chrome/utility/media_galleries/media_metadata_parser.h

   1 // Copyright 2013 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 CHROME_UTILITY_MEDIA_GALLERIES_MEDIA_METADATA_PARSER_H_
   6 #define CHROME_UTILITY_MEDIA_GALLERIES_MEDIA_METADATA_PARSER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "chrome/common/extensions/api/media_galleries.h"
  11
  12 namespace media {
  13 class DataSource;
  14 }
  15
  16 namespace metadata {
  17
  18 // This class takes a MIME type and data source and parses its metadata. It
  19 // handles audio, video, and images. It delegates its operations to FFMPEG,
  20 // libexif, etc. This class lives and operates on the utility thread of the
  21 // utility process, as we wish to sandbox potentially dangerous operations
  22 // on user-provided data.
  23 class MediaMetadataParser {
  24  public:
  25   typedef extensions::api::media_galleries::MediaMetadata MediaMetadata;
  26   typedef base::Callback<void(scoped_ptr<MediaMetadata>)> MetadataCallback;
  27
  28   // Does not take ownership of |source|. Caller is responsible for ensuring
  29   // that |source| outlives this object.
  30   MediaMetadataParser(media::DataSource* source, const std::string& mime_type);
  31
  32   ~MediaMetadataParser();
  33
  34   // |callback| is called on same message loop.
  35   void Start(const MetadataCallback& callback);
  36
  37  private:
  38   void PopulateAudioVideoMetadata();
  39
  40   media::DataSource* source_;
  41
  42   MetadataCallback callback_;
  43
  44   scoped_ptr<MediaMetadata> metadata_;
  45
  46   DISALLOW_COPY_AND_ASSIGN(MediaMetadataParser);
  47 };
  48
  49 }  // namespace metadata
  50
  51 #endif  // CHROME_UTILITY_MEDIA_GALLERIES_MEDIA_METADATA_PARSER_H_