1 files changed, 116 insertions, 0 deletions
diff --git a/src/common_audio/resampler/include/resampler.h b/src/common_audio/resampler/include/resampler.h
new file mode 100644
index 0000000000..38e6bd35b1
--- /dev/null
+++ b/src/common_audio/resampler/include/resampler.h
@@ -0,0 +1,116 @@
+/*
+ *  Copyright (c) 2011 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.
+ */
+
+
+/*
+ * A wrapper for resampling a numerous amount of sampling combinations.
+ */
+
+#ifndef WEBRTC_RESAMPLER_RESAMPLER_H_
+#define WEBRTC_RESAMPLER_RESAMPLER_H_
+
+#include "typedefs.h"
+
+namespace webrtc
+{
+
+// TODO(andrew): the implementation depends on the exact values of this enum.
+// It should be rewritten in a less fragile way.
+enum ResamplerType
+{
+    // 4 MSB = Number of channels
+    // 4 LSB = Synchronous or asynchronous
+
+    kResamplerSynchronous = 0x10,
+    kResamplerAsynchronous = 0x11,
+    kResamplerSynchronousStereo = 0x20,
+    kResamplerAsynchronousStereo = 0x21,
+    kResamplerInvalid = 0xff
+};
+
+// TODO(andrew): doesn't need to be part of the interface.
+enum ResamplerMode
+{
+    kResamplerMode1To1,
+    kResamplerMode1To2,
+    kResamplerMode1To3,
+    kResamplerMode1To4,
+    kResamplerMode1To6,
+    kResamplerMode1To12,
+    kResamplerMode2To3,
+    kResamplerMode2To11,
+    kResamplerMode4To11,
+    kResamplerMode8To11,
+    kResamplerMode11To16,
+    kResamplerMode11To32,
+    kResamplerMode2To1,
+    kResamplerMode3To1,
+    kResamplerMode4To1,
+    kResamplerMode6To1,
+    kResamplerMode12To1,
+    kResamplerMode3To2,
+    kResamplerMode11To2,
+    kResamplerMode11To4,
+    kResamplerMode11To8
+};
+
+class Resampler
+{
+
+public:
+    Resampler();
+    // TODO(andrew): use an init function instead.
+    Resampler(int inFreq, int outFreq, ResamplerType type);
+    ~Resampler();
+
+    // Reset all states
+    int Reset(int inFreq, int outFreq, ResamplerType type);
+
+    // Reset all states if any parameter has changed
+    int ResetIfNeeded(int inFreq, int outFreq, ResamplerType type);
+
+    // Synchronous resampling, all output samples are written to samplesOut
+    int Push(const WebRtc_Word16* samplesIn, int lengthIn, WebRtc_Word16* samplesOut,
+             int maxLen, int &outLen);
+
+    // Asynchronous resampling, input
+    int Insert(WebRtc_Word16* samplesIn, int lengthIn);
+
+    // Asynchronous resampling output, remaining samples are buffered
+    int Pull(WebRtc_Word16* samplesOut, int desiredLen, int &outLen);
+
+private:
+    // Generic pointers since we don't know what states we'll need
+    void* state1_;
+    void* state2_;
+    void* state3_;
+
+    // Storage if needed
+    WebRtc_Word16* in_buffer_;
+    WebRtc_Word16* out_buffer_;
+    int in_buffer_size_;
+    int out_buffer_size_;
+    int in_buffer_size_max_;
+    int out_buffer_size_max_;
+
+    // State
+    int my_in_frequency_khz_;
+    int my_out_frequency_khz_;
+    ResamplerMode my_mode_;
+    ResamplerType my_type_;
+
+    // Extra instance for stereo
+    Resampler* slave_left_;
+    Resampler* slave_right_;
+};
+
+} // namespace webrtc
+
+#endif // WEBRTC_RESAMPLER_RESAMPLER_H_