Add support for writing raw encoder output to .ivf files.

webrtc/modules/video_coding/utility/ivf_file_writer.h

Index: webrtc/modules/video_coding/utility/ivf_file_writer.h
diff --git a/webrtc/modules/video_coding/utility/ivf_file_writer.h b/webrtc/modules/video_coding/utility/ivf_file_writer.h
new file mode 100644
index 0000000000000000000000000000000000000000..6e630f55f9e9b79f96045023f9d6cef38b2062fd
--- /dev/null
+++ b/webrtc/modules/video_coding/utility/ivf_file_writer.h
@@ -0,0 +1,52 @@
+/*
+ *  Copyright (c) 2016 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_VIDEO_CODING_UTILITY_IVF_FILE_WRITER_H_
+#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_IVF_FILE_WRITER_H_
+
+#include <memory>
+#include <string>
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/pathutils.h"
+#include "webrtc/base/stream.h"
+#include "webrtc/modules/include/module_common_types.h"
+#include "webrtc/video_frame.h"
+
+namespace webrtc {
+
+class IvfFileWriter {
+ public:
+  ~IvfFileWriter();
+
+  static std::unique_ptr<IvfFileWriter> Open(rtc::Pathname file_name,
+                                             RtpVideoCodecTypes codec_type);
+  static std::unique_ptr<IvfFileWriter> Open(rtc::StreamInterface* out_stream,
+                                             RtpVideoCodecTypes codec_type);
+  bool WriteFrame(const EncodedImage& encoded_image);
+  bool Close();
+
+ private:
+  IvfFileWriter(rtc::Pathname path_name, rtc::StreamInterface* out_stream);
+  bool WriteHeader(RtpVideoCodecTypes codec_type);
+
+  size_t num_frames_;
+  uint16_t width_;
+  uint16_t height_;
+  int64_t last_timestamp_;
+  rtc::Pathname file_name_;
+  std::unique_ptr<rtc::StreamInterface> out_stream_;
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(IvfFileWriter);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_VIDEO_CODING_UTILITY_IVF_FILE_WRITER_H_