* all: added a new access_filter module: record + one hotkey to start/stop
[vlc.git] / modules / audio_filter / resampler / ugly.c
1 /*****************************************************************************
2  * ugly.c : ugly resampler (changes pitch)
3  *****************************************************************************
4  * Copyright (C) 2002 VideoLAN
5  * $Id$
6  *
7  * Authors: Samuel Hocevar <sam@zoy.org>
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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
22  *****************************************************************************/
23
24 /*****************************************************************************
25  * Preamble
26  *****************************************************************************/
27 #include <stdlib.h>                                      /* malloc(), free() */
28 #include <string.h>
29
30 #include <vlc/vlc.h>
31 #include "audio_output.h"
32 #include "aout_internal.h"
33
34 /*****************************************************************************
35  * Local prototypes
36  *****************************************************************************/
37 static int  Create    ( vlc_object_t * );
38
39 static void DoWork    ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
40                         aout_buffer_t * );
41
42 /*****************************************************************************
43  * Module descriptor
44  *****************************************************************************/
45 vlc_module_begin();
46     set_description( _("audio filter for ugly resampling") );
47     set_capability( "audio filter", 2 );
48     set_category( CAT_AUDIO );
49     set_subcategory( SUBCAT_AUDIO_MISC );
50     set_callbacks( Create, NULL );
51 vlc_module_end();
52
53 /*****************************************************************************
54  * Create: allocate ugly resampler
55  *****************************************************************************/
56 static int Create( vlc_object_t *p_this )
57 {
58     aout_filter_t * p_filter = (aout_filter_t *)p_this;
59
60     if ( p_filter->input.i_rate == p_filter->output.i_rate
61           || p_filter->input.i_format != p_filter->output.i_format
62           || p_filter->input.i_physical_channels
63               != p_filter->output.i_physical_channels
64           || p_filter->input.i_original_channels
65               != p_filter->output.i_original_channels
66           || (p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
67                && p_filter->input.i_format != VLC_FOURCC('f','i','3','2')) )
68     {
69         return VLC_EGENERIC;
70     }
71
72     p_filter->pf_do_work = DoWork;
73
74     /* We don't want a new buffer to be created because we're not sure we'll
75      * actually need to resample anything. */
76     p_filter->b_in_place = VLC_TRUE;
77
78     return VLC_SUCCESS;
79 }
80
81 /*****************************************************************************
82  * DoWork: convert a buffer
83  *****************************************************************************/
84 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
85                     aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
86 {
87     int32_t *p_in, *p_out = (int32_t*)p_out_buf->p_buffer;
88
89     unsigned int i_nb_channels = aout_FormatNbChannels( &p_filter->input );
90     unsigned int i_in_nb = p_in_buf->i_nb_samples;
91     unsigned int i_out_nb = i_in_nb * p_filter->output.i_rate
92                                     / p_filter->input.i_rate;
93     unsigned int i_sample_bytes = i_nb_channels * sizeof(int32_t);
94     unsigned int i_out, i_chan, i_remainder = 0;
95
96     /* Check if we really need to run the resampler */
97     if( p_aout->mixer.mixer.i_rate == p_filter->input.i_rate )
98     {
99         return;
100     }
101
102 #ifdef HAVE_ALLOCA
103     p_in = (int32_t *)alloca( p_in_buf->i_nb_bytes );
104 #else
105     p_in_orig = p_in = (int32_t *)malloc( p_in_buf->i_nb_bytes );
106 #endif
107     if( p_in == NULL )
108     {
109         return;
110     }
111
112     p_aout->p_vlc->pf_memcpy( p_in, p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
113
114     for( i_out = i_out_nb ; i_out-- ; )
115     {
116         for( i_chan = i_nb_channels ; i_chan ; )
117         {
118             i_chan--;
119             p_out[i_chan] = p_in[i_chan];
120         }
121         p_out += i_nb_channels;
122
123         i_remainder += p_filter->input.i_rate;
124         while( i_remainder >= p_filter->output.i_rate )
125         {
126             p_in += i_nb_channels;
127             i_remainder -= p_filter->output.i_rate;
128         }
129     }
130
131     p_out_buf->i_nb_samples = i_out_nb;
132     p_out_buf->i_nb_bytes = i_out_nb * i_sample_bytes;
133     p_out_buf->start_date = p_in_buf->start_date;
134     p_out_buf->end_date = p_out_buf->start_date + p_out_buf->i_nb_samples *
135         1000000 / p_filter->output.i_rate;
136
137 #ifndef HAVE_ALLOCA
138     free( p_in_orig );
139 #endif
140
141 }