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
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Eugen Rochko 2019-10-03 01:09:12 +02:00 committed by GitHub
parent 0ce0baa9b5
commit ca22a22d7f
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4 changed files with 128 additions and 12 deletions

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@ -6,6 +6,7 @@ module Attachmentable
extend ActiveSupport::Concern
MAX_MATRIX_LIMIT = 16_777_216 # 4096x4096px or approx. 16MB
GIF_MATRIX_LIMIT = 921_600 # 1280x720px
included do
before_post_process :set_file_extensions
@ -42,8 +43,9 @@ module Attachmentable
next if attachment.blank? || !/image.*/.match?(attachment.content_type) || attachment.queued_for_write[:original].blank?
width, height = FastImage.size(attachment.queued_for_write[:original].path)
matrix_limit = attachment.content_type == 'image/gif' ? GIF_MATRIX_LIMIT : MAX_MATRIX_LIMIT
raise Mastodon::DimensionsValidationError, "#{width}x#{height} images are not supported, must be below #{MAX_MATRIX_LIMIT} sqpx" if width.present? && height.present? && (width * height >= MAX_MATRIX_LIMIT)
raise Mastodon::DimensionsValidationError, "#{width}x#{height} images are not supported" if width.present? && height.present? && (width * height > matrix_limit)
end
end

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@ -65,6 +65,17 @@ class MediaAttachment < ApplicationRecord
file_geometry_parser: FastGeometryParser,
blurhash: BLURHASH_OPTIONS,
},
original: {
keep_same_format: true,
convert_options: {
output: {
'map_metadata' => '-1',
'c:v' => 'copy',
'c:a' => 'copy',
},
},
},
}.freeze
AUDIO_STYLES = {
@ -90,10 +101,11 @@ class MediaAttachment < ApplicationRecord
'vf' => 'scale=\'trunc(iw/2)*2:trunc(ih/2)*2\'',
'vsync' => 'cfr',
'c:v' => 'h264',
'b:v' => '500K',
'maxrate' => '1300K',
'bufsize' => '1300K',
'frames:v' => 60 * 60 * 3,
'crf' => 18,
'map_metadata' => '-1',
},
},
}.freeze
@ -103,7 +115,7 @@ class MediaAttachment < ApplicationRecord
original: VIDEO_FORMAT,
}.freeze
IMAGE_LIMIT = 8.megabytes
IMAGE_LIMIT = 10.megabytes
VIDEO_LIMIT = 40.megabytes
belongs_to :account, inverse_of: :media_attachments, optional: true
@ -244,7 +256,9 @@ class MediaAttachment < ApplicationRecord
def set_meta
meta = populate_meta
return if meta == {}
file.instance_write :meta, meta
end
@ -287,6 +301,7 @@ class MediaAttachment < ApplicationRecord
def reset_parent_cache
return if status_id.nil?
Rails.cache.delete("statuses/#{status_id}")
end
end

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@ -1,5 +1,103 @@
# frozen_string_literal: true
class GifReader
attr_reader :animated
EXTENSION_LABELS = [0xf9, 0x01, 0xff].freeze
GIF_HEADERS = %w(GIF87a GIF89a).freeze
class GifReaderException; end
class UnknownImageType < GifReaderException; end
class CannotParseImage < GifReaderException; end
def self.animated?(path)
new(path).animated
rescue GifReaderException
false
end
def initialize(path, max_frames = 2)
@path = path
@nb_frames = 0
File.open(path, 'rb') do |s|
raise UnknownImageType unless GIF_HEADERS.include?(s.read(6))
# Skip to "packed byte"
s.seek(4, IO::SEEK_CUR)
# "Packed byte" gives us the size of the GIF color table
packed_byte, = s.read(1).unpack('C')
# Skip background color and aspect ratio
s.seek(2, IO::SEEK_CUR)
if packed_byte & 0x80 != 0
# GIF uses a global color table, skip it
s.seek(3 * (1 << ((packed_byte & 0x07) + 1)), IO::SEEK_CUR)
end
# Now read data
while @nb_frames < max_frames
separator = s.read(1)
case separator
when ',' # Image block
@nb_frames += 1
# Skip to "packed byte"
s.seek(8, IO::SEEK_CUR)
packed_byte, = s.read(1).unpack('C')
if packed_byte & 0x80 != 0
# Image uses a local color table, skip it
s.seek(3 * (1 << ((packed_byte & 0x07) + 1)), IO::SEEK_CUR)
end
# Skip lzw min code size
raise InvalidValue unless s.read(1).unpack('C')[0] >= 2
# Skip image data sub-blocks
skip_sub_blocks!(s)
when '!' # Extension block
skip_extension_block!(s)
when ';' # Trailer
break
else
raise CannotParseImage
end
end
end
@animated = @nb_frames > 1
end
private
def skip_extension_block!(file)
if EXTENSION_LABELS.include?(file.read(1).unpack('C')[0])
block_size, = file.read(1).unpack('C')
file.seek(block_size, IO::SEEK_CUR)
end
# Read until extension block end marker
skip_sub_blocks!(file)
end
# Skip sub-blocks up until block end marker
def skip_sub_blocks!(file)
loop do
size, = file.read(1).unpack('C')
break if size.zero?
file.seek(size, IO::SEEK_CUR)
end
end
end
module Paperclip
# This transcoder is only to be used for the MediaAttachment model
# to convert animated gifs to webm
@ -19,8 +117,7 @@ module Paperclip
private
def needs_convert?
num_frames = identify('-format %n :file', file: file.path).to_i
options[:style] == :original && num_frames > 1
options[:style] == :original && GifReader.animated?(file.path)
end
end
end

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@ -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