Making the random seeded pixel values a bit protected from infinite loopes.

encode_image.rb

@@ -7,11 +7,11 @@ class EncodeImage
   @@utils = nil
 
 
-  def initialize(p, m, i)
+  def initialize(p, m, uri)
     @@password = p
     @@message  = m
 
-    @@utils = ImageUtils.new(@@password, @@message, i)
+    @@utils = ImageUtils.new(@@password, @@message, uri)
 
     @@table = @@utils.generateLookupTable
   end
@@ -30,59 +30,6 @@ class EncodeImage
       msg_bits = pixel.encodeBits(msg_bits)
     end
 
-#    for x in 0..s[:width]-1
-#      for y in 0..s[:height]-1
-
-#        loc = {"x": x, "y": y}
-#        if @@table.include? loc then
-#          pixel = @@utils.getImage.getPixel(x, y)
-#          msg_bits = pixel.encodeBits(msg_bits)
-#        end
-#      end
-#    end
-
     @@utils.getImage.saveImage
   end
-
-
-# Need to properly sever this at some point...
-
-  def decode
-puts "Hacked in decode..."
-    s = @@utils.getImage.getSize
-
-    msg_bits = 0
-
-    @@table.reverse.each do |loc|
-      pixel = @@utils.getImage.getPixel(loc[:x], loc[:y])
-      msg_bits = (msg_bits << 6) | pixel.decodeBits
-    end
-
-#this trash needs to move somewhere...
-puts "Try to convert the message..."
-    len = msg_bits & 0xffff
-    msg_bits = msg_bits >> 16
-
-    # check the padding bits....
-    if (msg_bits & 255) != 0 then
-puts "Padding failed scrutiny! "
-puts msg_bits.to_s(2)
-      return false
-    end
-
-    msg_bits = msg_bits >> 8
-
-puts "Padding passed scrutiny..."
-    msg_chars = []
-
-    while msg_bits > 0 do
-      byte = msg_bits & 0xff
-      msg_chars.push(byte.chr)
-      msg_bits = msg_bits >> 8
-    end
-
-    msg = msg_chars.reverse.join
-
-    return msg
-  end
 end

image_utils.rb

@@ -1,76 +1,116 @@
-require "./pixel_image.rb"
+require "rmagick"
 require "digest"
 
 class ImageUtils
   @@magickImg  = nil
-  @@pixelImg = nil
 
   @@password   = ""
   @@message    = ""
+  @@salt       = 0
+
+  @@imagickImg = nil
+
+  @@width      = 0
+  @@height     = 0
+
+  @@pixel_arr  = nil
 
   @@hash       = nil
 
-  def initialize(pass, msg, i)
+  @@rng        = nil
+
+  def initialize(pass, msg, uri)
     @@password = pass
     @@message  = msg
+    @@salt     = 0
 
-    if msg.length > 400 then
-      puts "Maximum length exceeded.  Exiting."
-      exit
+    @@magickImg = Magick::Image.read(uri).first
+
+    @@width = @@magickImg.columns
+    @@height = @@magickImg.rows
+
+    @@pixel_arr = @@magickImg.get_pixels(0, 0, @@width, @@height)
+
+    @@hash = self.generateHash
+
+    # convert hex string into an int to store for making the lookup table
+    @@rng = Random.new(@@hash.to_i(16))
+
+    puts self.getLookupTable.inspect
   end
 
-    @@magickImg = i
+  def getPixel(x, y)
+    loc = (y*@@width) + x
 
-    @@pixelImg = PixelImage.new(@@magickImg)
-
-    self.generateHash
+    return @@pixel_arr[loc]
   end
 
-  def getImage
-    return @@pixelImg
+  def getSalt
+    for x in 0..@@width-1
+      for y in 0..@@height-1
+        pix = self.getPixel(x, y)
+
+        @@salt = @@salt + (pix.red/512)
+        @@salt = @@salt + (pix.green/512)
+        @@salt = @@salt + (pix.blue/512)
+      end
+    end
+
+    h = Digest::SHA512.hexdigest(@@salt.to_s(16))
+
+    return h
   end
 
   def generateHash
-    h = Digest::SHA512.hexdigest(@@password)
-    s = @@pixelImg.getSalt
+    pass_h = Digest::SHA512.hexdigest(@@password)
 
-    merge_to_i = h + s
-
-    @@hash = Digest::SHA512.hexdigest(h+s)
+    return Digest::SHA512.hexdigest(pass_h + @@salt.to_s)
   end
 
