RosettaCodeData/Task/Bitmap-PPM-conversion-throu.../Ruby/bitmap-ppm-conversion-throu...

40 lines
1.1 KiB
Ruby

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')