Class | Paperclip::Thumbnail |
In: |
lib/paperclip/thumbnail.rb
|
Parent: | Processor |
Handles thumbnailing images that are uploaded.
convert_options | [RW] | |
current_geometry | [RW] | |
format | [RW] | |
source_file_options | [RW] | |
target_geometry | [RW] | |
whiny | [RW] |
Creates a Thumbnail object set to work on the file given. It will attempt to transform the image into one defined by target_geometry which is a "WxH"-style string. format will be inferred from the file unless specified. Thumbnail creation will raise no errors unless whiny is true (which it is, by default. If convert_options is set, the options will be appended to the convert command upon image conversion
# File lib/paperclip/thumbnail.rb, line 13 13: def initialize file, options = {}, attachment = nil 14: super 15: 16: geometry = options[:geometry] 17: @file = file 18: @crop = geometry[-1,1] == '#' 19: @target_geometry = Geometry.parse geometry 20: @current_geometry = Geometry.from_file @file 21: @source_file_options = options[:source_file_options] 22: @convert_options = options[:convert_options] 23: @whiny = options[:whiny].nil? ? true : options[:whiny] 24: @format = options[:format] 25: 26: @source_file_options = @source_file_options.split(/\s+/) if @source_file_options.respond_to?(:split) 27: @convert_options = @convert_options.split(/\s+/) if @convert_options.respond_to?(:split) 28: 29: @current_format = File.extname(@file.path) 30: @basename = File.basename(@file.path, @current_format) 31: 32: end
Returns true if the target_geometry is meant to crop.
# File lib/paperclip/thumbnail.rb, line 35 35: def crop? 36: @crop 37: end
Performs the conversion of the file into a thumbnail. Returns the Tempfile that contains the new image.
# File lib/paperclip/thumbnail.rb, line 46 46: def make 47: src = @file 48: dst = Tempfile.new([@basename, @format ? ".#{@format}" : '']) 49: dst.binmode 50: 51: begin 52: parameters = [] 53: parameters << source_file_options 54: parameters << ":source" 55: parameters << transformation_command 56: parameters << convert_options 57: parameters << ":dest" 58: 59: parameters = parameters.flatten.compact.join(" ").strip.squeeze(" ") 60: 61: success = Paperclip.run("convert", parameters, :source => "#{File.expand_path(src.path)}[0]", :dest => File.expand_path(dst.path)) 62: rescue PaperclipCommandLineError => e 63: raise PaperclipError, "There was an error processing the thumbnail for #{@basename}" if @whiny 64: end 65: 66: dst 67: end
Returns the command ImageMagick‘s convert needs to transform the image into the thumbnail.
# File lib/paperclip/thumbnail.rb, line 71 71: def transformation_command 72: scale, crop = @current_geometry.transformation_to(@target_geometry, crop?) 73: trans = [] 74: trans << "-resize" << %["#{scale}"] unless scale.nil? || scale.empty? 75: trans << "-crop" << %["#{crop}"] << "+repage" if crop 76: trans 77: end