/***************************************************************************** * ps.c: MPEG PS (ISO/IEC 13818-1) / MPEG SYSTEM (ISO/IEC 1172-1) * multiplexer module for vlc ***************************************************************************** * Copyright (C) 2001, 2002 VLC authors and VideoLAN * $Id$ * * Authors: Laurent Aimar * Eric Petit * Gildas Bazin * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ /***************************************************************************** * Preamble *****************************************************************************/ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include "bits.h" #include "pes.h" #include /***************************************************************************** * Module descriptor *****************************************************************************/ #define DTS_TEXT N_("DTS delay (ms)") #define DTS_LONGTEXT N_("Delay the DTS (decoding time " \ "stamps) and PTS (presentation timestamps) of the data in the " \ "stream, compared to the SCRs. This allows for some buffering inside " \ "the client decoder.") #define PES_SIZE_TEXT N_("PES maximum size") #define PES_SIZE_LONGTEXT N_("Set the maximum allowed PES "\ "size when producing the MPEG PS streams.") static int Open ( vlc_object_t * ); static void Close ( vlc_object_t * ); #define SOUT_CFG_PREFIX "sout-ps-" vlc_module_begin () set_description( N_("PS muxer") ) set_shortname( "MPEG-PS" ) set_category( CAT_SOUT ) set_subcategory( SUBCAT_SOUT_MUX ) set_capability( "sout mux", 50 ) add_shortcut( "ps", "mpeg1", "dvd" ) set_callbacks( Open, Close ) add_integer( SOUT_CFG_PREFIX "dts-delay", 200, DTS_TEXT, DTS_LONGTEXT, true ) add_integer( SOUT_CFG_PREFIX "pes-max-size", PES_PAYLOAD_SIZE_MAX, PES_SIZE_TEXT, PES_SIZE_LONGTEXT, true ) vlc_module_end () /***************************************************************************** * Exported prototypes *****************************************************************************/ static int Control ( sout_mux_t *, int, va_list ); static int AddStream( sout_mux_t *, sout_input_t * ); static void DelStream( sout_mux_t *, sout_input_t * ); static int Mux ( sout_mux_t * ); /***************************************************************************** * Local prototypes *****************************************************************************/ static void MuxWritePackHeader ( sout_mux_t *, block_t **, vlc_tick_t ); static void MuxWriteSystemHeader( sout_mux_t *, block_t **, vlc_tick_t ); static void MuxWritePSM ( sout_mux_t *, block_t **, vlc_tick_t ); static void StreamIdInit ( bool *id, int i_range ); static int StreamIdGet ( bool *id, int i_id_min, int i_id_max ); static void StreamIdRelease ( bool *id, int i_id_min, int i_id ); typedef struct ps_stream_s { int i_stream_id; int i_stream_type; int i_max_buff_size; /* used in system header */ /* Language is iso639-2T */ uint8_t lang[3]; } ps_stream_t; struct sout_mux_sys_t { /* Which id are unused */ bool stream_id_mpga[16]; /* 0xc0 -> 0xcf */ bool stream_id_mpgv[16]; /* 0xe0 -> 0xef */ bool stream_id_a52[8]; /* 0x80 -> 0x87 <- FIXME I'm not sure */ bool stream_id_spu[32]; /* 0x20 -> 0x3f */ bool stream_id_dts[8]; /* 0x88 -> 0x8f */ bool stream_id_lpcm[16]; /* 0xa0 -> 0xaf */ int i_audio_bound; int