Moves volume icon update in the timer
[vlc.git] / modules / audio_filter / resampler / trivial.c
1 /*****************************************************************************
2  * trivial.c : trivial resampler (skips samples or pads with zeroes)
3  *****************************************************************************
4  * Copyright (C) 2002, 2006 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
8  *
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.
13  * 
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.
18  *
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  *****************************************************************************/
23
24 /*****************************************************************************
25  * Preamble
26  *****************************************************************************/
27
28 #include <vlc/vlc.h>
29 #include <vlc_aout.h>
30
31 /*****************************************************************************
32  * Local prototypes
33  *****************************************************************************/
34 static int  Create    ( vlc_object_t * );
35
36 static void DoWork    ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
37                         aout_buffer_t * );
38
39 /*****************************************************************************
40  * Module descriptor
41  *****************************************************************************/
42 vlc_module_begin();
43     set_description( _("Audio filter for trivial resampling") );
44     set_capability( "audio filter", 1 );
45     set_category( CAT_AUDIO );
46     set_subcategory( SUBCAT_AUDIO_MISC );
47     set_callbacks( Create, NULL );
48 vlc_module_end();
49
50 /*****************************************************************************
51  * Create: allocate trivial resampler
52  *****************************************************************************/
53 static int Create( vlc_object_t *p_this )
54 {
55     aout_filter_t * p_filter = (aout_filter_t *)p_this;
56
57     if ( p_filter->input.i_rate == p_filter->output.i_rate
58           || p_filter->input.i_format != p_filter->output.i_format
59           || p_filter->input.i_physical_channels
60               != p_filter->output.i_physical_channels
61           || p_filter->input.i_original_channels
62               != p_filter->output.i_original_channels
63           || (p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
64                && p_filter->input.i_format != VLC_FOURCC('f','i','3','2')) )
65     {
66         return -1;
67     }
68
69     p_filter->pf_do_work = DoWork;
70     p_filter->b_in_place = VLC_TRUE;
71
72     return 0;
73 }
74
75 /*****************************************************************************
76  * DoWork: convert a buffer
77  *****************************************************************************/
78 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
79                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
80 {
81     int i_in_nb = p_in_buf->i_nb_samples;
82     int i_out_nb = i_in_nb * p_filter->output.i_rate
83                     / p_filter->input.i_rate;
84     int i_sample_bytes = aout_FormatNbChannels( &p_filter->input )
85                           * sizeof(int32_t);
86
87     /* Check if we really need to run the resampler */
88     if( p_aout->mixer.mixer.i_rate == p_filter->input.i_rate )
89     {
90         return;
91     }
92
93     if ( p_out_buf != p_in_buf )
94     {
95         /* For whatever reason the buffer allocator decided to allocate
96          * a new buffer. Currently, this never happens. */
97         p_aout->p_libvlc->pf_memcpy( p_out_buf->p_buffer, p_in_buf->p_buffer,
98                                   __MIN(i_out_nb, i_in_nb) * i_sample_bytes );
99     }
100
101     if ( i_out_nb > i_in_nb )
102     {
103         /* Pad with zeroes. */
104         memset( p_out_buf->p_buffer + i_in_nb * i_sample_bytes,
105                 0, (i_out_nb - i_in_nb) * i_sample_bytes );
106     }
107
108     p_out_buf->i_nb_samples = i_out_nb;
109     p_out_buf->i_nb_bytes = i_out_nb * i_sample_bytes;
110     p_out_buf->start_date = p_in_buf->start_date;
111     p_out_buf->end_date = p_out_buf->start_date + p_out_buf->i_nb_samples *
112         1000000 / p_filter->output.i_rate;
113 }