1 /*****************************************************************************
2 * dtstospdif.c : encapsulates DTS frames into S/PDIF packets
3 *****************************************************************************
4 * Copyright (C) 2003, 2006 the VideoLAN team
7 * Authors: Jon Lech Johansen <jon-vl@nanocrew.net>
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() */
36 #include "audio_output.h"
37 #include "aout_internal.h"
39 /*****************************************************************************
41 *****************************************************************************/
42 struct aout_filter_sys_t
44 /* 3 DTS frames have to be packed into an S/PDIF frame.
45 * We accumulate DTS frames from the decoder until we have enough to
53 unsigned int i_frame_size;
56 /*****************************************************************************
58 *****************************************************************************/
59 static int Create ( vlc_object_t * );
60 static void Close ( vlc_object_t * );
61 static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
64 /*****************************************************************************
66 *****************************************************************************/
68 set_category( CAT_AUDIO );
69 set_subcategory( SUBCAT_AUDIO_MISC );
70 set_description( _("Audio filter for DTS->S/PDIF encapsulation") );
71 set_capability( "audio filter", 10 );
72 set_callbacks( Create, Close );
75 /*****************************************************************************
77 *****************************************************************************/
78 static int Create( vlc_object_t *p_this )
80 aout_filter_t * p_filter = (aout_filter_t *)p_this;
82 if( p_filter->input.i_format != VLC_FOURCC('d','t','s',' ') ||
83 ( p_filter->output.i_format != VLC_FOURCC('s','p','d','i') &&
84 p_filter->output.i_format != VLC_FOURCC('s','p','d','b') ) )
89 /* Allocate the memory needed to store the module's structure */
90 p_filter->p_sys = malloc( sizeof(struct aout_filter_sys_t) );
91 if( p_filter->p_sys == NULL )
93 msg_Err( p_filter, "out of memory" );
96 memset( p_filter->p_sys, 0, sizeof(struct aout_filter_sys_t) );
97 p_filter->p_sys->p_buf = 0;
99 p_filter->pf_do_work = DoWork;
100 p_filter->b_in_place = 1;
105 /*****************************************************************************
106 * Close: free our resources
107 *****************************************************************************/
108 static void Close( vlc_object_t * p_this )
110 aout_filter_t * p_filter = (aout_filter_t *)p_this;
111 if( p_filter->p_sys->i_frame_size ) free( p_filter->p_sys->p_buf );
112 free( p_filter->p_sys );
115 /*****************************************************************************
116 * DoWork: convert a buffer
117 *****************************************************************************/
118 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
119 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
121 uint32_t i_ac5_spdif_type = 0;
122 uint16_t i_fz = p_in_buf->i_nb_samples * 4;
123 uint16_t i_frame, i_length = p_in_buf->i_nb_bytes;
124 static const uint8_t p_sync_le[6] = { 0x72, 0xF8, 0x1F, 0x4E, 0x00, 0x00 };
125 static const uint8_t p_sync_be[6] = { 0xF8, 0x72, 0x4E, 0x1F, 0x00, 0x00 };
127 if( p_in_buf->i_nb_bytes != p_filter->p_sys->i_frame_size )
129 /* Frame size changed, reset everything */
130 p_filter->p_sys->i_frame_size = p_in_buf->i_nb_bytes;
131 p_filter->p_sys->p_buf = realloc( p_filter->p_sys->p_buf,
132 p_in_buf->i_nb_bytes * 3 );
133 p_filter->p_sys->i_frames = 0;
137 p_filter->p_vlc->pf_memcpy( p_filter->p_sys->p_buf + p_in_buf->i_nb_bytes *
138 p_filter->p_sys->i_frames, p_in_buf->p_buffer,
139 p_in_buf->i_nb_bytes );
141 p_filter->p_sys->i_frames++;
143 if( p_filter->p_sys->i_frames < 3 )
145 if( !p_filter->p_sys->i_frames )
146 /* We'll need the starting date */
147 p_filter->p_sys->start_date = p_in_buf->start_date;
149 /* Not enough data */
150 p_out_buf->i_nb_samples = 0;
151 p_out_buf->i_nb_bytes = 0;
155 p_filter->p_sys->i_frames = 0;
157 for( i_frame = 0; i_frame < 3; i_frame++ )
159 byte_t * p_out = p_out_buf->p_buffer + (i_frame * i_fz);
160 byte_t * p_in = p_filter->p_sys->p_buf + (i_frame * i_length);
162 switch( p_in_buf->i_nb_samples )
164 case 512: i_ac5_spdif_type = 0x0B; break;
165 case 1024: i_ac5_spdif_type = 0x0C; break;
166 case 2048: i_ac5_spdif_type = 0x0D; break;
169 /* Copy the S/PDIF headers. */
170 if( p_filter->output.i_format == VLC_FOURCC('s','p','d','b') )
172 p_filter->p_vlc->pf_memcpy( p_out, p_sync_be, 6 );
173 p_out[5] = i_ac5_spdif_type;
174 p_out[6] = (( i_length ) >> 5 ) & 0xFF;
175 p_out[7] = ( i_length << 3 ) & 0xFF;
179 p_filter->p_vlc->pf_memcpy( p_out, p_sync_le, 6 );
180 p_out[4] = i_ac5_spdif_type;
181 p_out[6] = ( i_length << 3 ) & 0xFF;
182 p_out[7] = (( i_length ) >> 5 ) & 0xFF;
185 if( ( (p_in[0] == 0x1F || p_in[0] == 0x7F) && p_filter->output.i_format == VLC_FOURCC('s','p','d','i') ) ||
186 ( (p_in[0] == 0xFF || p_in[0] == 0xFE) && p_filter->output.i_format == VLC_FOURCC('s','p','d','b') ) )
188 /* We are dealing with a big endian bitstream and a little endian output
189 * or a little endian bitstream and a big endian output.
190 * Byteswap the stream */
192 swab( p_in, p_out + 8, i_length );
197 for( i = i_length / 2 ; i-- ; )
199 tmp = p_in[0]; /* in-place filter */
202 p_tmp += 2; p_in += 2;
208 p_filter->p_vlc->pf_memcpy( p_out + 8, p_in, i_length );
211 if( i_fz > i_length + 8 )
213 p_filter->p_vlc->pf_memset( p_out + 8 + i_length, 0,
214 i_fz - i_length - 8 );
218 p_out_buf->start_date = p_filter->p_sys->start_date;
219 p_out_buf->i_nb_samples = p_in_buf->i_nb_samples * 3;
220 p_out_buf->i_nb_bytes = p_out_buf->i_nb_samples * 4;