i_video_bound; int i_pes_count; int i_system_header; int i_dts_delay; int i_rate_bound; /* units of 50 bytes/second */ int64_t i_instant_bitrate; int64_t i_instant_size; int64_t i_instant_dts; bool b_mpeg2; int i_pes_max_size; int i_psm_version; uint32_t crc32_table[256]; }; static const char *const ppsz_sout_options[] = { "dts-delay", "pes-max-size", NULL }; /***************************************************************************** * Open: *****************************************************************************/ static int Open( vlc_object_t *p_this ) { sout_mux_t *p_mux = (sout_mux_t*)p_this; sout_mux_sys_t *p_sys; vlc_value_t val; msg_Info( p_mux, "Open" ); config_ChainParse( p_mux, SOUT_CFG_PREFIX, ppsz_sout_options, p_mux->p_cfg ); p_mux->pf_control = Control; p_mux->pf_addstream = AddStream; p_mux->pf_delstream = DelStream; p_mux->pf_mux = Mux; p_mux->p_sys = p_sys = malloc( sizeof( sout_mux_sys_t ) ); /* Init free stream id */ StreamIdInit( p_sys->stream_id_a52, 8 ); StreamIdInit( p_sys->stream_id_dts, 8 ); StreamIdInit( p_sys->stream_id_mpga, 16 ); StreamIdInit( p_sys->stream_id_mpgv, 16 ); StreamIdInit( p_sys->stream_id_lpcm, 16 ); StreamIdInit( p_sys->stream_id_spu, 32 ); p_sys->i_audio_bound = 0; p_sys->i_video_bound = 0; p_sys->i_system_header = 0; p_sys->i_pes_count = 0; p_sys->i_psm_version = 0; p_sys->i_instant_bitrate = 0; p_sys->i_instant_size = 0; p_sys->i_instant_dts = 0; p_sys->i_rate_bound = 0; p_sys->b_mpeg2 = !(p_mux->psz_mux && !strcmp( p_mux->psz_mux, "mpeg1" )); var_Get( p_mux, SOUT_CFG_PREFIX "dts-delay", &val ); p_sys->i_dts_delay = (int64_t)val.i_int * 1000; var_Get( p_mux, SOUT_CFG_PREFIX "pes-max-size", &val ); p_sys->i_pes_max_size = (int64_t)val.i_int; /* Initialise CRC32 table */ if( p_sys->b_mpeg2 ) { uint32_t i, j, k; for( i = 0; i < 256; i++ ) { k = 0; for( j = (i << 24) | 0x800000; j != 0x80000000; j <<= 1 ) k = (k << 1) ^ (((k ^ j) & 0x80000000) ? 0x04c11db7 : 0); p_sys->crc32_table[i] = k; } } return VLC_SUCCESS; } /***************************************************************************** * Close: *****************************************************************************/ static void Close( vlc_object_t * p_this ) { sout_mux_t *p_mux = (sout_mux_t*)p_this; sout_mux_sys_t *p_sys = p_mux->p_sys; block_t *p_end; msg_Info( p_mux, "Close" ); p_end = block_Alloc( 4 ); if( p_end ) { p_end->p_buffer[0] = 0x00; p_end->p_buffer[1] = 0x00; p_end->p_buffer[2] = 0x01; p_end->p_buffer[3] = 0xb9; sout_AccessOutWrite( p_mux->p_access, p_end ); } free( p_sys ); } /***************************************************************************** * Control: *****************************************************************************/ static int Control( sout_mux_t *p_mux, int i_query, va_list args ) { VLC_UNUSED(p_mux); bool *pb_bool; char **ppsz; switch( i_query ) { case MUX_CAN_ADD_STREAM_WHILE_MUXING: pb_bool = va_arg( args, bool * ); *pb_bool = true; return VLC_SUCCESS; case MUX_GET_ADD_STREAM_WAIT: pb_bool = va_arg( args, bool * ); *pb_bool = false; return VLC_SUCCESS; case MUX_GET_MIME: ppsz = va_arg( args, char ** ); *ppsz = strdup( "video/mpeg" ); return VLC_SUCCESS; default: return VLC_EGENERIC; } } /***************************************************************************** * AddStream: *****************************************************************************/ static int AddStream( sout_mux_t *p_mux, sout_input_t *p_input ) { sout_mux_sys_t *p_sys = p_mux->p_sys; ps_stream_t *p_stream; msg_Dbg( p_mux, "adding input codec=%4.4s", (char*)&p_input->p_fmt->i_codec ); p_input->p_sys = p_stream = malloc( sizeof( ps_stream_t ) ); if( unlikely(p_input->p_sys == NULL) ) return VLC_ENOMEM; p_stream->i_stream_type = 0x81; /* Init this new stream */ switch( p_input->p_fmt->i_codec ) { case VLC_CODEC_MPGV: case VLC_CODEC_MP2V: case VLC_CODEC_MP1V: p_stream->i_stream_id = StreamIdGet( p_sys->stream_id_mpgv, 0xe0, 0xef ); p_stream->i_stream_type = 0x02; /* ISO/IEC 13818 Video */ break; case VLC_CODEC_MP4V: p_stream->i_stream_id = StreamIdGet( p_sys->stream_id_mpgv, 0xe0, 0xef ); p_stream->i_stream_type = 0x10; break; case VLC_CODEC_H264: p_stream->i_stream_id = StreamIdGet( p_sys->stream_id_mpgv, 0xe0, 0xef ); p_stream->i_stream_type = 0x1b; break; case VLC_CODEC_DVD_LPCM: p_stream->i_stream_id = 0xbd00 | StreamIdGet( p_sys->stream_id_lpcm, 0xa0, 0xaf ); break; case VLC_CODEC_DTS: p_stream->i_stream_id = 0xbd00 | StreamIdGet( p_sys->stream_id_dts, 0x88, 0x8f ); break; case VLC_CODEC_A52: p_stream->i_stream_id = 0xbd00 | StreamIdGet( p_sys->stream_id_a52, 0x80, 0x87 ); break; case VLC_CODEC_MPGA: p_stream->i_stream_id = StreamIdGet( p_sys->stream_id_mpga, 0xc0, 0xcf ); p_stream->i_stream_type = 0x03; /* ISO/IEC 11172 Audio */ break; case VLC_CODEC_MP4A: p_stream->i_stream_id = StreamIdGet( p_sys->stream_id_mpga, 0xc0, 0xcf ); p_stream->i_stream_type = 0x0f; break; case VLC_CODEC_SPU: p_stream->i_stream_id = 0xbd00 | StreamIdGet( p_sys->stream_id_spu, 0x20, 0x3f ); break; default: goto error; } if( p_stream->i_stream_id < 0 ) goto error; if( p_input->p_fmt->i_cat == AUDIO_ES ) { p_sys->i_audio_bound++; p_stream->i_max_buff_size = 4 * 1024; } else if( p_input->p_fmt->i_cat == VIDEO_ES ) { p_sys->i_video_bound++; p_stream->i_max_buff_size = 400 * 1024; /* FIXME -- VCD uses 46, SVCD uses 230, ffmpeg has 230 with a note that it is small */ } else { /* FIXME -- what's valid for not audio or video? */ p_stream->i_max_buff_size = 4 * 1024; } /* Try to set a sensible default value for the instant bitrate */ p_sys->i_instant_bitrate += p_input->p_fmt->i_bitrate + 1000/* overhead */; /* FIXME -- spec requires an upper limit rate boundary in the system header; our codecs are VBR; using 2x nominal rate, convert to 50 bytes/sec */ p_sys->i_rate_bound += p_input->p_fmt->i_bitrate * 2 / (8 * 50); p_sys->i_psm_version++; p_stream->lang[0] = p_stream->lang[1] = p_stream->lang[2] = 0; if( p_input->p_fmt->psz_language ) { char *psz = p_input->p_fmt->psz_language; const iso639_lang_t *pl = NULL; if( strlen( psz ) == 2 ) { pl = GetLang_1( psz ); } else if( strlen( psz ) == 3 ) { pl = GetLang_2B( psz ); if( !strcmp( pl->psz_iso639_1, "??" ) ) { pl = GetLang_2T( psz ); } } if( pl && strcmp( pl->psz_iso639_1, "??" ) ) { p_stream->lang[0] = pl->psz_iso639_2T[0]; p_stream->lang[1] = pl->psz_iso639_2T[1]; p_stream->lang[2] = pl->psz_iso639_2T[2]; msg_Dbg( p_mux, " - lang=%c%c%c", p_stream->lang[0], p_stream->lang[1], p_stream->lang[2] ); } } return VLC_SUCCESS; error: free( p_stream ); return VLC_EGENERIC; } /***************************************************************************** * DelStream: *****************************************************************************/ static void DelStream( sout_mux_t *p_mux, sout_input_t *p_input ) { sout_mux_sys_t *p_sys = p_mux->p_sys; ps_stream_t *p_stream =(ps_stream_t*)p_input->p_sys; msg_Dbg( p_mux, "removing input" ); switch( p_input->p_fmt->i_codec ) { case VLC_CODEC_MPGV: StreamIdRelease( p_sys->stream_id_mpgv, 0xe0, p_stream->i_stream_id ); break; case VLC_CODEC_DVD_LPCM: StreamIdRelease( p_sys->stream_id_lpcm, 0xa0, p_stream->i_stream_id&0xff ); break; case VLC_CODEC_DTS: StreamIdRelease( p_sys->stream_id_dts, 0x88, p_stream->i_stream_id&0xff ); break; case VLC_CODEC_A52: StreamIdRelease( p_sys->stream_id_a52, 0x80, p_stream->i_stream_id&0xff ); break; case VLC_CODEC_MPGA: StreamIdRelease( p_sys->stream_id_mpga, 0xc0, p_stream->i_stream_id ); break; case VLC_CODEC_SPU: StreamIdRelease( p_sys->stream_id_spu, 0x20, p_stream->i_stream_id&0xff ); break; default: /* Never reached */ break; } if( p_input->p_fmt->i_cat == AUDIO_ES ) { p_sys->i_audio_bound--; } else if( p_input->p_fmt->i_cat == VIDEO_ES ) { p_sys->i_video_bound--; } /* Try to set a sensible default value for the instant bitrate */ p_sys->i_instant_bitrate -= (p_input->p_fmt->i_bitrate + 1000); /* rate_bound is in units of 50 bytes/second */ p_sys->i_rate_bound -= (p_input->p_fmt->i_bitrate * 2)/(8 * 50); p_sys->i_psm_version++; free( p_stream ); } /***************************************************************************** * Mux: Call each time there is new data for at least one stream *****************************************************************************/ static int Mux( sout_mux_t *p_mux ) { sout_mux_sys_t *p_sys = p_mux->p_sys; for( ;; ) { sout_input_t *p_input; ps_stream_t *p_stream; block_t *p_ps, *p_data; vlc_tick_t i_dts; /* Choose which stream to mux */ int i_stream = sout_MuxGetStream( p_mux, 1, &i_dts ); if( i_stream < 0 ) { return VLC_SUCCESS; } p_input = p_mux->pp_inputs[i_stream]; p_stream = (ps_stream_t*)p_input->p_sys; p_ps = NULL; /* Write regulary PackHeader */ if( p_sys->i_pes_count % 30 == 0) { /* Update the instant bitrate every second or so */ if( p_sys->i_instant_size && i_dts - p_sys->i_instant_dts > 1000000 ) { int64_t i_instant_bitrate = p_sys->i_instant_size * 8000000 / ( i_dts - p_sys->i_instant_dts ); p_sys->i_instant_bitrate += i_instant_bitrate; p_sys->i_instant_bitrate /= 2; p_sys->i_instant_size = 0; p_sys->i_instant_dts = i_dts; } else if( !p_sys->i_instant_size ) { p_sys->i_instant_dts = i_dts; } MuxWritePackHeader( p_mux, &p_ps, i_dts ); } /* Write regulary SystemHeader */ if( p_sys->i_pes_count % 300 == 0 ) { block_t *p_pk; MuxWriteSystemHeader( p_mux, &p_ps, i_dts ); /* For MPEG1 streaming, set HEADER flag */ for( p_pk = p_ps; p_pk != NULL; p_pk = p_pk->p_next ) { p_pk->i_flags |= BLOCK_FLAG_HEADER; } } /* Write regulary ProgramStreamMap */ if( p_sys->b_mpeg2 && p_sys->i_pes_count % 300 == 0 ) { MuxWritePSM( p_mux, &p_ps, i_dts ); } /* Get and mux a packet */ p_data = block_FifoGet( p_input->p_fifo ); EStoPES ( &p_data, p_input->p_fmt, p_stream->i_stream_id, p_sys->b_mpeg2, 0, 0, p_sys->i_pes_max_size, 0 ); block_ChainAppend( &p_ps, p_data ); /* Get size of output data so we can calculate the instant bitrate */ for( p_data = p_ps; p_data; p_data = p_data->p_next ) { p_sys->i_instant_size += p_data->i_buffer; } sout_AccessOutWrite( p_mux->p_access, p_ps ); /* Increase counter */ p_sys->i_pes_count++; } return VLC_SUCCESS; } /***************************************************************************** * *****************************************************************************/ static void StreamIdInit( bool *id, int i_range ) { int i; for( i = 0; i < i_range; i++ ) { id[i] = true; } } static int StreamIdGet( bool *id, int i_id_min, int i_id_max ) { int i; for( i = 0; i <= i_id_max - i_id_min; i++ ) { if( id[i] ) { id[i] = false; return i_id_min + i; } } return -1; } static void StreamIdRelease( bool *id, int i_id_min, int i_id ) { id[i_id - i_id_min] = true; } static void MuxWritePackHeader( sout_mux_t *p_mux, block_t **p_buf, vlc_tick_t i_dts ) { sout_mux_sys_t *p_sys = p_mux->p_sys; bits_buffer_t bits; block_t *p_hdr; vlc_tick_t i_scr; int i_mux_rate; i_scr = (i_dts - p_sys->i_dts_delay) * 9 / 100; p_hdr = block_Alloc( 18 ); if( !p_hdr ) return; p_hdr->i_pts = p_hdr->i_dts = i_dts; bits_initwrite( &bits, 14, p_hdr->p_buffer ); bits_write( &bits, 32, 0x01ba ); /* The spec specifies that the mux rate must be rounded upwards */ i_mux_rate = (p_sys->i_instant_bitrate + 8 * 50 - 1 ) / (8 * 50); if( p_sys->b_mpeg2 ) { bits_write( &bits, 2, 0x01 ); } else { bits_write( &bits, 4, 0x02 ); } bits_write( &bits, 3, ( i_scr >> 30 )&0x07 ); bits_write( &bits, 1, 1 ); // marker bits_write( &bits, 15, ( i_scr >> 15 )&0x7fff ); bits_write( &bits, 1, 1 ); // marker bits_write( &bits, 15, i_scr&0x7fff ); bits_write( &bits, 1, 1 ); // marker if( p_sys->b_mpeg2 ) { bits_write( &bits, 9, 0 ); // src extension } bits_write( &bits, 1, 1 ); // marker bits_write( &bits, 22, i_mux_rate); bits_write( &bits, 1, 1 ); // marker if( p_sys->b_mpeg2 ) { bits_write( &bits, 1, 1 ); // marker bits_write( &bits, 5, 0x1f ); // reserved bits_write( &bits, 3, 0 ); // stuffing bytes } p_hdr->i_buffer = p_sys->b_mpeg2 ? 14: 12; block_ChainAppend( p_buf, p_hdr ); } static void MuxWriteSystemHeader( sout_mux_t *p_mux, block_t **p_buf, vlc_tick_t i_dts ) { sout_mux_sys_t *p_sys = p_mux->p_sys; block_t *p_hdr; bits_buffer_t bits; bool b_private; int i_rate_bound; int i_nb_private, i_nb_stream; int i; /* Count the number of private stream */ for( i = 0, i_nb_private = 0; i < p_mux->i_nb_inputs; i++ ) { ps_stream_t *p_stream; p_stream = (ps_stream_t*)p_mux->pp_inputs[i]->p_sys; if( ( p_stream->i_stream_id&0xff00 ) == 0xbd00 ) { i_nb_private++; } } /* Private stream are declared only one time */ i_nb_stream = p_mux->i_nb_inputs - ( i_nb_private > 0 ? i_nb_private - 1 : 0 ); p_hdr = block_Alloc( 12 + i_nb_stream * 3 ); if( !p_hdr ) return; p_hdr->i_dts = p_hdr->i_pts = i_dts; /* The spec specifies that the reported rate_bound must be upper limit */ i_rate_bound = (p_sys->i_rate_bound); bits_initwrite( &bits, 12 + i_nb_stream * 3, p_hdr->p_buffer ); bits_write( &bits, 32, 0x01bb ); bits_write( &bits, 16, 12 - 6 + i_nb_stream * 3 ); bits_write( &bits, 1, 1 ); // marker bit bits_write( &bits, 22, i_rate_bound); bits_write( &bits, 1, 1 ); // marker bit bits_write( &bits, 6, p_sys->i_audio_bound ); bits_write( &bits, 1, 0 ); // fixed flag bits_write( &bits, 1, 0 ); // CSPS flag bits_write( &bits, 1, 0 ); // system