1 /*****************************************************************************
2 * ugly.c : ugly resampler (changes pitch)
3 *****************************************************************************
4 * Copyright (C) 2002, 2006 the VideoLAN team
7 * Authors: Samuel Hocevar <sam@zoy.org>
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_plugin.h>
36 /*****************************************************************************
38 *****************************************************************************/
39 static int Create ( vlc_object_t * );
41 static void DoWork ( aout_instance_t *, aout_filter_t *, aout_buffer_t *,
44 /*****************************************************************************
46 *****************************************************************************/
48 set_description( _("Audio filter for ugly resampling") );
49 set_capability( "audio filter", 2 );
50 set_category( CAT_AUDIO );
51 set_subcategory( SUBCAT_AUDIO_MISC );
52 set_callbacks( Create, NULL );
55 /*****************************************************************************
56 * Create: allocate ugly resampler
57 *****************************************************************************/
58 static int Create( vlc_object_t *p_this )
60 aout_filter_t * p_filter = (aout_filter_t *)p_this;
62 if ( p_filter->input.i_rate == p_filter->output.i_rate
63 || p_filter->input.i_format != p_filter->output.i_format
64 || p_filter->input.i_physical_channels
65 != p_filter->output.i_physical_channels
66 || p_filter->input.i_original_channels
67 != p_filter->output.i_original_channels
68 || (p_filter->input.i_format != VLC_FOURCC('f','l','3','2')
69 && p_filter->input.i_format != VLC_FOURCC('f','i','3','2')) )
74 p_filter->pf_do_work = DoWork;
76 /* We don't want a new buffer to be created because we're not sure we'll
77 * actually need to resample anything. */
78 p_filter->b_in_place = true;
83 /*****************************************************************************
84 * DoWork: convert a buffer
85 *****************************************************************************/
86 static void DoWork( aout_instance_t * p_aout, aout_filter_t * p_filter,
87 aout_buffer_t * p_in_buf, aout_buffer_t * p_out_buf )
89 int32_t *p_in, *p_out = (int32_t*)p_out_buf->p_buffer;
94 unsigned int i_nb_channels = aout_FormatNbChannels( &p_filter->input );
95 unsigned int i_in_nb = p_in_buf->i_nb_samples;
96 unsigned int i_out_nb = i_in_nb * p_filter->output.i_rate
97 / p_filter->input.i_rate;
98 unsigned int i_sample_bytes = i_nb_channels * sizeof(int32_t);
99 unsigned int i_out, i_chan, i_remainder = 0;
101 /* Check if we really need to run the resampler */
102 if( p_aout->mixer.mixer.i_rate == p_filter->input.i_rate )
108 p_in = (int32_t *)alloca( p_in_buf->i_nb_bytes );
110 p_in_orig = p_in = (int32_t *)malloc( p_in_buf->i_nb_bytes );
117 vlc_memcpy( p_in, p_in_buf->p_buffer, p_in_buf->i_nb_bytes );
119 for( i_out = i_out_nb ; i_out-- ; )
121 for( i_chan = i_nb_channels ; i_chan ; )
124 p_out[i_chan] = p_in[i_chan];
126 p_out += i_nb_channels;
128 i_remainder += p_filter->input.i_rate;
129 while( i_remainder >= p_filter->output.i_rate )
131 p_in += i_nb_channels;
132 i_remainder -= p_filter->output.i_rate;
136 p_out_buf->i_nb_samples = i_out_nb;
137 p_out_buf->i_nb_bytes = i_out_nb * i_sample_bytes;
138 p_out_buf->start_date = p_in_buf->start_date;
139 p_out_buf->end_date = p_out_buf->start_date + p_out_buf->i_nb_samples *
140 1000000 / p_filter->output.i_rate;