Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/third_party/libwebrtc/modules/audio_processing/agc2/biquad_filter.cc b/third_party/libwebrtc/modules/audio_processing/agc2/biquad_filter.cc
new file mode 100644
index 0000000000..c1b80d7320
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_processing/agc2/biquad_filter.cc
@@ -0,0 +1,60 @@
+/*
+ *  Copyright (c) 2016 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/agc2/biquad_filter.h"
+
+#include "rtc_base/arraysize.h"
+
+namespace webrtc {
+
+BiQuadFilter::BiQuadFilter(const Config& config)
+    : config_(config), state_({}) {}
+
+BiQuadFilter::~BiQuadFilter() = default;
+
+void BiQuadFilter::SetConfig(const Config& config) {
+  config_ = config;
+  state_ = {};
+}
+
+void BiQuadFilter::Reset() {
+  state_ = {};
+}
+
+void BiQuadFilter::Process(rtc::ArrayView<const float> x,
+                           rtc::ArrayView<float> y) {
+  RTC_DCHECK_EQ(x.size(), y.size());
+  const float config_a0 = config_.a[0];
+  const float config_a1 = config_.a[1];
+  const float config_b0 = config_.b[0];
+  const float config_b1 = config_.b[1];
+  const float config_b2 = config_.b[2];
+  float state_a0 = state_.a[0];
+  float state_a1 = state_.a[1];
+  float state_b0 = state_.b[0];
+  float state_b1 = state_.b[1];
+  for (size_t k = 0, x_size = x.size(); k < x_size; ++k) {
+    // Use a temporary variable for `x[k]` to allow in-place processing.
+    const float tmp = x[k];
+    float y_k = config_b0 * tmp + config_b1 * state_b0 + config_b2 * state_b1 -
+                config_a0 * state_a0 - config_a1 * state_a1;
+    state_b1 = state_b0;
+    state_b0 = tmp;
+    state_a1 = state_a0;
+    state_a0 = y_k;
+    y[k] = y_k;
+  }
+  state_.a[0] = state_a0;
+  state_.a[1] = state_a1;
+  state_.b[0] = state_b0;
+  state_.b[1] = state_b1;
+}
+
+}  // namespace webrtc