# File lib/pdf/reader/filter/depredict.rb, line 5 def initialize(options = {}) @options = options || {} end
Streams can be preprocessed to improve compression. This reverses the preprocessing
# File lib/pdf/reader/filter/depredict.rb, line 13 def filter(data) predictor = @options[:Predictor].to_i case predictor when 0, 1 then data when 2 then tiff_depredict(data) when 10, 11, 12, 13, 14, 15 then png_depredict(data) else raise MalformedPDFError, "Unrecognised predictor value (#{predictor})" end end