blob: 62b3ae084056e7faa4ceaf4bd477f2062f225936 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
/*
* Copyright (c) 2022 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "modules/audio_processing/aec3/multi_channel_content_detector.h"
#include <cmath>
namespace webrtc {
namespace {
// Compares the left and right channels in the render `frame` to determine
// whether the signal is a proper stereo signal. To allow for differences
// introduced by hardware drivers, a threshold `detection_threshold` is used for
// the detection.
bool IsProperStereo(const std::vector<std::vector<std::vector<float>>>& frame,
float detection_threshold) {
if (frame[0].size() < 2) {
return false;
}
for (size_t band = 0; band < frame.size(); ++band) {
for (size_t k = 0; k < frame[band][0].size(); ++k) {
if (std::fabs(frame[band][0][k] - frame[band][1][k]) >
detection_threshold) {
return true;
}
}
}
return false;
}
} // namespace
MultiChannelContentDetector::MultiChannelContentDetector(
bool detect_stereo_content,
int num_render_input_channels,
float detection_threshold)
: detect_stereo_content_(detect_stereo_content),
detection_threshold_(detection_threshold),
proper_multichannel_content_detected_(!detect_stereo_content &&
num_render_input_channels > 1) {}
bool MultiChannelContentDetector::UpdateDetection(
const std::vector<std::vector<std::vector<float>>>& frame) {
bool previous_proper_multichannel_content_detected_ =
proper_multichannel_content_detected_;
if (detect_stereo_content_ && !proper_multichannel_content_detected_) {
proper_multichannel_content_detected_ =
IsProperStereo(frame, detection_threshold_);
}
return previous_proper_multichannel_content_detected_ !=
proper_multichannel_content_detected_;
}
} // namespace webrtc
|
