1 /*****************************************************************************
2 * xa.c : xa file demux module for vlc
3 *****************************************************************************
4 * Copyright (C) 2005 Rémi Denis-Courmont
7 * Authors: Rémi Denis-Courmont <rem # 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 *****************************************************************************/
32 #include <vlc_common.h>
33 #include <vlc_plugin.h>
34 #include <vlc_demux.h>
36 /*****************************************************************************
38 *****************************************************************************/
39 static int Open ( vlc_object_t * );
40 static void Close( vlc_object_t * );
43 set_description( N_("XA demuxer") )
44 set_category( CAT_INPUT )
45 set_subcategory( SUBCAT_INPUT_DEMUX )
46 set_capability( "demux", 10 )
47 set_callbacks( Open, Close )
50 /*****************************************************************************
52 *****************************************************************************/
53 static int Demux ( demux_t * );
54 static int Control( demux_t *, int i_query, va_list args );
61 int64_t i_data_offset;
62 unsigned int i_data_size;
63 unsigned int i_block_frames;
68 typedef struct xa_header_t
75 uint32_t nSamplesPerSec;
76 uint32_t nAvgBytesPerSec;
78 uint16_t wBitsPerSample;
81 /*****************************************************************************
82 * Open: check file and initializes structures
83 *****************************************************************************/
84 static int Open( vlc_object_t * p_this )
86 demux_t *p_demux = (demux_t*)p_this;
91 /* XA file heuristic */
92 if( stream_Peek( p_demux->s, &p_buf, sizeof( p_xa ) )
93 < (signed)sizeof( p_xa ) )
96 memcpy( &p_xa, p_buf, sizeof( p_xa ) );
97 if( ( strncmp( p_xa.xa_id, "XAI", 4 )
98 && strncmp( p_xa.xa_id, "XAJ", 4 ) )
99 || ( GetWLE( &p_xa.wFormatTag ) != 0x0001)
100 || ( GetWLE( &p_xa.wBitsPerSample ) != 16) )
103 p_sys = malloc( sizeof( demux_sys_t ) );
104 if( unlikely( p_sys == NULL ) )
107 p_demux->pf_demux = Demux;
108 p_demux->pf_control = Control;
109 p_demux->p_sys = p_sys;
112 /* skip XA header -- cannot fail */
113 stream_Read( p_demux->s, NULL, sizeof( p_xa ) );
115 es_format_Init( &p_sys->fmt, AUDIO_ES, VLC_FOURCC('X','A','J',0) );
117 msg_Dbg( p_demux, "assuming EA ADPCM audio codec" );
118 p_sys->fmt.audio.i_rate = GetDWLE( &p_xa.nSamplesPerSec );
119 p_sys->fmt.audio.i_bytes_per_frame = 15 * GetWLE( &p_xa.nChannels );
120 p_sys->fmt.audio.i_frame_length = 28; /* 28 samples of 4 bits each */
122 p_sys->fmt.audio.i_channels = GetWLE ( &p_xa.nChannels );
123 p_sys->fmt.audio.i_blockalign = p_sys->fmt.audio.i_bytes_per_frame;
124 p_sys->fmt.audio.i_bitspersample = 16;
125 p_sys->fmt.i_bitrate = (p_sys->fmt.audio.i_rate
126 * p_sys->fmt.audio.i_bytes_per_frame * 8)
127 / p_sys->fmt.audio.i_frame_length;
128 p_sys->fmt.i_extra = 0;
129 p_sys->fmt.p_extra = NULL;
131 p_sys->i_data_offset = stream_Tell( p_demux->s );
132 /* FIXME: better computation */
133 p_sys->i_data_size = p_xa.iSize * 15 / 56;
134 /* How many frames per block (1:1 is too CPU intensive) */
135 p_sys->i_block_frames = p_sys->fmt.audio.i_rate / (28 * 20) + 1;
137 msg_Dbg( p_demux, "fourcc: %4.4s, channels: %d, "
138 "freq: %d Hz, bitrate: %dKo/s, blockalign: %d",
139 (char *)&p_sys->fmt.i_codec, p_sys->fmt.audio.i_channels,
140 p_sys->fmt.audio.i_rate, p_sys->fmt.i_bitrate / 8192,
141 p_sys->fmt.audio.i_blockalign );
143 p_sys->p_es = es_out_Add( p_demux->out, &p_sys->fmt );
145 date_Init( &p_sys->pts, p_sys->fmt.audio.i_rate, 1 );
146 date_Set( &p_sys->pts, 1 );
151 /*****************************************************************************
152 * Demux: read packet and send them to decoders
153 *****************************************************************************
154 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
155 *****************************************************************************/
156 static int Demux( demux_t *p_demux )
158 demux_sys_t *p_sys = p_demux->p_sys;
161 unsigned i_frames = p_sys->i_block_frames;
163 i_offset = stream_Tell( p_demux->s );
165 if( p_sys->i_data_size > 0 &&
166 i_offset >= p_sys->i_data_offset + p_sys->i_data_size )
172 p_block = stream_Block( p_demux->s, p_sys->fmt.audio.i_bytes_per_frame *
174 if( p_block == NULL )
176 msg_Warn( p_demux, "cannot read data" );
180 i_frames = p_block->i_buffer / p_sys->fmt.audio.i_bytes_per_frame;
181 p_block->i_dts = p_block->i_pts = VLC_TS_0 + date_Get( &p_sys->pts );
182 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block->i_pts );
183 es_out_Send( p_demux->out, p_sys->p_es, p_block );
185 date_Increment( &p_sys->pts, i_frames * p_sys->fmt.audio.i_frame_length );
190 /*****************************************************************************
191 * Close: frees unused data
192 *****************************************************************************/
193 static void Close ( vlc_object_t * p_this )
195 demux_sys_t *p_sys = ((demux_t *)p_this)->p_sys;
200 /*****************************************************************************
202 *****************************************************************************/
203 static int Control( demux_t *p_demux, int i_query, va_list args )
205 demux_sys_t *p_sys = p_demux->p_sys;
207 return demux_vaControlHelper( p_demux->s, p_sys->i_data_offset,
208 p_sys->i_data_size ? p_sys->i_data_offset
209 + p_sys->i_data_size : -1,
210 p_sys->fmt.i_bitrate,
211 p_sys->fmt.audio.i_blockalign,