1. A method of encoding information in text documents, the method comprising: obtaining a text document having dimensions and at least a first character and a second character; determining a length between the first character and the second character to define an inter-character space; determining a reference length, the reference length being a function of the dimensions; determining a threshold length, the threshold length being a minimum length wherein information is not encoded in the inter-character space when the inter-character space is less than the threshold length; encoding the information into an altered inter-character space wherein a length of the altered inter-character space is an integral multiple of the reference length or a non-integral multiple of the reference length; and determining whether the length of the altered inter-character space is within a threshold margin, wherein the threshold margin is a predetermined minimum length on both sides of the threshold length to define a lower threshold margin and an upper threshold margin.
1. A method of encoding information in text documents, the method comprising: obtaining a text document having dimensions and at least a first character and a second character; determining a length between the first character and the second character to define an inter-character space; determining a reference length, the reference length being a function of the dimensions; determining a threshold length, the threshold length being a minimum length wherein information is not encoded in the inter-character space when the inter-character space is less than the threshold length; encoding the information into an altered inter-character space wherein a length of the altered inter-character space is an integral multiple of the reference length or a non-integral multiple of the reference length; and determining whether the length of the altered inter-character space is within a threshold margin, wherein the threshold margin is a predetermined minimum length on both sides of the threshold length to define a lower threshold margin and an upper threshold margin. 8. The method according to claim 1 , wherein the dimensions include a height of the text document, and the reference length is a predetermined percentage of the height of the text document.