1 /*****************************************************************************
2 * m4a.c : MPEG-4 audio demuxer
3 *****************************************************************************
4 * Copyright (C) 2002-2004 the VideoLAN team
7 * Authors: Gildas Bazin <gbazin@videolan.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
33 #include <vlc_demux.h>
34 #include <vlc_codec.h>
35 #include <vlc_input.h>
37 /*****************************************************************************
39 *****************************************************************************/
40 static int Open ( vlc_object_t * );
41 static void Close( vlc_object_t * );
44 set_category( CAT_INPUT );
45 set_subcategory( SUBCAT_INPUT_DEMUX );
46 set_description( _("MPEG-4 audio demuxer" ) );
47 set_capability( "demux", 110 );
48 set_callbacks( Open, Close );
49 add_shortcut( "m4a" );
50 add_shortcut( "mp4a" );
51 add_shortcut( "aac" );
54 /*****************************************************************************
56 *****************************************************************************/
62 decoder_t *p_packetizer;
66 mtime_t i_time_offset;
70 static int Demux( demux_t * );
71 static int Control( demux_t *, int, va_list );
73 #define M4A_PACKET_SIZE 4096
74 #define M4A_PTS_START 1
76 /*****************************************************************************
77 * Open: initializes demux structures
78 *****************************************************************************/
79 static int Open( vlc_object_t * p_this )
81 demux_t *p_demux = (demux_t*)p_this;
83 const uint8_t *p_peek;
86 if( demux_IsPathExtension( p_demux, ".aac" ) )
89 if( !p_demux->b_force && !b_forced )
92 /* peek the begining (10 is for adts header) */
93 if( stream_Peek( p_demux->s, &p_peek, 10 ) < 10 )
95 msg_Err( p_demux, "cannot peek" );
98 if( !strncmp( (char *)p_peek, "ADIF", 4 ) )
100 msg_Err( p_demux, "ADIF file. Not yet supported. (Please report)" );
104 p_demux->pf_demux = Demux;
105 p_demux->pf_control= Control;
106 p_demux->p_sys = p_sys = calloc( sizeof( demux_sys_t ), 1 );
107 p_sys->b_start = true;
109 /* Load the mpeg 4 audio packetizer */
110 INIT_APACKETIZER( p_sys->p_packetizer, 'm', 'p', '4', 'a' );
111 es_format_Init( &p_sys->p_packetizer->fmt_out, UNKNOWN_ES, 0 );
112 LOAD_PACKETIZER_OR_FAIL( p_sys->p_packetizer, "mp4 audio" );
117 /*****************************************************************************
118 * Close: frees unused data
119 *****************************************************************************/
120 static void Close( vlc_object_t * p_this )
122 demux_t *p_demux = (demux_t*)p_this;
123 demux_sys_t *p_sys = p_demux->p_sys;
125 DESTROY_PACKETIZER( p_sys->p_packetizer );
130 /*****************************************************************************
131 * Demux: reads and demuxes data packets
132 *****************************************************************************
133 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
134 *****************************************************************************/
135 static int Demux( demux_t *p_demux)
137 demux_sys_t *p_sys = p_demux->p_sys;
138 block_t *p_block_in, *p_block_out;
140 if( ( p_block_in = stream_Block( p_demux->s, M4A_PACKET_SIZE ) ) == NULL )
145 p_block_in->i_pts = p_block_in->i_dts = p_sys->b_start ? M4A_PTS_START : 0;
146 p_sys->b_start = false;
148 while( (p_block_out = p_sys->p_packetizer->pf_packetize(
149 p_sys->p_packetizer, &p_block_in )) )
153 block_t *p_next = p_block_out->p_next;
155 if( p_sys->p_es == NULL )
157 p_sys->p_packetizer->fmt_out.b_packetized = true;
158 p_sys->p_es = es_out_Add( p_demux->out,
159 &p_sys->p_packetizer->fmt_out);
162 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
164 p_block_out->p_next = NULL;
166 p_sys->i_pts = p_block_out->i_pts;
167 if( p_sys->i_pts > M4A_PTS_START + I64C(500000) )
168 p_sys->i_bitrate_avg =
169 8*I64C(1000000)*p_sys->i_bytes/(p_sys->i_pts-M4A_PTS_START);
171 p_sys->i_bytes += p_block_out->i_buffer;
172 es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
174 p_block_out = p_next;
180 /*****************************************************************************
182 *****************************************************************************/
183 static int Control( demux_t *p_demux, int i_query, va_list args )
185 demux_sys_t *p_sys = p_demux->p_sys;
192 case DEMUX_HAS_UNSUPPORTED_META:
193 pb_bool = (bool *)va_arg( args, bool* );
198 pi64 = (int64_t*)va_arg( args, int64_t * );
199 *pi64 = p_sys->i_pts + p_sys->i_time_offset;
202 case DEMUX_SET_TIME: /* TODO high precision seek for multi-input */
204 i_ret = demux_vaControlHelper( p_demux->s, 0, -1,
205 p_sys->i_bitrate_avg, 1, i_query, args);
206 /* Fix time_offset */
207 if( (i_query == DEMUX_SET_POSITION || i_query == DEMUX_SET_TIME ) &&
208 i_ret == VLC_SUCCESS && p_sys->i_bitrate_avg > 0 )
210 int64_t i_time = I64C(8000000) * stream_Tell(p_demux->s) /
211 p_sys->i_bitrate_avg;
214 p_sys->i_time_offset = i_time - p_sys->i_pts;