Class Paperclip::Thumbnail
In: lib/paperclip/thumbnail.rb
Parent: Processor

Handles thumbnailing images that are uploaded.

Methods

convert_options?   crop?   make   new   transformation_command  

Attributes

convert_options  [RW] 
current_geometry  [RW] 
format  [RW] 
target_geometry  [RW] 
whiny  [RW] 

Public Class methods

new(file, options = {})

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

[Source]

    # File lib/paperclip/thumbnail.rb, line 13
13:     def initialize file, options = {}, attachment = nil
14:       super
15:       geometry          = options[:geometry]
16:       @file             = file
17:       @crop             = geometry[-1,1] == '#'
18:       @target_geometry  = Geometry.parse geometry
19:       @current_geometry = Geometry.from_file @file
20:       @convert_options  = options[:convert_options]
21:       @whiny            = options[:whiny].nil? ? true : options[:whiny]
22:       @format           = options[:format]
23: 
24:       @current_format   = File.extname(@file.path)
25:       @basename         = File.basename(@file.path, @current_format)
26:     end

Public Instance methods

convert_options?()

Returns true if the image is meant to make use of additional convert options.

[Source]

    # File lib/paperclip/thumbnail.rb, line 34
34:     def convert_options?
35:       not @convert_options.blank?
36:     end
crop?()

Returns true if the target_geometry is meant to crop.

[Source]

    # File lib/paperclip/thumbnail.rb, line 29
29:     def crop?
30:       @crop
31:     end
make()

Performs the conversion of the file into a thumbnail. Returns the Tempfile that contains the new image.

[Source]

    # File lib/paperclip/thumbnail.rb, line 40
40:     def make
41:       src = @file
42:       dst = Tempfile.new([@basename, @format].compact.join("."))
43:       dst.binmode
44: 
45:       command = "\"\#{ File.expand_path(src.path) }[0]\"\n\#{ transformation_command }\n\"\#{ File.expand_path(dst.path) }\"\n"
46: 
47:       begin
48:         success = Paperclip.run("convert", command.gsub(/\s+/, " "))
49:       rescue PaperclipCommandLineError
50:         raise PaperclipError, "There was an error processing the thumbnail for #{@basename}" if @whiny
51:       end
52: 
53:       dst
54:     end
transformation_command()

Returns the command ImageMagick‘s convert needs to transform the image into the thumbnail.

[Source]

    # File lib/paperclip/thumbnail.rb, line 63
63:     def transformation_command
64:       scale, crop = @current_geometry.transformation_to(@target_geometry, crop?)
65:       trans = "-resize \"#{scale}\""
66:       trans << " -crop \"#{crop}\" +repage" if crop
67:       trans << " #{convert_options}" if convert_options?
68:       trans
69:     end

[Validate]