Module: OCR

Extended by:
OCR
Included in:
OCR
Defined in:
lib/ocr.rb

Overview

helper for OCR’ing single digits that were screen captured

Constant Summary collapse

GOCR = 
File.expand_path(File.dirname(__FILE__) + "/../vendor/gocr048.exe -C 0-9:/ ")
CACHE = 
{}
CACHE_FILE = 
File.expand_path('~/.sensible-cinema-ocr.marshal')

Instance Method Summary collapse

Instance Method Details

#clear_cache! ⇒ Object 



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# File 'lib/ocr.rb', line 59

def clear_cache!
  CACHE.clear
  File.delete CACHE_FILE if File.exist?(CACHE_FILE)
end

#identify_digit(memory_bitmap, options = {}) ⇒ Object

options are :might_be_colon, :should_invert



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# File 'lib/ocr.rb', line 12

def identify_digit memory_bitmap, options = {}
  require 'mini_magick' # installation woe, but actually pretty fast

  if CACHE.has_key?(memory_bitmap)
    return CACHE[memory_bitmap] unless (defined?($OCR_NO_CACHE) && $OCR_NO_CACHE)
  end
  if options[:might_be_colon]
    # do processing in-line <sigh>
    total = (memory_bitmap.scan(/\x00{5}+/)).length
    if total >= 3 # really should be 4 for VLC
      # it had some darkness...therefore have been a colon!
      CACHE[memory_bitmap] = ":"
      return ":"
    end
  end
  image = MiniMagick::Image.from_blob(memory_bitmap)
  # any operation on image is expensive, requires convert.exe in path...
  if options[:should_invert] 
    # hulu wants negate
    # but doesn't want sharpen, for whatever reason...
    # mogrify calls it negate...
    image.negate 
  else
    # youtube wants sharpen...
    image.sharpen(2)
  end

  image.format(:pnm)
  for level in [130, 100, 0] # 130 for vlc, 100 for hulu, 0 for some youtube
    a = `#{GOCR} -l #{level} #{image.path} 2>NUL`
    # a can be like "_1_\n"
    if a =~ /[0-9]/
      a.strip!
      a.gsub!('_', '')
      a = a.to_i
      CACHE[memory_bitmap] = a
      return a
    end
  end
  # don't cache it...could use up too much space on accident.
  nil
end

#serialize_cache_to_disk ⇒ Object 



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# File 'lib/ocr.rb', line 66

def serialize_cache_to_disk
  File.binwrite(CACHE_FILE, Marshal.dump(CACHE))
end

#unserialize_cache_from_disk ⇒ Object 



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# File 'lib/ocr.rb', line 70

def unserialize_cache_from_disk  
  if File.exist? CACHE_FILE
    CACHE.merge!(Marshal.load File.binread(CACHE_FILE))
  end
  
end

#version ⇒ Object 



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# File 'lib/ocr.rb', line 55

def version
  `#{GOCR} -h 2>&1`
end