media/base/audio_video_metadata_extractor.h

   1 // Copyright 2014 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_AUDIO_VIDEO_METADATA_EXTRACTOR_H_
   6 #define MEDIA_BASE_AUDIO_VIDEO_METADATA_EXTRACTOR_H_
   7
   8 #include <map>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "media/base/media_export.h"
  14
  15 struct AVDictionary;
  16
  17 namespace media {
  18
  19 class DataSource;
  20
  21 // This class extracts a string dictionary of metadata tags for audio and video
  22 // files. It also provides the format name.
  23 class MEDIA_EXPORT AudioVideoMetadataExtractor {
  24  public:
  25   typedef std::map<std::string, std::string> TagDictionary;
  26
  27   struct StreamInfo {
  28     StreamInfo();
  29     ~StreamInfo();
  30     std::string type;
  31     TagDictionary tags;
  32   };
  33
  34   typedef std::vector<StreamInfo> StreamInfoVector;
  35
  36   AudioVideoMetadataExtractor();
  37   ~AudioVideoMetadataExtractor();
  38
  39   // Returns whether or not the fields were successfully extracted. Should only
  40   // be called once.
  41   bool Extract(DataSource* source, bool extract_attached_pics);
  42
  43   // Returns -1 if we cannot extract the duration. In seconds.
  44   double duration() const;
  45
  46   // Returns -1 for containers without video.
  47   int width() const;
  48   int height() const;
  49
  50   // Returns -1 if undefined.
  51   int rotation() const;
  52
  53   // Returns -1 or an empty string if the value is undefined.
  54   const std::string& album() const;
  55   const std::string& artist() const;
  56   const std::string& comment() const;
  57   const std::string& copyright() const;
  58   const std::string& date() const;
  59   int disc() const;
  60   const std::string& encoder() const;
  61   const std::string& encoded_by() const;
  62   const std::string& genre() const;
  63   const std::string& language() const;
  64   const std::string& title() const;
  65   int track() const;
  66
  67   // First element is the container. Subsequent elements are the child streams.
  68   const StreamInfoVector& stream_infos() const;
  69
  70   // Empty if Extract call did not request attached images, or if no attached
  71   // images were found.
  72   const std::vector<std::string>& attached_images_bytes() const;
  73
  74  private:
  75   void ExtractDictionary(AVDictionary* metadata, TagDictionary* raw_tags);
  76
  77   bool extracted_;
  78
  79   int duration_;
  80   int width_;
  81   int height_;
  82
  83   std::string album_;
  84   std::string artist_;
  85   std::string comment_;
  86   std::string copyright_;
  87   std::string date_;
  88   int disc_;
  89   std::string encoder_;
  90   std::string encoded_by_;
  91   std::string genre_;
  92   std::string language_;
  93   int rotation_;
  94   std::string title_;
  95   int track_;
  96
  97   StreamInfoVector stream_infos_;
  98
  99   std::vector<std::string> attached_images_bytes_;
 100
 101   DISALLOW_COPY_AND_ASSIGN(AudioVideoMetadataExtractor);
 102 };
 103
 104 }  // namespace media
 105
 106 #endif  // MEDIA_BASE_AUDIO_VIDEO_METADATA_EXTRACTOR_H_