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diff --git a/media/video/capture/screen/shared_buffer.h b/media/video/capture/screen/shared_buffer.h
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+++ b/media/video/capture/screen/shared_buffer.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_VIDEO_CAPTURE_SCREEN_SHARED_BUFFER_H_
+#define MEDIA_VIDEO_CAPTURE_SCREEN_SHARED_BUFFER_H_
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/process.h"
+#include "base/shared_memory.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+// Represents a memory buffer that can be shared between multiple processes.
+// It is more or less a convenience wrapper around base::SharedMemory providing
+// ref-counted lifetime management and unique buffer identifiers.
+class MEDIA_EXPORT SharedBuffer
+    : public base::RefCountedThreadSafe<SharedBuffer> {
+ public:
+  // Creates a new shared memory buffer of the given size and maps it to
+  // the memory of the calling process. If the operation fails for any reason,
+  // ptr() method will return NULL. This constructor set the identifier of this
+  // buffer to 0.
+  explicit SharedBuffer(uint32 size);
+
+  // Opens an existing shared memory buffer and maps it to the memory of
+  // the calling process (in read only mode). If the operation fails for any
+  // reason, ptr() method will return NULL.
+  SharedBuffer(int id, base::SharedMemoryHandle handle, uint32 size);
+
+  // Opens an existing shared memory buffer created by a different process and
+  // maps it to the memory of the calling process (in read only mode). If
+  // the operation fails for any reason, ptr() method will return NULL.
+  SharedBuffer(int id, base::SharedMemoryHandle handle,
+               base::ProcessHandle process, uint32 size);
+
+  // Returns pointer to the beginning of the allocated data buffer. Returns NULL
+  // if the object initialization failed for any reason.
+  void* ptr() const { return shared_memory_.memory(); }
+
+  // Returns handle of the shared memory section containing the allocated
+  // data buffer.
+  base::SharedMemoryHandle handle() const { return shared_memory_.handle(); }
+
+  // Calls SharedMemory::ShareToProcess to share the handle with a different
+  // process.
+  bool ShareToProcess(base::ProcessHandle process,
+                      base::SharedMemoryHandle* new_handle);
+
+  int id() const { return id_; }
+  uint32 size() const { return size_; }
+
+  void set_id(int id) { id_ = id; }
+
+ private:
+  friend class base::RefCountedThreadSafe<SharedBuffer>;
+  virtual ~SharedBuffer();
+
+  // Unique identifier of the buffer or 0 if ID hasn't been set.
+  int id_;
+
+  // Shared memory section backing up the buffer.
+  base::SharedMemory shared_memory_;
+
+  // Size of the buffer in bytes.
+  uint32 size_;
+
+  DISALLOW_COPY_AND_ASSIGN(SharedBuffer);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_VIDEO_CAPTURE_SCREEN_SHARED_BUFFER_H_