Add metadata value for presence of video channel in video blobs

Author: brenogazzola

activestorage/CHANGELOG.md

@@ -1,3 +1,10 @@
+*   Add metadata value for presence of video channel in video blobs
+
+    The `metadata` attribute of video blobs has a new boolean key named `video` that is set to
+    `true` if the file has an video channel and `false` if it doesn't.
+
+    *Breno Gazzola*
+
 *   Deprecate usage of `purge` and `purge_later` from the association extension.
 
     *Jacopo Beschi*

activestorage/lib/active_storage/analyzer/video_analyzer.rb

@@ -9,11 +9,12 @@ module ActiveStorage
   # * Angle (degrees)
   # * Display aspect ratio
   # * Audio (true if file has an audio channel, false if not)
+  # * Video (true if file has an video channel, false if not)
   #
   # Example:
   #
   #   ActiveStorage::Analyzer::VideoAnalyzer.new(blob).metadata
-  #   # => { width: 640.0, height: 480.0, duration: 5.0, angle: 0, display_aspect_ratio: [4, 3], audio: true }
+  #   # => { width: 640.0, height: 480.0, duration: 5.0, angle: 0, display_aspect_ratio: [4, 3], audio: true, video: true }
   #
   # When a video's angle is 90 or 270 degrees, its width and height are automatically swapped for convenience.
   #
@@ -24,7 +25,7 @@ def self.accept?(blob)
     end
 
     def metadata
-      { width: width, height: height, duration: duration, angle: angle, display_aspect_ratio: display_aspect_ratio, audio: audio? }.compact
+      { width: width, height: height, duration: duration, angle: angle, display_aspect_ratio: display_aspect_ratio, audio: audio?, video: video? }.compact
     end
 
     private
@@ -72,6 +73,10 @@ def audio?
         audio_stream.present?
       end
 
+      def video?
+        video_stream.present?
+      end
+
       def computed_height
         if encoded_width && display_height_scale
           encoded_width * display_height_scale

activestorage/test/analyzer/video_analyzer_test.rb

@@ -15,6 +15,7 @@ class ActiveStorage::Analyzer::VideoAnalyzerTest < ActiveSupport::TestCase
     assert_equal [4, 3], metadata[:display_aspect_ratio]
     assert_equal 5.166648, metadata[:duration]
     assert metadata[:audio]
+    assert metadata[:video]
     assert_not_includes metadata, :angle
   end
 
@@ -54,6 +55,7 @@ class ActiveStorage::Analyzer::VideoAnalyzerTest < ActiveSupport::TestCase
     assert_equal 480, metadata[:height]
     assert_equal 5.229000, metadata[:duration]
     assert metadata[:audio]
+    assert metadata[:video]
   end
 
   test "analyzing a video without a video stream" do
@@ -63,12 +65,15 @@ class ActiveStorage::Analyzer::VideoAnalyzerTest < ActiveSupport::TestCase
     assert_not_includes metadata, :width
     assert_not_includes metadata, :height
     assert_equal 1.022000, metadata[:duration]
+    assert_not metadata[:video]
+    assert metadata[:audio]
   end
 
   test "analyzing a video without an audio stream" do
     blob = create_file_blob(filename: "video_without_audio_stream.mp4", content_type: "video/mp4")
     metadata = extract_metadata_from(blob)
 
+    assert metadata[:video]
     assert_not metadata[:audio]
   end
 end

guides/source/configuring.md

@@ -987,7 +987,7 @@ You can find more detailed configuration options in the
 
 * `config.active_storage.variant_processor` accepts a symbol `:mini_magick` or `:vips`, specifying whether variant transformations will be performed with MiniMagick or ruby-vips. The default is `:mini_magick`.
 
-* `config.active_storage.analyzers` accepts an array of classes indicating the analyzers available for Active Storage blobs. The default is `[ActiveStorage::Analyzer::ImageAnalyzer, ActiveStorage::Analyzer::VideoAnalyzer, ActiveStorage::Analyzer::AudioAnalyzer]`. The image analyzer can extract width and height of an image blob; the video analyzer can extract width, height, duration, angle, aspect ratio and presence/absence of audio channel of a video blob; the audio analyzer can extract duration and bit rate of an audio blob.
+* `config.active_storage.analyzers` accepts an array of classes indicating the analyzers available for Active Storage blobs. The default is `[ActiveStorage::Analyzer::ImageAnalyzer, ActiveStorage::Analyzer::VideoAnalyzer, ActiveStorage::Analyzer::AudioAnalyzer]`. The image analyzer can extract width and height of an image blob; the video analyzer can extract width, height, duration, angle, aspect ratio and presence/absence of video/audio channels of a video blob; the audio analyzer can extract duration and bit rate of an audio blob.
 
 * `config.active_storage.previewers` accepts an array of classes indicating the image previewers available in Active Storage blobs. The default is `[ActiveStorage::Previewer::PopplerPDFPreviewer, ActiveStorage::Previewer::MuPDFPreviewer, ActiveStorage::Previewer::VideoPreviewer]`. `PopplerPDFPreviewer` and `MuPDFPreviewer` can generate a thumbnail from the first page of a PDF blob; `VideoPreviewer` from the relevant frame of a video blob.