1. An electronic system for inserting a watermark into a digital image, comprising: a means for modifying at least one predetermined bit in an image block X r, wherein the modified image block is X r ; a means for calculating a digest of values using a cryptographic hash function, wherein the means for calculating a digest of value outputs a hashed output, wherein the means for modifying at least one predetermined bit of the image block is electrically coupled to the means for calculating a digest of values; a means for combining the hashed output with a watermark, wherein the means for combining the hashed output with a watermark is electrically coupled to the means for calculating a digest of values, wherein the output of the means for combining is a combined image block; and a means for inserting the combined image block (C r ) into the modified image block X r, wherein the means for inserting the combined image block (C r ) into the modified image block X r is electrically coupled to the means for modifying at least one predetermined bit of the image block.