Rename neteq4 folder to neteq

Keep the old neteq4/audio_decoder_unittests.isolate while waiting for
a hard-coded reference to change.

This CL effectively reverts r6257 "Rename neteq4 folder to neteq".

BUG=2996
TBR=tina.legrand@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/21629004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6367 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/neteq/timestamp_scaler.h b/webrtc/modules/audio_coding/neteq/timestamp_scaler.h
new file mode 100644
index 0000000..59b8cc7
--- /dev/null
+++ b/webrtc/modules/audio_coding/neteq/timestamp_scaler.h
@@ -0,0 +1,68 @@
+/*
+ *  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_NETEQ_TIMESTAMP_SCALER_H_
+#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_TIMESTAMP_SCALER_H_
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/modules/audio_coding/neteq/packet.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+// Forward declaration.
+class DecoderDatabase;
+
+// This class scales timestamps for codecs that need timestamp scaling.
+// This is done for codecs where one RTP timestamp does not correspond to
+// one sample.
+class TimestampScaler {
+ public:
+  explicit TimestampScaler(const DecoderDatabase& decoder_database)
+      : first_packet_received_(false),
+        numerator_(1),
+        denominator_(1),
+        external_ref_(0),
+        internal_ref_(0),
+        decoder_database_(decoder_database) {}
+
+  virtual ~TimestampScaler() {}
+
+  // Start over.
+  virtual void Reset() { first_packet_received_ = false; }
+
+  // Scale the timestamp in |packet| from external to internal.
+  virtual void ToInternal(Packet* packet);
+
+  // Scale the timestamp for all packets in |packet_list| from external to
+  // internal.
+  virtual void ToInternal(PacketList* packet_list);
+
+  // Returns the internal equivalent of |external_timestamp|, given the
+  // RTP payload type |rtp_payload_type|.
+  virtual uint32_t ToInternal(uint32_t external_timestamp,
+                              uint8_t rtp_payload_type);
+
+  // Scales back to external timestamp. This is the inverse of ToInternal().
+  virtual uint32_t ToExternal(uint32_t internal_timestamp) const;
+
+ private:
+  bool first_packet_received_;
+  int numerator_;
+  int denominator_;
+  uint32_t external_ref_;
+  uint32_t internal_ref_;
+  const DecoderDatabase& decoder_database_;
+
+  DISALLOW_COPY_AND_ASSIGN(TimestampScaler);
+};
+
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_TIMESTAMP_SCALER_H_