code.delx.au - pulseaudio/blob - src/modules/echo-cancel/speex.c

   1 /***
   2     This file is part of PulseAudio.
   3
   4     Copyright 2010 Wim Taymans <wim.taymans@gmail.com>
   5
   6     Contributor: Arun Raghavan <arun.raghavan@collabora.co.uk>
   7
   8     PulseAudio is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU Lesser General Public License as published
  10     by the Free Software Foundation; either version 2.1 of the License,
  11     or (at your option) any later version.
  12
  13     PulseAudio is distributed in the hope that it will be useful, but
  14     WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16     General Public License for more details.
  17
  18     You should have received a copy of the GNU Lesser General Public License
  19     along with PulseAudio; if not, write to the Free Software
  20     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21     USA.
  22 ***/
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include <pulsecore/modargs.h>
  29 #include "echo-cancel.h"
  30
  31 /* should be between 10-20 ms */
  32 #define DEFAULT_FRAME_SIZE_MS 20
  33 /* should be between 100-500 ms */
  34 #define DEFAULT_FILTER_SIZE_MS 200
  35
  36 static const char* const valid_modargs[] = {
  37     "frame_size_ms",
  38     "filter_size_ms",
  39     NULL
  40 };
  41
  42 static void pa_speex_ec_fixate_spec(pa_sample_spec *source_ss, pa_channel_map *source_map,
  43                                     pa_sample_spec *sink_ss, pa_channel_map *sink_map)
  44 {
  45     source_ss->format = PA_SAMPLE_S16NE;
  46
  47     *sink_ss = *source_ss;
  48     *sink_map = *source_map;
  49 }
  50
  51 pa_bool_t pa_speex_ec_init(pa_core *c, pa_echo_canceller *ec,
  52                            pa_sample_spec *source_ss, pa_channel_map *source_map,
  53                            pa_sample_spec *sink_ss, pa_channel_map *sink_map,
  54                            uint32_t *blocksize, const char *args)
  55 {
  56     int framelen, y, rate;
  57     uint32_t frame_size_ms, filter_size_ms;
  58     pa_modargs *ma;
  59
  60     if (!(ma = pa_modargs_new(args, valid_modargs))) {
  61         pa_log("Failed to parse submodule arguments.");
  62         goto fail;
  63     }
  64
  65     filter_size_ms = DEFAULT_FILTER_SIZE_MS;
  66     if (pa_modargs_get_value_u32(ma, "filter_size_ms", &filter_size_ms) < 0 || filter_size_ms < 1 || filter_size_ms > 2000) {
  67         pa_log("Invalid filter_size_ms specification");
  68         goto fail;
  69     }
  70
  71     frame_size_ms = DEFAULT_FRAME_SIZE_MS;
  72     if (pa_modargs_get_value_u32(ma, "frame_size_ms", &frame_size_ms) < 0 || frame_size_ms < 1 || frame_size_ms > 200) {
  73         pa_log("Invalid frame_size_ms specification");
  74         goto fail;
  75     }
  76
  77     pa_speex_ec_fixate_spec(source_ss, source_map, sink_ss, sink_map);
  78
  79     rate = source_ss->rate;
  80     framelen = (rate * frame_size_ms) / 1000;
  81     /* framelen should be a power of 2, round down to nearest power of two */
  82     y = 1 << ((8 * sizeof (int)) - 2);
  83     while (y > framelen)
  84       y >>= 1;
  85     framelen = y;
  86
  87     *blocksize = framelen * pa_frame_size (source_ss);
  88
  89     pa_log_debug ("Using framelen %d, blocksize %u, channels %d, rate %d", framelen, *blocksize, source_ss->channels, source_ss->rate);
  90
  91     ec->params.priv.speex.state = speex_echo_state_init_mc (framelen, (rate * filter_size_ms) / 1000, source_ss->channels, source_ss->channels);
  92
  93     if (!ec->params.priv.speex.state)
  94         goto fail;
  95
  96     speex_echo_ctl(ec->params.priv.speex.state, SPEEX_ECHO_SET_SAMPLING_RATE, &rate);
  97
  98     pa_modargs_free(ma);
  99     return TRUE;
 100
 101 fail:
 102     if (ma)
 103         pa_modargs_free(ma);
 104     return FALSE;
 105 }
 106
 107 void pa_speex_ec_run(pa_echo_canceller *ec, const uint8_t *rec, const uint8_t *play, uint8_t *out)
 108 {
 109     speex_echo_cancellation(ec->params.priv.speex.state, (const spx_int16_t *) rec, (const spx_int16_t *) play, (spx_int16_t *) out);
 110 }
 111
 112 void pa_speex_ec_done(pa_echo_canceller *ec)
 113 {
 114     speex_echo_state_destroy (ec->params.priv.speex.state);
 115     ec->params.priv.speex.state = NULL;
 116 }