ACM2 integration with NetEq 4.

nack{.cc, .h, _unittest.cc} are basically copies from main/source/ folder, with cpplint warning cleaned up.

BUG=
R=andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2190009

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4736 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/audio_coding/main/acm2/acm_opus.h

@@ -0,0 +1,50 @@
+/*
+ *  Copyright (c) 2012 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 WEBRTC_MODULES_AUDIO_CODING_MAIN_SOURCE_ACM_OPUS_H_
+#define WEBRTC_MODULES_AUDIO_CODING_MAIN_SOURCE_ACM_OPUS_H_
+
+#include "webrtc/common_audio/resampler/include/resampler.h"
+#include "webrtc/modules/audio_coding/main/source/acm_generic_codec.h"
+
+struct WebRtcOpusEncInst;
+struct WebRtcOpusDecInst;
+
+namespace webrtc {
+
+class ACMOpus : public ACMGenericCodec {
+ public:
+  explicit ACMOpus(int16_t codec_id);
+  ~ACMOpus();
+
+  ACMGenericCodec* CreateInstance(void);
+
+  int16_t InternalEncode(uint8_t* bitstream, int16_t* bitstream_len_byte);
+
+  int16_t InternalInitEncoder(WebRtcACMCodecParams *codec_params);
+
+ protected:
+  void DestructEncoderSafe();
+
+  int16_t InternalCreateEncoder();
+
+  void InternalDestructEncoderInst(void* ptr_inst);
+
+  int16_t SetBitRateSafe(const int32_t rate);
+
+  WebRtcOpusEncInst* encoder_inst_ptr_;
+  uint16_t sample_freq_;
+  uint16_t bitrate_;
+  int channels_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_CODING_MAIN_SOURCE_ACM_OPUS_H_