1 files changed, 61 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/neteq/tools/audio_loop.cc b/third_party/libwebrtc/modules/audio_coding/neteq/tools/audio_loop.cc
new file mode 100644
index 0000000000..514e6eb2ee
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_coding/neteq/tools/audio_loop.cc
@@ -0,0 +1,61 @@
+/*
+ *  Copyright (c) 2013 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_coding/neteq/tools/audio_loop.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#include "absl/strings/string_view.h"
+
+namespace webrtc {
+namespace test {
+
+bool AudioLoop::Init(absl::string_view file_name,
+                     size_t max_loop_length_samples,
+                     size_t block_length_samples) {
+  FILE* fp = fopen(std::string(file_name).c_str(), "rb");
+  if (!fp)
+    return false;
+
+  audio_array_.reset(
+      new int16_t[max_loop_length_samples + block_length_samples]);
+  size_t samples_read =
+      fread(audio_array_.get(), sizeof(int16_t), max_loop_length_samples, fp);
+  fclose(fp);
+
+  // Block length must be shorter than the loop length.
+  if (block_length_samples > samples_read)
+    return false;
+
+  // Add an extra block length of samples to the end of the array, starting
+  // over again from the beginning of the array. This is done to simplify
+  // the reading process when reading over the end of the loop.
+  memcpy(&audio_array_[samples_read], audio_array_.get(),
+         block_length_samples * sizeof(int16_t));
+
+  loop_length_samples_ = samples_read;
+  block_length_samples_ = block_length_samples;
+  next_index_ = 0;
+  return true;
+}
+
+rtc::ArrayView<const int16_t> AudioLoop::GetNextBlock() {
+  // Check that the AudioLoop is initialized.
+  if (block_length_samples_ == 0)
+    return rtc::ArrayView<const int16_t>();
+
+  const int16_t* output_ptr = &audio_array_[next_index_];
+  next_index_ = (next_index_ + block_length_samples_) % loop_length_samples_;
+  return rtc::ArrayView<const int16_t>(output_ptr, block_length_samples_);
+}
+
+}  // namespace test
+}  // namespace webrtc