Data commit

Task/Bitmap-PPM-conversion-through-a-pipe/Ruby/bitmap-ppm-conversion-through-a-pipe.rb

@@ -0,0 +1,39 @@
+class Pixmap
+  PIXMAP_FORMATS = ["P3", "P6"]   # implemented output formats
+  PIXMAP_BINARY_FORMATS = ["P6"]  # implemented output formats which are binary
+
+  def write_ppm(ios, format="P6")
+    if not PIXMAP_FORMATS.include?(format)
+      raise NotImplementedError, "pixmap format #{format} has not been implemented"
+    end
+    ios.puts format, "#{@width} #{@height}", "255"
+    ios.binmode if PIXMAP_BINARY_FORMATS.include?(format)
+    @height.times do |y|
+      @width.times do |x|
+        case format
+        when "P3" then ios.print @data[x][y].values.join(" "),"\n"
+        when "P6" then ios.print @data[x][y].values.pack('C3')
+        end
+      end
+    end
+  end
+
+  def save(filename, opts={:format=>"P6"})
+    File.open(filename, 'w') do |f|
+      write_ppm(f, opts[:format])
+    end
+  end
+
+  def print(opts={:format=>"P6"})
+    write_ppm($stdout, opts[:format])
+  end
+
+  def save_as_jpeg(filename, quality=75)
+    pipe = IO.popen("convert ppm:- -quality #{quality} jpg:#{filename}", 'w')
+    write_ppm(pipe)
+    pipe.close
+  end
+end
+
+image = Pixmap.open('file.ppm')
+image.save_as_jpeg('file.jpg')