Add bin and edit workflow

bin/gems/pdf-reader-2.14.1/examples/extract_fonts.rb

@@ -0,0 +1,82 @@
+#!/usr/bin/env ruby
+# coding: utf-8
+
+# This demonstrates a way to extract TTF fonts from a PDF. It could be expanded
+# to support extra font formats if required. Be aware that many PDFs subset
+# fonts before they're embedded so glyphs may be missing or re-arranged.
+
+require 'pdf/reader'
+
+module ExtractFonts
+
+  class Extractor
+
+    def page(page)
+      count = 0
+
+      return count if page.fonts.nil? || page.fonts.empty?
+
+      page.fonts.each do |label, font|
+        next if complete_refs[label]
+        complete_refs[label] = true
+
+        process_font(page, font)
+
+        count += 1
+      end
+
+      count
+    end
+
+    private
+
+    def process_font(page, font)
+      font = page.objects.deref(font)
+
+      case font[:Subtype]
+      when :Type0 then
+        font[:DescendantFonts].each { |f| process_font(page, f) }
+      when :TrueType, :CIDFontType2 then
+        ExtractFonts::TTF.new(page.objects, font).save("#{font[:BaseFont]}.ttf")
+      else
+        $stderr.puts "unsupported font type #{font[:Subtype]} for #{font[:BaseFont]}"
+      end
+    end
+
+    def complete_refs
+      @complete_refs ||= {}
+    end
+
+  end
+
+  class TTF
+
+    def initialize(objects, font)
+      @objects, @font = objects, font
+      @descriptor = @objects.deref(@font[:FontDescriptor])
+    end
+
+    def save(filename)
+      puts "#{filename}"
+      if @descriptor && @descriptor[:FontFile2]
+        stream = @objects.deref(@descriptor[:FontFile2])
+        File.open(filename, "wb") { |file| file.write stream.unfiltered_data }
+      else
+        $stderr.puts "- TTF font not embedded"
+      end
+    end
+  end
+end
+
+if ARGV.size == 0 # default file name
+  ARGV << File.expand_path(File.join(File.dirname(__dir__), "spec", "data", "cairo-unicode.pdf")) 
+end
+
+extractor = ExtractFonts::Extractor.new
+
+ARGV.each do |arg|
+  PDF::Reader.open(arg) do |reader|
+    page = reader.page(1)
+    extractor.page(page)
+  end
+end