Merge audio_processing changes.

R=aluebs@webrtc.org, bjornv@webrtc.org
BUG=

Review URL: https://webrtc-codereview.appspot.com/32769004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7893 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_processing/transient/file_utils.h b/webrtc/modules/audio_processing/transient/file_utils.h
new file mode 100644
index 0000000..8dc477d
--- /dev/null
+++ b/webrtc/modules/audio_processing/transient/file_utils.h
@@ -0,0 +1,119 @@
+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_FILE_UTILS_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_FILE_UTILS_H_
+
+#include <string.h>
+
+#include "webrtc/base/compile_assert.h"
+#include "webrtc/system_wrappers/interface/file_wrapper.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+// This is a copy of the cast included in the Chromium codebase here:
+// http://cs.chromium.org/src/third_party/cld/base/casts.h
+template <class Dest, class Source>
+inline Dest bit_cast(const Source& source) {
+  // A compile error here means your Dest and Source have different sizes.
+  COMPILE_ASSERT(sizeof(Dest) == sizeof(Source),
+                 dest_and_source_have_different_sizes);
+
+  Dest dest;
+  memcpy(&dest, &source, sizeof(dest));
+  return dest;
+}
+
+// Converts the byte array with binary float representation to float.
+// Bytes must be in little-endian order.
+// Returns 0 if correct, -1 on error.
+int ConvertByteArrayToFloat(const uint8_t bytes[4], float* out);
+
+// Converts the byte array with binary double representation to double.
+// Bytes must be in little-endian order.
+// Returns 0 if correct, -1 on error.
+int ConvertByteArrayToDouble(const uint8_t bytes[8], double* out);
+
+// Converts a float to a byte array with binary float representation.
+// Bytes will be in little-endian order.
+// Returns 0 if correct, -1 on error.
+int ConvertFloatToByteArray(float value, uint8_t out_bytes[4]);
+
+// Converts a double to a byte array with binary double representation.
+// Bytes will be in little-endian order.
+// Returns 0 if correct, -1 on error.
+int ConvertDoubleToByteArray(double value, uint8_t out_bytes[8]);
+
+// Reads |length| 16-bit integers from |file| to |buffer|.
+// |file| must be previously opened.
+// Returns the number of 16-bit integers read or -1 on error.
+size_t ReadInt16BufferFromFile(FileWrapper* file,
+                               size_t length,
+                               int16_t* buffer);
+
+// Reads |length| 16-bit integers from |file| and stores those values
+// (converting them) in |buffer|.
+// |file| must be previously opened.
+// Returns the number of 16-bit integers read or -1 on error.
+size_t ReadInt16FromFileToFloatBuffer(FileWrapper* file,
+                                      size_t length,
+                                      float* buffer);
+
+// Reads |length| 16-bit integers from |file| and stores those values
+// (converting them) in |buffer|.
+// |file| must be previously opened.
+// Returns the number of 16-bit integers read or -1 on error.
+size_t ReadInt16FromFileToDoubleBuffer(FileWrapper* file,
+                                       size_t length,
+                                       double* buffer);
+
+// Reads |length| floats in binary representation (4 bytes) from |file| to
+// |buffer|.
+// |file| must be previously opened.
+// Returns the number of floats read or -1 on error.
+size_t ReadFloatBufferFromFile(FileWrapper* file, size_t length, float* buffer);
+
+// Reads |length| doubles in binary representation (8 bytes) from |file| to
+// |buffer|.
+// |file| must be previously opened.
+// Returns the number of doubles read or -1 on error.
+size_t ReadDoubleBufferFromFile(FileWrapper* file,
+                                size_t length,
+                                double* buffer);
+
+// Writes |length| 16-bit integers from |buffer| in binary representation (2
+// bytes) to |file|. It flushes |file|, so after this call there are no
+// writings pending.
+// |file| must be previously opened.
+// Returns the number of doubles written or -1 on error.
+size_t WriteInt16BufferToFile(FileWrapper* file,
+                              size_t length,
+                              const int16_t* buffer);
+
+// Writes |length| floats from |buffer| in binary representation (4 bytes) to
+// |file|. It flushes |file|, so after this call there are no writtings pending.
+// |file| must be previously opened.
+// Returns the number of doubles written or -1 on error.
+size_t WriteFloatBufferToFile(FileWrapper* file,
+                              size_t length,
+                              const float* buffer);
+
+// Writes |length| doubles from |buffer| in binary representation (8 bytes) to
+// |file|. It flushes |file|, so after this call there are no writings pending.
+// |file| must be previously opened.
+// Returns the number of doubles written or -1 on error.
+size_t WriteDoubleBufferToFile(FileWrapper* file,
+                               size_t length,
+                               const double* buffer);
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_TRANSIENT_FILE_UTILS_H_