audio lock flag bits_write( &bits, 1, 0 ); // system video lock flag bits_write( &bits, 1, 1 ); // marker bit bits_write( &bits, 5, p_sys->i_video_bound ); bits_write( &bits, 1, 1 ); // packet rate restriction flag (1 for mpeg1) bits_write( &bits, 7, 0xff ); // reserved bits /* stream_id table */ for( i = 0, b_private = false; i < p_mux->i_nb_inputs; i++ ) { sout_input_t *p_input; ps_stream_t *p_stream; p_input = p_mux->pp_inputs[i]; p_stream = (ps_stream_t *)p_input->p_sys; if( ( p_stream->i_stream_id&0xff00 ) == 0xbd00 ) { if( b_private ) { continue; } b_private = true; /* Write stream id */ bits_write( &bits, 8, 0xbd ); } else { /* Write stream id */ bits_write( &bits, 8, p_stream->i_stream_id&0xff ); } bits_write( &bits, 2, 0x03 ); /* reserved */ if( p_input->p_fmt->i_cat == AUDIO_ES ) { bits_write( &bits, 1, 0 ); bits_write( &bits, 13, p_stream->i_max_buff_size / 128 ); } else if( p_input->p_fmt->i_cat == VIDEO_ES ) { bits_write( &bits, 1, 1 ); bits_write( &bits, 13, p_stream->i_max_buff_size / 1024); } else { /* FIXME -- the scale of 0 means do a /128 */ bits_write( &bits, 1, 0 ); bits_write( &bits, 13, p_stream->i_max_buff_size / 128 ); } } block_ChainAppend( p_buf, p_hdr ); } static void MuxWritePSM( sout_mux_t *p_mux, block_t **p_buf, vlc_tick_t i_dts ) { sout_mux_sys_t *p_sys = p_mux->p_sys; block_t *p_hdr; bits_buffer_t bits; int i, i_psm_size = 16, i_es_map_size = 0; for( i = 0; i < p_mux->i_nb_inputs; i++ ) { sout_input_t *p_input = p_mux->pp_inputs[i]; ps_stream_t *p_stream = p_input->p_sys; i_es_map_size += 4; if( p_stream->lang[0] != 0 ) i_es_map_size += 6; } i_psm_size += i_es_map_size; p_hdr = block_Alloc( i_psm_size ); if( !p_hdr ) return; p_hdr->i_dts = p_hdr->i_pts = i_dts; memset( p_hdr->p_buffer, 0, p_hdr->i_buffer ); bits_initwrite( &bits, i_psm_size, p_hdr->p_buffer ); bits_write( &bits, 32, 0x01bc ); bits_write( &bits, 16, i_psm_size - 6 ); bits_write( &bits, 1, 1 ); /* current_next_indicator */ bits_write( &bits, 2, 0xF ); /* reserved */ bits_write( &bits, 5, p_sys->i_psm_version ); bits_write( &bits, 7, 0xFF ); /* reserved */ bits_write( &bits, 1, 1 ); /* marker */ bits_write( &bits, 16, 0 ); /* program_stream_info_length */ /* empty */ bits_write( &bits, 16, i_es_map_size ); /* elementary_stream_map_length */ for( i = 0; i < p_mux->i_nb_inputs; i++ ) { sout_input_t *p_input = p_mux->pp_inputs[i]; ps_stream_t *p_stream = p_input->p_sys; bits_write( &bits, 8, p_stream->i_stream_type ); /* stream_type */ bits_write( &bits, 8, p_stream->i_stream_id ); /* elementary_stream_id */ /* ISO639 language descriptor */ if( p_stream->lang[0] != 0 ) { bits_write( &bits, 16, 6 ); /* elementary_stream_info_length */ bits_write( &bits, 8, 0x0a ); /* descriptor_tag */ bits_write( &bits, 8, 4 ); /* descriptor_length */ bits_write( &bits, 8, p_stream->lang[0] ); bits_write( &bits, 8, p_stream->lang[1] ); bits_write( &bits, 8, p_stream->lang[2] ); bits_write( &bits, 8, 0 ); /* audio type: 0x00 undefined */ } else { bits_write( &bits, 16, 0 ); /* elementary_stream_info_length */ } } /* CRC32 */ { uint32_t i_crc = 0xffffffff; for( i = 0; (size_t)i < p_hdr->i_buffer; i++ ) i_crc = (i_crc << 8) ^ p_sys->crc32_table[((i_crc >> 24) ^ p_hdr->p_buffer[i]) & 0xff]; bits_write( &bits, 32, i_crc ); } block_ChainAppend( p_buf, p_hdr ); }