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 *****************************************************************************/
27 #include <stdlib.h> /* malloc(), free() */
30 #include <vlc_demux.h>
31 #include "vlc_codec.h"
33 /*****************************************************************************
35 *****************************************************************************/
36 static int Open ( vlc_object_t * );
37 static void Close( vlc_object_t * );
40 set_category( CAT_INPUT );
41 set_subcategory( SUBCAT_INPUT_DEMUX );
42 set_description( _("MPEG-4 audio demuxer" ) );
43 set_capability( "demux2", 110 );
44 set_callbacks( Open, Close );
45 add_shortcut( "m4a" );
46 add_shortcut( "mp4a" );
47 add_shortcut( "aac" );
50 /*****************************************************************************
52 *****************************************************************************/
58 decoder_t *p_packetizer;
62 mtime_t i_time_offset;
66 static int Demux( demux_t * );
67 static int Control( demux_t *, int, va_list );
69 #define M4A_PACKET_SIZE 4096
70 #define M4A_PTS_START 1
72 /*****************************************************************************
73 * Open: initializes demux structures
74 *****************************************************************************/
75 static int Open( vlc_object_t * p_this )
77 demux_t *p_demux = (demux_t*)p_this;
80 int b_forced = VLC_FALSE;
82 if( p_demux->psz_path )
84 int i_len = strlen( p_demux->psz_path );
86 if( i_len > 4 && !strcasecmp( &p_demux->psz_path[i_len - 4], ".aac" ) )
92 if( !p_demux->b_force && !b_forced )
97 /* peek the begining (10 is for adts header) */
98 if( stream_Peek( p_demux->s, &p_peek, 10 ) < 10 )
100 msg_Err( p_demux, "cannot peek" );
103 if( !strncmp( (char *)p_peek, "ADIF", 4 ) )
105 msg_Err( p_demux, "ADIF file. Not yet supported. (Please report)" );
109 p_demux->pf_demux = Demux;
110 p_demux->pf_control= Control;
111 p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
113 p_sys->b_start = VLC_TRUE;
116 p_sys->i_time_offset = 0;
117 p_sys->i_bitrate_avg = 0;
119 /* Load the mpeg 4 audio packetizer */
120 INIT_APACKETIZER( p_sys->p_packetizer, 'm', 'p', '4', 'a' );
121 es_format_Init( &p_sys->p_packetizer->fmt_out, UNKNOWN_ES, 0 );
122 LOAD_PACKETIZER_OR_FAIL( p_sys->p_packetizer, "mp4 audio" );
127 /*****************************************************************************
128 * Close: frees unused data
129 *****************************************************************************/
130 static void Close( vlc_object_t * p_this )
132 demux_t *p_demux = (demux_t*)p_this;
133 demux_sys_t *p_sys = p_demux->p_sys;
135 DESTROY_PACKETIZER( p_sys->p_packetizer );
140 /*****************************************************************************
141 * Demux: reads and demuxes data packets
142 *****************************************************************************
143 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
144 *****************************************************************************/
145 static int Demux( demux_t *p_demux)
147 demux_sys_t *p_sys = p_demux->p_sys;
148 block_t *p_block_in, *p_block_out;
150 if( ( p_block_in = stream_Block( p_demux->s, M4A_PACKET_SIZE ) ) == NULL )
155 p_block_in->i_pts = p_block_in->i_dts = p_sys->b_start ? M4A_PTS_START : 0;
156 p_sys->b_start = VLC_FALSE;
158 while( (p_block_out = p_sys->p_packetizer->pf_packetize(
159 p_sys->p_packetizer, &p_block_in )) )
163 block_t *p_next = p_block_out->p_next;
165 if( p_sys->p_es == NULL )
167 p_sys->p_packetizer->fmt_out.b_packetized = VLC_TRUE;
168 p_sys->p_es = es_out_Add( p_demux->out,
169 &p_sys->p_packetizer->fmt_out);
172 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block_out->i_dts );
174 p_block_out->p_next = NULL;
176 p_sys->i_pts = p_block_out->i_pts;
177 if( p_sys->i_pts > M4A_PTS_START + I64C(500000) )
178 p_sys->i_bitrate_avg =
179 8*I64C(1000000)*p_sys->i_bytes/(p_sys->i_pts-M4A_PTS_START);
181 p_sys->i_bytes += p_block_out->i_buffer;
182 es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
184 p_block_out = p_next;
190 /*****************************************************************************
192 *****************************************************************************/
193 static int Control( demux_t *p_demux, int i_query, va_list args )
195 demux_sys_t *p_sys = p_demux->p_sys;
202 pi64 = (int64_t*)va_arg( args, int64_t * );
203 *pi64 = p_sys->i_pts + p_sys->i_time_offset;
206 case DEMUX_SET_TIME: /* TODO high precision seek for multi-input */
208 i_ret = demux2_vaControlHelper( p_demux->s, 0, -1,
209 p_sys->i_bitrate_avg, 1, i_query, args);
210 /* Fix time_offset */
211 if( (i_query == DEMUX_SET_POSITION || i_query == DEMUX_SET_TIME ) &&
212 i_ret == VLC_SUCCESS && p_sys->i_bitrate_avg > 0 )
214 int64_t i_time = I64C(8000000) * stream_Tell(p_demux->s) /
215 p_sys->i_bitrate_avg;
218 p_sys->i_time_offset = i_time - p_sys->i_pts;