37. An electronic mail (email) security system comprising: a non-transitory storage device having tangibly embodied thereon instructions associated with an anti-spam module; and one or more processors coupled to the non-transitory storage device and operable to execute the instructions associated with the anti-spam module to perform a method comprising: converting an embedded image of an email message to a binarized representation by performing thresholding on a grayscale representation of the embedded image; quantifying a number of text strings that are included in the embedded image by analyzing one or more blocks of the binarized representation with a text string measurement algorithm; classifying the email message as spam or clean based at least in part on the number of text strings; and wherein the one or more blocks comprise M×N virtual blocks and wherein the text string measurement algorithm employs equations having a general form as follows: T = ∑ m = 0 M ⁢ ∑ n = 0 N ⁢ T m , n subject ⁢ ⁢ to ⁢ : T m , n = ∑ y t = y 0 m y max m ⁢ ∑ y b = y t + 1 y max m ⁢ T y t , y b m , n y 0 m = y max ∂ 0 ⁢ ( m - 1 ) , y max m = y 0 m + ∂ 0 ⁢ ⁢ T y t , y b m , n = { 1 ∂ 1 ⁢ > ∑ i = y t y b ⁢ CB i n > ∂ 2 ∑ k = x 0 n x max n ⁢ B k , y b + 1 < ∂ 3 , x 0 n = x max ∂ 0 ⁢ ( n - 1 ) , x max n = x 0 n + ∂ 0 0 Otherwise ⁢ ⁢ CB i n = { 1 ∂ 4 ⁢ > ∑ k = x 0 n x max n ⁢ B k , i > ∂ 5 Max ⁡ ( ∑ k = x w x w + ∂ 6 ⁢ B k , i ) < ∂ 7 , x 0 n ≤ x w ≤ x max n 0 Otherwise where, ∂ 0 . . . ∂ 7 are adjustable parameters; T is the number of text strings; T y t ,y b m,n is a likelihood that a row between y t and y b in virtual block [m,n] represents text; CB i n is a likelihood that a line[i] is a part of text; and B k,i is a value of pixel[k,i] in the binary representation.
37. An electronic mail (email) security system comprising: a non-transitory storage device having tangibly embodied thereon instructions associated with an anti-spam module; and one or more processors coupled to the non-transitory storage device and operable to execute the instructions associated with the anti-spam module to perform a method comprising: converting an embedded image of an email message to a binarized representation by performing thresholding on a grayscale representation of the embedded image; quantifying a number of text strings that are included in the embedded image by analyzing one or more blocks of the binarized representation with a text string measurement algorithm; classifying the email message as spam or clean based at least in part on the number of text strings; and wherein the one or more blocks comprise M×N virtual blocks and wherein the text string measurement algorithm employs equations having a general form as follows: T = ∑ m = 0 M ⁢ ∑ n = 0 N ⁢ T m , n subject ⁢ ⁢ to ⁢ : T m , n = ∑ y t = y 0 m y max m ⁢ ∑ y b = y t + 1 y max m ⁢ T y t , y b m , n y 0 m = y max ∂ 0 ⁢ ( m - 1 ) , y max m = y 0 m + ∂ 0 ⁢ ⁢ T y t , y b m , n = { 1 ∂ 1 ⁢ > ∑ i = y t y b ⁢ CB i n > ∂ 2 ∑ k = x 0 n x max n ⁢ B k , y b + 1 < ∂ 3 , x 0 n = x max ∂ 0 ⁢ ( n - 1 ) , x max n = x 0 n + ∂ 0 0 Otherwise ⁢ ⁢ CB i n = { 1 ∂ 4 ⁢ > ∑ k = x 0 n x max n ⁢ B k , i > ∂ 5 Max ⁡ ( ∑ k = x w x w + ∂ 6 ⁢ B k , i ) < ∂ 7 , x 0 n ≤ x w ≤ x max n 0 Otherwise where, ∂ 0 . . . ∂ 7 are adjustable parameters; T is the number of text strings; T y t ,y b m,n is a likelihood that a row between y t and y b in virtual block [m,n] represents text; CB i n is a likelihood that a line[i] is a part of text; and B k,i is a value of pixel[k,i] in the binary representation. 38. The system of claim 37 , wherein the embedded image is conveyed formatted in accordance with Graphic Interchange Format (GIF), Joint Photographic Experts Group (JPEG) or Portable Network Graphics (PNG).