-  def generateLookupTable
+  def getBits(o)
+    msg_bytes = o.unpack("c*")
+
+    msg_bits = 0
+
+    for b in msg_bytes
+      msg_bits = (msg_bits << 8) | b
+    end
+
+    return msg_bits
+  end
+
+  def getLookupTable
     tbl = []
 
-    hash_bits = @@pixelImg.getBits(@@hash)
-    msg_bits = @@pixelImg.getBits(@@message)
+    # track hash classes.  if too many occur during the interval, abaondon 
+    # encoding.
+    clashes = 0
+    clash_limit = 100
 
-    # gross, but pad in the 24 bits that will become the msg length
-    # and padding bits...
-    msg_bits = msg_bits << 24
+    msg_bits = self.getBits(@@message)
  	
     while msg_bits > 0 do
       loc = nil
 
       loop do
-        x = (hash_bits.to_i % @@pixelImg.getSize[:width])
-        y = (hash_bits.to_i % @@pixelImg.getSize[:height])
+        x = @@rng.rand(0..@@width)
+        y = @@rng.rand(0..@@height)
 
         loc = {"x": x, "y": y}
+        if !tbl.include?(loc) then
+          clashes = 0
+        else
+          clashes = clashes + 1
+        end
 
-      break if !tbl.include?(loc)
-        hash_bits = hash_bits >> 1
-
-        if hash_bits <= 0 then
-          puts
-          puts "wow too much data"
-          puts "leftover bits: " + msg_bits.to_s(36)
+        if clashes < clash_limit then
+          break
+        else
+          puts "wow clashed so much sorry for breaking"
           exit
         end
       end
 
-      hash_bits = hash_bits >> 1
-
       tbl.push(loc)
 
       msg_bits = msg_bits >> 6
@@ -78,4 +118,16 @@ class ImageUtils
 
     return tbl
   end
+
+  def getBits(o)
+    msg_bytes = o.unpack("c*")
+
+    msg_bits = 0
+
+    for b in msg_bytes
+      msg_bits = (msg_bits << 8) | b
+    end
+
+    return msg_bits
+  end
 end

runner.rb

@@ -1,14 +1,19 @@
-require "rmagick"
-
 require "./image_utils.rb"
 require "./encode_image.rb"
 
-img = Magick::ImageList.new "./images/original/arty_2.jpg"
-
 #srand(12345)
 
 pass = "my_password"
+
 message = "This is the message that I would like to save please " +
+          "and thank you also I love you? AND apostrophe's, and " +
+          "also some commas somewhere hiding around here,  It's " +
+          "gonna be pushing it a bit here... 1234567 let's huck " + 
+          "some more stuff in here to bump it to 255.  Wow.  We " +
+          "are going even further.  further than anyone believed " +
+          "`~!@\#\{$%^&*()-_=+\][}{';:'}]} Wooow. 123456789!1234" +
+          "56789! so put 15 more??????400! TIMES TWO!! " + 
+          "This is the message that I would like to save please " +
           "and thank you also I love you? AND apostrophe's, and " +
           "also some commas somewhere hiding around here,  It's " +
           "gonna be pushing it a bit here... 1234567 let's huck " + 
@@ -16,17 +21,21 @@ message = "This is the message that I would like to save please " +
           "are going even further.  further than anyone believed " +
           "`~!@\#\{$%^&*()-_=+\][}{';:'}]} Wooow. 123456789!1234" +
           "56789! so put 15 more??????400!"
-#message = "tests"
 
 puts message.length
 puts message
 puts
 
-puts "Initializing EncodeImage..."
-
 start = Time.new.to_f
 
-em = EncodeImage.new(pass, message, img)
+puts "Initializing EncodeImage..."
+
+iu = ImageUtils.new(pass, message, "./images/original/arty.png")
+
+puts "Took " + (Time.new.to_f - start).to_s + " seconds to encode... 🐱"
+
+=begin
+em = EncodeImage.new(pass, message, "./images/original/arty.png")
 
 puts em.encode
 puts "Took " + (Time.new.to_f - start).to_s + " seconds to encode... 🐱"
@@ -38,13 +47,12 @@ result = em.decode
 
 puts result
 
+=end
+
 puts "Took " + (Time.new.to_f - start).to_s + " seconds to decode... 🐱"
 
 if message == result then
   puts "WOW THEY MATCH! 🐱🐱🐱🐱🐱🐱🐱🐱"
 end
 
-exit  
-puts
-
 puts "Done!"