Class: Libis::Format::Converter::ImageConverter

Inherits:
Base
  • Object
show all
Defined in:
lib/libis/format/converter/image_converter.rb

Instance Attribute Summary

Attributes inherited from Base

#flags, #options

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Base

inherited, #using_temp

Constructor Details

#initialize ⇒ ImageConverter

Returns a new instance of ImageConverter.



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# File 'lib/libis/format/converter/image_converter.rb', line 27

def initialize
  @wm_image = nil
  super
end

Class Method Details

.input_types(format = nil) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 19

def self.input_types(format = nil)
  [:TIFF, :JPG, :PNG, :BMP, :GIF, :JP2, :PDF]
end

.output_types(_ = nil) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 23

def self.output_types(_ = nil)
  [:TIFF, :JPG, :PNG, :BMP, :GIF, :JP2, :PDF]
end

Instance Method Details

#assemble_and_convert(sources, target, format) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 157

def assemble_and_convert(sources, target, format)
  converted_pages = sources.inject([]) do |list, path|
    converted = Tempfile.new(['page-', ".#{Libis::Format::TypeDatabase.type_extentions(format).first}"])
    convert_image(path, converted.path, format)
    list << converted
  end
  MiniMagick::Tool::Convert.new do |b|
    converted_pages.each { |page| b << page.path }
    b << target
  end
  converted_pages.each do |temp_file|
    temp_file.close
    temp_file.unlink
  end
end

#colorspace(value) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 60

def colorspace(value)
  @options[:colorspace] = value
end

#convert(source, target, format, opts = {}) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 117

def convert(source, target, format, opts = {})
  super

  FileUtils.mkpath(File.dirname(target))

  if source.is_a? Array
    sources = source

    unless [:PDF, :TIFF, :GIF, :PBM, :PGM, :PPM].include? format
      error 'Can ony assemble multiple images into multi-page/layer format'
      return nil
    end

    assemble_and_convert(sources, target, format)

  elsif File.directory?(source)
    sources = Dir[File.join(source, '**', '*')].reject { |p| File.directory? p }

    unless [:TIFF, :PDF].include? format
      error 'Can ony assemble multiple images into multi-page/layer format'
      return nil
    end

    assemble_and_convert(sources, target, format)

  else

    image = MiniMagick::Image.new(source)

    if image.pages.size > 1
      assemble_and_convert(image.pages.map {|page| page.path}, target, format)
    else
      convert_image(source, target, format)
    end
  end

  target

end

#dpi(value) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 48

def dpi(value)
  @options[:density] = value
end

#flatten ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 56

def flatten
  @flags[:flatten] = true
end

#image_convert(_) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 32

def image_convert(_)
  #force usage of this converter
end

#quality(value) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 44

def quality(value)
  @options[:quality] = value
end

#resample(value) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 52

def resample(value)
  @options[:density] = value
end

#resize(geometry) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 40

def resize(geometry)
  @options[:resize] = geometry
end

#scale(percent) ⇒ Object 



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# File 'lib/libis/format/converter/image_converter.rb', line 36

def scale(percent)
  @options[:scale] = percent
end

#watermark(options = {}) ⇒ Object

Create or use a watermark image.

The watermark options are: - file: watermark image to use - text: text to create a watermark from - rotation: rotation of the watermark text (counter clockwise in degrees; integer number) - default 30 - size: size of the watermark (integer > 0, 1/n of image size) - default 4 - opacity: opacity of the watermark (fraction 0.0 - 1.0) - default 0.3 - gap: size of the gap between watermark instances. Fractions as percentage of widht/height. - default 0.2 If both options are given, the file will be used as-is if it exists and is a valid image file. Otherwise the file will be created or overwritten with a newly created watermark image.

The created watermark file will be a PNG image with transparent background containing the supplied text slanted by 30 degrees counter-clockwise.

Parameters:

  • options (Hash) (defaults to: {}) —

    Hash of options for watermark creation.



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# File 'lib/libis/format/converter/image_converter.rb', line 80

def watermark(options = {})
  text = options[:text] || '© LIBIS'
  image = options[:file] || (Dir::Tmpname.create(%w(wm_image .png)) { |_|})
  @wm_size = (options[:size] || '4').to_i
  @wm_opacity = ((options[:opacity] || 0.1).to_f * 100).to_i
  @wm_composition = options[:composition] || 'modulate'
  gap = ((options[:gap] || 0.2).to_f * 100).to_i
  rotation = 360 - (options[:rotation] || 30).to_i
  @wm_image = MiniMagick::Image.new(image)
  unless @wm_image.valid?
    # noinspection RubyResolve
    MiniMagick::Tool::Convert.new do |convert|
      # noinspection RubyLiteralArrayInspection
      convert.background 'transparent'
      convert.size('2000x2000')
      convert.gravity 'Center'
      convert.font('Helvetica').fill('black').pointsize(72) #.stroke('black').strokewidth(1)
      convert << "label:#{text}"
      convert.rotate rotation
      convert.trim.repage.+
      convert.bordercolor('transparent').border("#{gap}%")
      convert << image
    end
    if options[:file]
      @wm_image = MiniMagick::Image.new(image)
    else
      @wm_image = MiniMagick::Image.open(image)
      File.delete(image)
    end
    # noinspection RubyResolve
    unless @wm_image.valid?
      error "Problem creating watermark image '#{image}'."
      @wm_image = nil
    end
  end
end