--- /dev/null
+/*****************************************************************************
+ * a52.c : raw A/52 stream input module for vlc
+ *****************************************************************************
+ * Copyright (C) 2001 VideoLAN
+ * $Id: a52.c,v 1.1 2004/02/13 21:48:32 gbazin Exp $
+ *
+ * Authors: Gildas Bazin <gbazin@netcourrier.com>
+ *
+ * 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 <vlc/vlc.h>
+#include <vlc/input.h>
+#include <vlc_codec.h>
+
+#define A52_PACKET_SIZE 16384
+#define A52_MAX_HEADER_SIZE 11
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int Open ( vlc_object_t * );
+static void Close ( vlc_object_t * );
+static int Demux ( input_thread_t * );
+
+static int Control( input_thread_t *, int, va_list );
+
+struct demux_sys_t
+{
+ vlc_bool_t b_start;
+ es_out_id_t *p_es;
+
+ /* Packetizer */
+ decoder_t *p_packetizer;
+
+ int i_mux_rate;
+ vlc_bool_t b_big_endian;
+};
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+vlc_module_begin();
+ set_description( _("Raw A/52 demuxer") );
+ set_capability( "demux", 155 );
+ set_callbacks( Open, Close );
+ add_shortcut( "a52" );
+vlc_module_end();
+
+/*****************************************************************************
+ * CheckSync: Check if buffer starts with an A52 sync code
+ *****************************************************************************/
+int CheckSync( uint8_t *p_peek, vlc_bool_t *p_big_endian )
+{
+ /* Little endian version of the bitstream */
+ if( p_peek[0] == 0x77 && p_peek[1] == 0x0b &&
+ p_peek[4] < 0x60 /* bsid < 12 */ )
+ {
+ return VLC_SUCCESS;
+ }
+ /* Big endian version of the bitstream */
+ else if( p_peek[0] == 0x0b && p_peek[1] == 0x77 &&
+ p_peek[5] < 0x60 /* bsid < 12 */ )
+ {
+ return VLC_SUCCESS;
+ }
+
+ return VLC_EGENERIC;
+}
+
+/*****************************************************************************
+ * Open: initializes ES structures
+ *****************************************************************************/
+static int Open( vlc_object_t * p_this )
+{
+ input_thread_t *p_input = (input_thread_t *)p_this;
+ demux_sys_t *p_sys;
+ byte_t * p_peek;
+ int i_peek = 0;
+ vlc_bool_t b_big_endian;
+
+ p_input->pf_demux = Demux;
+ p_input->pf_demux_control = Control;
+ p_input->pf_rewind = NULL;
+
+ /* Check if we are dealing with a WAV file */
+ if( input_Peek( p_input, &p_peek, 12 ) == 12 &&
+ !strncmp( p_peek, "RIFF", 4 ) && !strncmp( &p_peek[8], "WAVE", 4 ) )
+ {
+ int i_size;
+
+ /* Skip the wave header */
+ i_peek = 12 + 8;
+ while( input_Peek( p_input, &p_peek, i_peek ) == i_peek &&
+ strncmp( p_peek + i_peek - 8, "data", 4 ) )
+ {
+ i_peek += GetDWLE( p_peek + i_peek - 4 ) + 8;
+ }
+
+ /* TODO: should check wave format and sample_rate */
+
+ /* Some A52 wav files don't begin with a sync code so we do a more
+ * extensive search */
+ i_size = input_Peek( p_input, &p_peek, i_peek + A52_PACKET_SIZE * 2);
+ i_size -= A52_MAX_HEADER_SIZE;
+
+ while( i_peek < i_size )
+ {
+ if( CheckSync( p_peek + i_peek, &b_big_endian ) != VLC_SUCCESS )
+ /* The data is stored in 16 bits words */
+ i_peek += 2;
+ else
+ break;
+ }
+ }
+
+ /* Have a peep at the show. */
+ if( input_Peek( p_input, &p_peek, i_peek + A52_MAX_HEADER_SIZE * 2 ) <
+ i_peek + A52_MAX_HEADER_SIZE * 2 )
+ {
+ /* Stream too short */
+ msg_Warn( p_input, "cannot peek()" );
+ return VLC_EGENERIC;
+ }
+
+ if( CheckSync( p_peek + i_peek, &b_big_endian ) != VLC_SUCCESS )
+ {
+ if( p_input->psz_demux && !strncmp( p_input->psz_demux, "a52", 3 ) )
+ {
+ /* User forced */
+ msg_Err( p_input, "this doesn't look like a A52 audio stream, "
+ "continuing anyway" );
+ }
+ else
+ {
+ return VLC_EGENERIC;
+ }
+ }
+
+ p_input->p_demux_data = p_sys = malloc( sizeof( demux_sys_t ) );
+ p_sys->b_start = VLC_TRUE;
+ p_sys->i_mux_rate = 0;
+ p_sys->b_big_endian = b_big_endian;
+
+ /*
+ * Load the A52 packetizer
+ */
+ p_sys->p_packetizer = vlc_object_create( p_input, VLC_OBJECT_DECODER );
+ p_sys->p_packetizer->pf_decode_audio = 0;
+ p_sys->p_packetizer->pf_decode_video = 0;
+ p_sys->p_packetizer->pf_decode_sub = 0;
+ p_sys->p_packetizer->pf_packetize = 0;
+
+ /* Initialization of decoder structure */
