Files
danbooru/app/logical/media_file/ugoira.rb

89 lines
2.7 KiB
Ruby

class MediaFile::Ugoira < MediaFile
class Error < StandardError; end
attr_reader :frame_data
def initialize(file, frame_data: {}, **options)
super(file, **options)
@frame_data = frame_data
end
def close
file.close
zipfile.close
preview_frame.close
end
def dimensions
preview_frame.dimensions
end
def preview(width, height)
preview_frame.preview(width, height)
end
def crop(width, height)
preview_frame.crop(width, height)
end
# XXX should take width and height and resize image
def convert
raise NotImplementedError, "can't convert ugoira to webm: ffmpeg or mkvmerge not installed" unless self.class.videos_enabled?
Dir.mktmpdir("ugoira-#{md5}") do |tmpdir|
output_file = Tempfile.new(["ugoira-conversion", ".webm"], binmode: true)
FileUtils.mkdir_p("#{tmpdir}/images")
zipfile.each do |entry|
path = File.join(tmpdir, "images", entry.name)
entry.extract(path)
end
# Duplicate last frame to avoid it being displayed only for a very short amount of time.
last_file_name = zipfile.entries.last.name
last_file_name =~ /\A(\d{6})(\.\w{,4})\Z/
new_last_index = $1.to_i + 1
file_ext = $2
new_last_filename = ("%06d" % new_last_index) + file_ext
path_from = File.join(tmpdir, "images", last_file_name)
path_to = File.join(tmpdir, "images", new_last_filename)
FileUtils.cp(path_from, path_to)
delay_sum = 0
timecodes_path = File.join(tmpdir, "timecodes.tc")
File.open(timecodes_path, "w+") do |f|
f.write("# timecode format v2\n")
frame_data.each do |img|
f.write("#{delay_sum}\n")
delay_sum += (img["delay"] || img["delay_msec"])
end
f.write("#{delay_sum}\n")
f.write("#{delay_sum}\n")
end
ext = zipfile.first.name.match(/\.(\w{,4})$/)[1]
ffmpeg_out, status = Open3.capture2e("ffmpeg -i #{tmpdir}/images/%06d.#{ext} -codec:v libvpx -crf 4 -b:v 5000k -an #{tmpdir}/tmp.webm")
raise Error, "ffmpeg failed: #{ffmpeg_out}" unless status.success?
mkvmerge_out, status = Open3.capture2e("mkvmerge -o #{output_file.path} --webm --timecodes 0:#{tmpdir}/timecodes.tc #{tmpdir}/tmp.webm")
raise Error, "mkvmerge failed: #{mkvmerge_out}" unless status.success?
MediaFile.open(output_file)
end
end
private
def zipfile
Zip::File.new(file.path)
end
def preview_frame
tempfile = Tempfile.new("ugoira-preview", binmode: true)
zipfile.entries.first.extract(tempfile.path) { true } # 'true' means overwrite the existing tempfile.
MediaFile.open(tempfile)
end
memoize :zipfile, :preview_frame, :dimensions
end