1 /*****************************************************************************
2 * trivial.c : trivial mixer plug-in (1 input, no downmixing)
3 *****************************************************************************
4 * Copyright (C) 2002 the VideoLAN team
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
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_common.h>
34 #include <vlc_plugin.h>
37 /*****************************************************************************
39 *****************************************************************************/
40 static int Create ( vlc_object_t * );
42 static void DoWork ( aout_mixer_t *, aout_buffer_t * );
44 /*****************************************************************************
46 *****************************************************************************/
48 set_category( CAT_AUDIO )
49 set_subcategory( SUBCAT_AUDIO_MISC )
50 set_description( N_("Trivial audio mixer") )
51 set_capability( "audio mixer", 1 )
52 set_callbacks( Create, NULL )
55 /*****************************************************************************
56 * Create: allocate trivial mixer
57 *****************************************************************************/
58 static int Create( vlc_object_t *p_this )
60 aout_mixer_t *p_mixer = (aout_mixer_t *)p_this;
62 if ( p_mixer->fmt.i_format != VLC_CODEC_FL32
63 && p_mixer->fmt.i_format != VLC_CODEC_FI32 )
68 p_mixer->mix = DoWork;
73 /*****************************************************************************
74 * DoWork: mix a new output buffer
75 *****************************************************************************/
76 static void DoWork( aout_mixer_t *p_mixer, aout_buffer_t * p_buffer )
79 aout_mixer_input_t * p_input = p_mixer->input[i];
80 int i_nb_channels = aout_FormatNbChannels( &p_mixer->fmt );
81 int i_buffer = p_buffer->i_nb_samples * sizeof(int32_t)
86 while ( p_input->is_invalid )
88 p_input = p_mixer->input[++i];
89 /* This can't crash because if no input has b_error == 0, the
90 * audio mixer cannot run and we can't be here. */
92 p_in = p_input->begin;
93 p_out = p_buffer->p_buffer;
97 ptrdiff_t i_available_bytes = (p_input->fifo.p_first->p_buffer
99 + p_input->fifo.p_first->i_nb_samples
103 if ( i_available_bytes < i_buffer )
105 aout_buffer_t * p_old_buffer;
107 vlc_memcpy( p_out, p_in, i_available_bytes );
108 i_buffer -= i_available_bytes;
109 p_out += i_available_bytes;
112 p_old_buffer = aout_FifoPop( NULL, &p_input->fifo );
113 aout_BufferFree( p_old_buffer );
114 if ( p_input->fifo.p_first == NULL )
116 msg_Err( p_mixer, "internal amix error" );
119 p_in = p_input->fifo.p_first->p_buffer;
123 vlc_memcpy( p_out, p_in, i_buffer );
124 p_input->begin = p_in + i_buffer;
129 /* Empty other FIFOs to avoid a memory leak. */
130 for ( i++; i < p_mixer->input_count; i++ )
132 aout_fifo_t * p_fifo;
133 aout_buffer_t * p_deleted;
135 p_input = p_mixer->input[i];
136 if ( p_input->is_invalid )
138 p_fifo = &p_input->fifo;
139 p_deleted = p_fifo->p_first;
140 while ( p_deleted != NULL )
142 aout_buffer_t * p_next = p_deleted->p_next;
143 aout_BufferFree( p_deleted );
146 p_fifo->p_first = NULL;
147 p_fifo->pp_last = &p_fifo->p_first;