media/base/video_frame_metadata.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_BASE_VIDEO_FRAME_METADATA_H_
   6 #define MEDIA_BASE_VIDEO_FRAME_METADATA_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "base/time/time.h"
  10 #include "base/values.h"
  11 #include "media/base/media_export.h"
  12
  13 namespace media {
  14
  15 class MEDIA_EXPORT VideoFrameMetadata {
  16  public:
  17   enum Key {
  18     // Video capture begin/end timestamps.  Consumers can use these values for
  19     // dynamic optimizations, logging stats, etc.  Use Get/SetTimeTicks() for
  20     // these keys.
  21     CAPTURE_BEGIN_TIME,
  22     CAPTURE_END_TIME,
  23
  24     // Represents either the fixed frame rate, or the maximum frame rate to
  25     // expect from a variable-rate source.  Use Get/SetDouble() for this key.
  26     FRAME_RATE,
  27
  28     NUM_KEYS
  29   };
  30
  31   VideoFrameMetadata();
  32   ~VideoFrameMetadata();
  33
  34   bool HasKey(Key key) const;
  35
  36   void Clear() { dictionary_.Clear(); }
  37
  38   // Setters.  Overwrites existing value, if present.
  39   void SetBoolean(Key key, bool value);
  40   void SetInteger(Key key, int value);
  41   void SetDouble(Key key, double value);
  42   void SetString(Key key, const std::string& value);
  43   void SetTimeTicks(Key key, const base::TimeTicks& value);
  44   void SetValue(Key key, scoped_ptr<base::Value> value);
  45
  46   // Getters.  Returns true if |key| was present and has the value has been set.
  47   bool GetBoolean(Key key, bool* value) const WARN_UNUSED_RESULT;
  48   bool GetInteger(Key key, int* value) const WARN_UNUSED_RESULT;
  49   bool GetDouble(Key key, double* value) const WARN_UNUSED_RESULT;
  50   bool GetString(Key key, std::string* value) const WARN_UNUSED_RESULT;
  51   bool GetTimeTicks(Key key, base::TimeTicks* value) const WARN_UNUSED_RESULT;
  52
  53   // Returns null if |key| was not present.
  54   const base::Value* GetValue(Key key) const WARN_UNUSED_RESULT;
  55
  56   // For serialization.
  57   void MergeInternalValuesInto(base::DictionaryValue* out) const;
  58   void MergeInternalValuesFrom(const base::DictionaryValue& in);
  59
  60  private:
  61   const base::BinaryValue* GetBinaryValue(Key key) const;
  62
  63   base::DictionaryValue dictionary_;
  64
  65   DISALLOW_COPY_AND_ASSIGN(VideoFrameMetadata);
  66 };
  67
  68 }  // namespace media
  69
  70 #endif  // MEDIA_BASE_VIDEO_FRAME_METADATA_H_