+ es_format_Init( &p_sys->p_packetizer->fmt_in, AUDIO_ES,
+ VLC_FOURCC( 'a', '5', '2', ' ' ) );
+
+ p_sys->p_packetizer->p_module =
+ module_Need( p_sys->p_packetizer, "packetizer", NULL );
+ if( !p_sys->p_packetizer->p_module )
+ {
+ msg_Err( p_input, "cannot find A52 packetizer" );
+ return VLC_EGENERIC;
+ }
+
+ /* Create one program */
+ vlc_mutex_lock( &p_input->stream.stream_lock );
+ if( input_InitStream( p_input, 0 ) == -1 )
+ {
+ vlc_mutex_unlock( &p_input->stream.stream_lock );
+ msg_Err( p_input, "cannot init stream" );
+ return VLC_EGENERIC;
+ }
+ p_input->stream.i_mux_rate = 0;
+ vlc_mutex_unlock( &p_input->stream.stream_lock );
+
+ p_sys->p_es =
+ es_out_Add( p_input->p_es_out, &p_sys->p_packetizer->fmt_in );
+
+ return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * Close: frees unused data
+ *****************************************************************************/
+static void Close( vlc_object_t * p_this )
+{
+ input_thread_t *p_input = (input_thread_t*)p_this;
+ demux_sys_t *p_sys = p_input->p_demux_data;
+
+ /* Unneed module */
+ module_Unneed( p_sys->p_packetizer, p_sys->p_packetizer->p_module );
+
+ /* Delete the decoder */
+ vlc_object_destroy( p_sys->p_packetizer );
+
+ free( p_sys );
+}
+
+/*****************************************************************************
+ * Demux: reads and demuxes data packets
+ *****************************************************************************
+ * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
+ *****************************************************************************/
+static int Demux( input_thread_t * p_input )
+{
+ demux_sys_t *p_sys = p_input->p_demux_data;
+ block_t *p_block_in, *p_block_out;
+
+ if( !( p_block_in = stream_Block( p_input->s, A52_PACKET_SIZE ) ) )
+ {
+ return 0;
+ }
+
+ if( !p_sys->b_big_endian && p_block_in->i_buffer )
+ {
+ /* Convert to big endian */
+ int64_t i_pos = stream_Tell( p_input->s );
+ if( i_pos % 2 ) p_block_in->p_buffer++; /* Align stream */
+
+#ifdef HAVE_SWAB
+ swab(p_block_in->p_buffer, p_block_in->p_buffer, p_block_in->i_buffer);
+
+#else
+ int i;
+ byte_t *p_tmp, tmp;
+ p_tmp = p_block_in->p_buffer;
+ for( i = p_block_in->i_buffer / 2 ; i-- ; )
+ {
+ tmp = p_tmp[0];
+ p_tmp[0] = p_tmp[1];
+ p_tmp[1] = tmp;
+ p_tmp += 2;
+ }
+#endif
+ }
+
+ if( p_sys->b_start )
+ p_block_in->i_pts = p_block_in->i_dts = 1;
+ else
+ p_block_in->i_pts = p_block_in->i_dts = 0;
+
+ while( (p_block_out = p_sys->p_packetizer->pf_packetize(
+ p_sys->p_packetizer, &p_block_in )) )
+ {
+ p_sys->b_start = VLC_FALSE;
+
+ while( p_block_out )
+ {
+ block_t *p_next = p_block_out->p_next;
+
+ /* We assume a constant bitrate */
+ if( p_block_out->i_length )
+ p_sys->i_mux_rate =
+ p_block_out->i_buffer * I64C(1000000) / p_block_out->i_length;
+ p_input->stream.i_mux_rate = p_sys->i_mux_rate / 50;
+
+ input_ClockManageRef( p_input,
+ p_input->stream.p_selected_program,
+ p_block_out->i_pts * 9 / 100 );
+
+ p_block_in->b_discontinuity = 0;
+ p_block_out->i_dts = p_block_out->i_pts =
+ input_ClockGetTS( p_input, p_input->stream.p_selected_program,
+ p_block_out->i_pts * 9 / 100 );
+
+ es_out_Send( p_input->p_es_out, p_sys->p_es, p_block_out );
+
+ p_block_out = p_next;
+ }
+ }
+
+ return 1;
+}
+
+/*****************************************************************************
+ * Control:
+ *****************************************************************************/
+static int Control( input_thread_t *p_input, int i_query, va_list args )
+{
+ demux_sys_t *p_sys = (demux_sys_t *)p_input->p_demux_data;
+ int64_t *pi64;
+
+ switch( i_query )
+ {
+ case DEMUX_GET_TIME:
+ pi64 = (int64_t*)va_arg( args, int64_t * );
+ if( p_sys->i_mux_rate > 0 )
+ {
+ *pi64 = I64C(1000000) * stream_Tell( p_input->s ) /
+ p_sys->i_mux_rate;
+ return VLC_SUCCESS;
+ }
+ *pi64 = 0;
+ return VLC_EGENERIC;
+
+ case DEMUX_GET_LENGTH:
+ pi64 = (int64_t*)va_arg( args, int64_t * );
+ if( p_sys->i_mux_rate > 0 )
+ {
+ *pi64 = I64C(1000000) * stream_Size( p_input->s ) /
+ p_sys->i_mux_rate;
+ return VLC_SUCCESS;
+ }
+ *pi64 = 0;
+ return VLC_EGENERIC;
+
+ default:
+ return demux_vaControlDefault( p_input, i_query, args );
+ }
+}
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