1/***
2    Copyright 2012 Peter Meerwald <p.meerwald@bct-electronic.com>
3
4    PulseAudio is free software; you can redistribute it and/or modify
5    it under the terms of the GNU Lesser General Public License as published
6    by the Free Software Foundation; either version 2.1 of the License,
7    or (at your option) any later version.
8
9    PulseAudio is distributed in the hope that it will be useful, but
10    WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12    General Public License for more details.
13
14***/
15
16#ifdef HAVE_CONFIG_H
17#include <config.h>
18#endif
19
20#include <pulse/cdecl.h>
21
22PA_C_DECL_BEGIN
23#include <pulsecore/core-util.h>
24#include <pulsecore/modargs.h>
25#include "echo-cancel.h"
26PA_C_DECL_END
27
28bool pa_null_ec_init(pa_core *c, pa_echo_canceller *ec,
29                     pa_sample_spec *rec_ss, pa_channel_map *rec_map,
30                     pa_sample_spec *play_ss, pa_channel_map *play_map,
31                     pa_sample_spec *out_ss, pa_channel_map *out_map,
32                     uint32_t *nframes, const char *args) {
33    char strss_source[PA_SAMPLE_SPEC_SNPRINT_MAX];
34    char strss_sink[PA_SAMPLE_SPEC_SNPRINT_MAX];
35
36    *nframes = 256;
37    ec->params.null.out_ss = *out_ss;
38
39    *rec_ss = *out_ss;
40    *rec_map = *out_map;
41
42    pa_log_debug("null AEC: nframes=%u, sample spec source=%s, sample spec sink=%s", *nframes,
43                 pa_sample_spec_snprint(strss_source, sizeof(strss_source), out_ss),
44                 pa_sample_spec_snprint(strss_sink, sizeof(strss_sink), play_ss));
45
46    return true;
47}
48
49void pa_null_ec_run(pa_echo_canceller *ec, const uint8_t *rec, const uint8_t *play, uint8_t *out) {
50    /* The null implementation simply copies the recorded buffer to the output
51       buffer and ignores the play buffer. */
52    memcpy(out, rec, 256 * pa_frame_size(&ec->params.null.out_ss));
53}
54
55void pa_null_ec_done(pa_echo_canceller *ec) {
56}
57