lib/grim/image_magick_processor.rb in grim-1.1.0 vs lib/grim/image_magick_processor.rb in grim-1.2.0

@@ -1,35 +1,47 @@
 module Grim
   class ImageMagickProcessor
 
     # ghostscript prints out a warning, this regex matches it
     WarningRegex = /\*\*\*\*.*\n/
+    DefaultImagemagickPath = 'convert'
+    DefaultGhostScriptPath = 'gs'
 
     def initialize(options={})
-      @imagemagick_path = options[:imagemagick_path] || 'convert'
-      @ghostscript_path = options[:ghostscript_path]
-      @original_path        = ENV['PATH']
+      @imagemagick_path = options[:imagemagick_path] || DefaultImagemagickPath
+      @ghostscript_path = options[:ghostscript_path] || DefaultGhostScriptPath
+      @original_path    = ENV['PATH']
     end
 
     def count(path)
-      command = ["-dNODISPLAY", "-q",
+      command = [@ghostscript_path, "-dNODISPLAY", "-q",
         "-sFile=#{Shellwords.shellescape(path)}",
         File.expand_path('../../../lib/pdf_info.ps', __FILE__)]
-      @ghostscript_path ? command.unshift(@ghostscript_path) : command.unshift('gs')
       result = `#{command.join(' ')}`
       result.gsub(WarningRegex, '').to_i
     end
 
     def save(pdf, index, path, options)
-      width   = options.fetch(:width,   Grim::WIDTH)
-      density = options.fetch(:density, Grim::DENSITY)
-      quality = options.fetch(:quality, Grim::QUALITY)
+      width      = options.fetch(:width,   Grim::WIDTH)
+      density    = options.fetch(:density, Grim::DENSITY)
+      quality    = options.fetch(:quality, Grim::QUALITY)
       colorspace = options.fetch(:colorspace, Grim::COLORSPACE)
-      command = [@imagemagick_path, "-resize", width.to_s, "-antialias", "-render",
-        "-quality", quality.to_s, "-colorspace", colorspace,
-        "-interlace", "none", "-density", density.to_s,
-        "#{Shellwords.shellescape(pdf.path)}[#{index}]", path]
-      command.unshift("PATH=#{File.dirname(@ghostscript_path)}:#{ENV['PATH']}") if @ghostscript_path
+      alpha      = options[:alpha]
+
+      command = []
+      command << @imagemagick_path
+      command << "-resize #{width}"
+      command << "-alpha #{alpha}" if alpha
+      command << "-antialias"
+      command << "-render"
+      command << "-quality #{quality}"
+      command << "-colorspace #{colorspace}"
+      command << "-interlace none"
+      command << "-density #{density}"
+      command << "#{Shellwords.shellescape(pdf.path)}[#{index}]"
+      command << path
+
+      command.unshift("PATH=#{File.dirname(@ghostscript_path)}:#{ENV['PATH']}") if @ghostscript_path && @ghostscript_path != DefaultGhostScriptPath
 
       result = `#{command.join(' ')}`
 
       $? == 0 || raise(UnprocessablePage, result)
     end