diff options
Diffstat (limited to 'activestorage/lib/active_storage/analyzer/video_analyzer.rb')
-rw-r--r-- | activestorage/lib/active_storage/analyzer/video_analyzer.rb | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/activestorage/lib/active_storage/analyzer/video_analyzer.rb b/activestorage/lib/active_storage/analyzer/video_analyzer.rb new file mode 100644 index 0000000000..408b5e58e9 --- /dev/null +++ b/activestorage/lib/active_storage/analyzer/video_analyzer.rb @@ -0,0 +1,79 @@ +# frozen_string_literal: true + +require "active_support/core_ext/hash/compact" + +module ActiveStorage + # Extracts the following from a video blob: + # + # * Width (pixels) + # * Height (pixels) + # * Duration (seconds) + # * Angle (degrees) + # * Aspect ratio + # + # Example: + # + # ActiveStorage::VideoAnalyzer.new(blob).metadata + # # => { width: 640, height: 480, duration: 5.0, angle: 0, aspect_ratio: [4, 3] } + # + # This analyzer requires the {ffmpeg}[https://www.ffmpeg.org] system library, which is not provided by Rails. You must + # install ffmpeg yourself to use this analyzer. + class Analyzer::VideoAnalyzer < Analyzer + def self.accept?(blob) + blob.video? + end + + def metadata + { width: width, height: height, duration: duration, angle: angle, aspect_ratio: aspect_ratio }.compact + end + + private + def width + Integer(video_stream["width"]) if video_stream["width"] + end + + def height + Integer(video_stream["height"]) if video_stream["height"] + end + + def duration + Float(video_stream["duration"]) if video_stream["duration"] + end + + def angle + Integer(tags["rotate"]) if tags["rotate"] + end + + def aspect_ratio + if descriptor = video_stream["display_aspect_ratio"] + descriptor.split(":", 2).collect(&:to_i) + end + end + + + def tags + @tags ||= video_stream["tags"] || {} + end + + def video_stream + @video_stream ||= streams.detect { |stream| stream["codec_type"] == "video" } || {} + end + + def streams + probe["streams"] || [] + end + + def probe + download_blob_to_tempfile { |file| probe_from(file) } + end + + def probe_from(file) + IO.popen([ "ffprobe", "-print_format", "json", "-show_streams", "-v", "error", file.path ]) do |output| + JSON.parse(output.read) + end + rescue Errno::ENOENT + logger.info "Skipping video analysis because ffmpeg isn't installed" + {} + end + end +end |