * Local structures and tables
- ****************************************************************************/
-typedef struct sync_frame_s
-{
- struct syncinfo
- {
- u8 syncword[2];
- u8 crc1[2];
- u8 code;
- } syncinfo;
-
- struct bsi
- {
- u8 bsidmod;
- u8 acmod;
- } bsi;
-} sync_frame_t;
-
-typedef struct frame_size_s
-{
- u16 i_bit_rate;
- u16 i_frame_size[3];
-} frame_size_t;
-
-typedef struct info_s
-{
- int i_bit_rate;
- int i_frame_size;
- int i_sample_rate;
- int i_bs_mod;
-} info_t;
-
-static const frame_size_t p_frame_size_code[64] =
-{
- { 32 ,{64 ,69 ,96 } },
- { 32 ,{64 ,70 ,96 } },
- { 40 ,{80 ,87 ,120 } },
- { 40 ,{80 ,88 ,120 } },
- { 48 ,{96 ,104 ,144 } },
- { 48 ,{96 ,105 ,144 } },
- { 56 ,{112 ,121 ,168 } },
- { 56 ,{112 ,122 ,168 } },
- { 64 ,{128 ,139 ,192 } },
- { 64 ,{128 ,140 ,192 } },
- { 80 ,{160 ,174 ,240 } },
- { 80 ,{160 ,175 ,240 } },
- { 96 ,{192 ,208 ,288 } },
- { 96 ,{192 ,209 ,288 } },
- { 112 ,{224 ,243 ,336 } },
- { 112 ,{224 ,244 ,336 } },
- { 128 ,{256 ,278 ,384 } },
- { 128 ,{256 ,279 ,384 } },
- { 160 ,{320 ,348 ,480 } },
- { 160 ,{320 ,349 ,480 } },
- { 192 ,{384 ,417 ,576 } },
- { 192 ,{384 ,418 ,576 } },
- { 224 ,{448 ,487 ,672 } },
- { 224 ,{448 ,488 ,672 } },
- { 256 ,{512 ,557 ,768 } },
- { 256 ,{512 ,558 ,768 } },
- { 320 ,{640 ,696 ,960 } },
- { 320 ,{640 ,697 ,960 } },
- { 384 ,{768 ,835 ,1152 } },
- { 384 ,{768 ,836 ,1152 } },
- { 448 ,{896 ,975 ,1344 } },
- { 448 ,{896 ,976 ,1344 } },
- { 512 ,{1024 ,1114 ,1536 } },
- { 512 ,{1024 ,1115 ,1536 } },
- { 576 ,{1152 ,1253 ,1728 } },
- { 576 ,{1152 ,1254 ,1728 } },
- { 640 ,{1280 ,1393 ,1920 } },
- { 640 ,{1280 ,1394 ,1920 } }
-};
-
-/****************************************************************************
- * SyncInfo: parse A52 sync info
- ****************************************************************************
- * NB : i_flags is unused, this is just to mimick liba52's a52_syncinfo
- * Returns the frame size
- ****************************************************************************/
-static int SyncInfo( const byte_t * p_buffer, int * pi_flags, int * pi_rate,
- int * pi_bitrate )
-{
- static const int p_sample_rates[4] = { 48000, 44100, 32000, -1 };
- int i_frame_rate_code;
- int i_frame_size_code;
- const sync_frame_t * p_sync_frame;
-
- p_sync_frame = (const sync_frame_t *)p_buffer;
-
- /* Compute frame rate */
- i_frame_rate_code = (p_sync_frame->syncinfo.code >> 6) & 0x03;
- *pi_rate = p_sample_rates[i_frame_rate_code];
- if ( *pi_rate == -1 )
- {
- return 0;
- }
-
- if ( ( ( p_sync_frame->bsi.bsidmod >> 3 ) & 0x1f ) != 0x08 )
- {
- return 0;
- }
-
- /* Compute frame size */
- i_frame_size_code = p_sync_frame->syncinfo.code & 0x3f;
- *pi_bitrate = p_frame_size_code[i_frame_size_code].i_bit_rate;
-
- return ( 2 * p_frame_size_code[i_frame_size_code]
- .i_frame_size[i_frame_rate_code] );
-}