Fix performance of GIF re-encoding (#12057)

* Change animated GIF detection to not shell out to ImageMagick

Signed-off-by: Eugen Rochko <eugen@zeonfederated.com>

* Change video encoding parameters to limit to 10800 video frames

Signed-off-by: Eugen Rochko <eugen@zeonfederated.com>

* Limit GIF image size further

Signed-off-by: Eugen Rochko <eugen@zeonfederated.com>

* Always strip metadata from video files

* Fix code style issues

lib/paperclip/video_transcoder.rb

@@ -6,7 +6,9 @@ module Paperclip
   class VideoTranscoder < Paperclip::Processor
     def make
       meta = ::Av.cli.identify(@file.path)
+
       attachment.instance.type = MediaAttachment.types[:gifv] unless meta[:audio_encode]
+      options[:format] = File.extname(attachment.instance.file_file_name)[1..-1] if options[:keep_same_format]
 
       Paperclip::Transcoder.make(file, options, attachment)
     end