Protecting images with image markings

A method for generating a watermarked image wherein a watermark is imparted onto a digitized image having a plurality of original elements having original brightnesses, said method comprising the steps of:

• providing a digitized watermarking signal comprising a plurality of watermarking elements, each having a watermark brightness adjusting factor and having correspondence with said original elements;
• and
• producing a watermarked image by adjusting said original brightness of each of said original elements corresponding to one of said watermark elements, the brightness adjusting factor being computed from the digitized image such that the adjusting is imperceptible.

A method for generating a watermarked image wherein a watermark is imparted onto a digitized image having a plurality of original elements having original brightnesses, said method comprising the steps of:

• providing a digitized watermarking signal comprising a plurality of watermarking elements, each having a watermark brightness adjusting factor and having correspondence with said original elements;
• and
• producing a watermarked image by adjusting said original brightness of each of said original elements corresponding to one of said watermark elements, wherein said watermark is invisible, said original image forms an original plane, said watermarking signal corresponds to locations in an area smaller than the digitized image and is produced by employing a Difference of Averages technique.

A method for imparting a watermark onto a digitized image, said method comprising:

• providing a digitized image, said image being represented by an image array having a plurality of pixels, said pixels having at least one color component, said watermark being formed using a distinct watermarking signal represented by an array having a plurality of distinct watermarking elements, each of said distinct watermarking elements having an array position and having positional correspondence with said image pixels, and multiplying said brightness data associated with said at least one color component by an adjustment factor, wherein said adjustment factor relates to a corresponding distinct watermarking element, and said watermark has an invisibility classification.

A method of embedding a watermark into a digital color image, wherein said image has I rows and J columns, and has a pixel in row i and column j having at least one brightness, Y(i, j), the method comprising:

• generating a watermark signal based on a random number;
• and
• altering the digital color image to embed the watermark in the color image, including adding to or subtracting from the brightness Y(i, j) corresponding elements of the watermark signal, wherein 1 is less than or equal to i is less than or equal to I and 1 is less than or equal to j is less than or equal to J are the row and column indices of a pixel location in the image.

A method for imparting a watermark onto a digitized image comprising the steps of:

• providing said digitized image comprised of a plurality of pixels, wherein each of said pixels inchides brightness data that represents a brightness of at least one color, with said image having I rows and J columns, and pixel in row i and column j having a brightness Y(i, j);
• and for a plurality i and at least one j adding to or subtracting from the brightness Y(i, j) a value, wherein 1 is less than or equal to i is less than or equal to I and 1 is less than or equal to j is less than equal to J are the row and column indices of a pixel location in the image, and wherein the value is an element in a watermark signal generated with a random signal.

A method for generating a watermarked image, the method comprising:

• imparting a watermark onto a digitized image having a plurality of original pixels, each of said pixels having at least one original pixel brightness value;
• providing said watermark comprising a plurality of watermarking elements, each element having a watermark brightness adjustment and having a positional correspondence with said original pixels;
• and producing a watermarked image by multiplying said original brightness of each of said original pixels by an adjustment factor of a corresponding one of said watermark elements.

A method for imparting a watermark pattern onto a digitized image comprising the steps of:

• providing said digitized image comprised of a plurality of image pixels with said digitized image having I rows and J columns, and a pixel in row i and column j having at least one component, Y(i, j);
• and adding to or subtracting from said brightness data associated with at least one of said pixels a predetermined brightness adjustment in the range of 0 to Y(i, j), wherein said watermark pattern has a relationship with a random number.

A method of hiding a code in a signal representing image data, said method comprising:

• selecting positions in the signal for hiding the code based at least in part on predetermined criteria;
• and
• adjusting at least one value corresponding to the signal at or around a selected position to hide the code based at least in part on one or more values corresponding to the signal at or around the selected position, wherein redundant instances of the code are hidden in the signal at or around the selected positions.