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 *****************************************************************************/
40 /*****************************************************************************
42 *****************************************************************************/
43 struct aout_filter_sys_t
45 /* 3 DTS frames have to be packed into an S/PDIF frame.
46 * We accumulate DTS frames from the decoder until we have enough to
54 unsigned int i_frame_size;
57 /*****************************************************************************
59 *****************************************************************************/
60 static int Create ( vlc_object_t * );
61 static void Close ( vlc_object_t * );
62 static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
65 /*****************************************************************************
67 *****************************************************************************/
69 set_category( CAT_AUDIO );
70 set_subcategory( SUBCAT_AUDIO_MISC );
71 set_description( _("Audio filter for DTS->S/PDIF encapsulation") );
72 set_capability( "audio filter", 10 );
73 set_callbacks( Create, Close );
76 /*****************************************************************************
78 *****************************************************************************/
79 static int Create( vlc_object_t *p_this )
81 aout_filter_t * p_filter = (aout_filter_t *)p_this;
83 if( p_filter->input.i_format != VLC_FOURCC('d','t','s',' ') ||
84 ( p_filter->output.i_format != VLC_FOURCC('s','p','d','i') &&
85 p_filter->output.i_format != VLC_FOURCC('s','p','d','b') ) )
90 /* Allocate the memory needed to store the module's structure */
91 p_filter->p_sys = malloc( sizeof(struct aout_filter_sys_t) );
92 if( p_filter->p_sys == NULL )
94 msg_Err( p_filter, "out of memory" );
97 memset( p_filter->p_sys, 0, sizeof(struct aout_filter_sys_t) );
98 p_filter->p_sys->p_buf = 0;
100 p_filter->pf_do_work = DoWork;
101 p_filter->b_in_place = 1;
106 /*****************************************************************************
107 * Close: free our resources
108 *****************************************************************************/
109 static void Close( vlc_object_t * p_this )
111 aout_filter_t * p_filter = (aout_filter_t *)p_this;
112 if( p_filter->p_sys->i_frame_size ) free( p_filter->p_sys->p_buf );
113 free( p_filter->p_sys );
116 /*****************************************************************************
117 * DoWork: convert a buffer
118 *****************************************************************************/
119 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
120 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
122 uint32_t i_ac5_spdif_type = 0;
123 uint16_t i_fz = p_in_buf->i_nb_samples * 4;
124 uint16_t i_frame, i_length = p_in_buf->i_nb_bytes;
125 static const uint8_t p_sync_le[6] = { 0x72, 0xF8, 0x1F, 0x4E, 0x00, 0x00 };
126 static const uint8_t p_sync_be[6] = { 0xF8, 0x72, 0x4E, 0x1F, 0x00, 0x00 };
128 if( p_in_buf->i_nb_bytes != p_filter->p_sys->i_frame_size )
130 /* Frame size changed, reset everything */
131 msg_Warn( p_aout, "Frame size changed from %d to %d, resetting everything.",
132 p_filter->p_sys->i_frame_size, p_in_buf->i_nb_bytes );
134 p_filter->p_sys->i_frame_size = p_in_buf->i_nb_bytes;
135 p_filter->p_sys->p_buf = realloc( p_filter->p_sys->p_buf,
136 p_in_buf->i_nb_bytes * 3 );
137 p_filter->p_sys->i_frames = 0;
141 vlc_memcpy( p_filter->p_sys->p_buf + p_in_buf->i_nb_bytes *
142 p_filter->p_sys->i_frames,
143 p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
145 p_filter->p_sys->i_frames++;
147 if( p_filter->p_sys->i_frames < 3 )
149 if( p_filter->p_sys->i_frames == 1 )
150 /* We'll need the starting date */
151 p_filter->p_sys->start_date = p_in_buf->start_date;
153 /* Not enough data */
154 p_out_buf->i_nb_samples = 0;
155 p_out_buf->i_nb_bytes = 0;
159 p_filter->p_sys->i_frames = 0;
161 for( i_frame = 0; i_frame < 3; i_frame++ )
163 uint16_t i_length_padded = i_length;
164 uint8_t * p_out = p_out_buf->p_buffer + (i_frame * i_fz);
165 uint8_t * p_in = p_filter->p_sys->p_buf + (i_frame * i_length);
167 switch( p_in_buf->i_nb_samples )
169 case 512: i_ac5_spdif_type = 0x0B; break;
170 case 1024: i_ac5_spdif_type = 0x0C; break;
171 case 2048: i_ac5_spdif_type = 0x0D; break;
174 /* Copy the S/PDIF headers. */
175 if( p_filter->output.i_format == VLC_FOURCC('s','p','d','b') )
177 vlc_memcpy( p_out, p_sync_be, 6 );
178 p_out[5] = i_ac5_spdif_type;
179 p_out[6] = (( i_length ) >> 5 ) & 0xFF;
180 p_out[7] = ( i_length << 3 ) & 0xFF;
184 vlc_memcpy( p_out, p_sync_le, 6 );
185 p_out[4] = i_ac5_spdif_type;
186 p_out[6] = ( i_length << 3 ) & 0xFF;
187 p_out[7] = (( i_length ) >> 5 ) & 0xFF;
190 if( ( (p_in[0] == 0x1F || p_in[0] == 0x7F) && p_filter->output.i_format == VLC_FOURCC('s','p','d','i') ) ||
191 ( (p_in[0] == 0xFF || p_in[0] == 0xFE) && p_filter->output.i_format == VLC_FOURCC('s','p','d','b') ) )
193 /* We are dealing with a big endian bitstream and a little endian output
194 * or a little endian bitstream and a big endian output.
195 * Byteswap the stream */
197 swab( p_in, p_out + 8, i_length );
200 uint8_t * p_tmp, tmp;
202 for( i = i_length / 2 ; i-- ; )
204 tmp = p_in[0]; /* in-place filter */
207 p_tmp += 2; p_in += 2;
210 /* If i_length is odd, we have to adjust swapping a bit.. */
213 p_out[8+i_length-1] = 0;
214 p_out[8+i_length] = p_in[i_length-1];
220 vlc_memcpy( p_out + 8, p_in, i_length );
223 if( i_fz > i_length + 8 )
225 vlc_memset( p_out + 8 + i_length_padded, 0,
226 i_fz - i_length_padded - 8 );
230 p_out_buf->start_date = p_filter->p_sys->start_date;
231 p_out_buf->i_nb_samples = p_in_buf->i_nb_samples * 3;
232 p_out_buf->i_nb_bytes = p_out_buf->i_nb_samples * 4;