ACM: Adding unittests for the remixing functionality
On top of adding unittests for the remixing, the CL
moves the code tested to a separate file in order
to allow it to be tested.
Bug: webrtc:11007
Change-Id: I531736517bbcc715b3c1bf3a4256c42208c5b778
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/155740
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29839}
diff --git a/modules/audio_coding/acm2/acm_remixing.h b/modules/audio_coding/acm2/acm_remixing.h
new file mode 100644
index 0000000..661569b
--- /dev/null
+++ b/modules/audio_coding/acm2/acm_remixing.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2019 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.
+ */
+
+#ifndef MODULES_AUDIO_CODING_ACM2_ACM_REMIXING_H_
+#define MODULES_AUDIO_CODING_ACM2_ACM_REMIXING_H_
+
+#include <vector>
+
+#include "api/audio/audio_frame.h"
+
+namespace webrtc {
+
+// Stereo-to-mono downmixing. The length of the output must equal to the number
+// of samples per channel in the input.
+void DownMixFrame(const AudioFrame& input, rtc::ArrayView<int16_t> output);
+
+// Remixes the interleaved input frame to an interleaved output data vector. The
+// remixed data replaces the data in the output vector which is resized if
+// needed. The remixing supports any combination of input and output channels,
+// as well as any number of samples per channel.
+void ReMixFrame(const AudioFrame& input,
+ size_t num_output_channels,
+ std::vector<int16_t>* output);
+
+} // namespace webrtc
+
+#endif // MODULES_AUDIO_CODING_ACM2_ACM_REMIXING_H_