Watermarking digital content

Patent metadata

Field	Value
Publication number	US-11113780-B2
Application number	US-201916978577-A
Country	US
Kind code	B2
Filing date	Feb 11, 2019
Priority date	Apr 6, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

Examples relating to watermarking digital content are described herein. According to one example, a digital quality of digital content received for watermarking is determined. From a library of watermark tints comprising a plurality of preformed watermark tints of predefined sizes, a watermark tint set for watermarking the digital content is retrieved, the watermark tint set comprising a plurality of watermark tints having a first size. The first size of the plurality of watermark tints is determined based on the digital quality of the digital content. The plurality of watermark tints having the first size are overlaid over the digital content to watermark the digital content.

First claim

I claim:

1. A method comprising:
determining a digital quality of digital content received for watermarking;
retrieving, from a library of watermark tints comprising a plurality of preformed watermark tints of predefined sizes, a watermark tint set for watermarking the digital content, the watermark tint set comprising a plurality of watermark tints having a first size, wherein the first size of the plurality of watermark tints is determined based on the digital quality of the digital content; and
overlaying the plurality of watermark tints of the first size over the digital content to watermark the digital content.

2. The method as claimed in claim 1 , wherein the retrieving comprises creating the library of watermark tints, the creating comprising:
generating a grayscale image of a white template image;
applying histogram compression to the generated grayscale image to obtain a compressed image; and
inverting a colour of the compressed image to obtain a transparent image.

3. The method as claimed in claim 2 , further comprising:
dividing the transparent image into a plurality of ties of the first size to obtain a watermark tint; and
creating the watermark tint set having a predetermined number of watermark tints of the first size therein.

4. The method as claimed in claim 3 , wherein the creating comprises associating a payload ID with the watermark tint.

5. The method as claimed in claim 1 , wherein the retrieving comprises:
determining a highest common divisor of a resolution associated with the digital content; and
selecting the first size based on the determining.

6. The method as claimed in claim 1 , wherein the overlaying comprises marking a payload ID associated with each of the plurality of preformed watermark tints as used.

7. The method as claimed in claim 1 , wherein the overlaying comprises marking a payload ID associated with each of the plurality of preformed watermark tints as reserved when the plurality of tints is selected for overlaying.

8. The method as claimed in claim 1 , wherein the overlaying comprises embedding user identification parameters in each of the plurality of watermark tints.

9. A watermarking system ( 102 ) comprising:
a selection engine ( 204 ) to,
determine a digital quality of a digital content received for watermarking;
ascertain a size and a number of preformed watermark tints for watermarking the digital content, based on the digital quality of the digital content;
retrieve a watermark tint set from a library of watermark tints, the watermark tint set comprising the ascertained number of preformed watermark tints of the ascertained size; and

a watermarking engine ( 206 ) to overlay the retrieved preformed watermark tints in the watermark tint set over the digital content to watermark the digital content.

10. The watermarking system ( 102 ) as claimed in claim 9 , further comprising a library creation engine ( 214 ) to:
generate a grayscale image of a white template image;
compress the generated grayscale image using histogram compression technique;
invert a colour of the compressed image to obtain a transparent image; and
divide the transparent image into a plurality of tiles, each tile forming a preformed watermark tint.

11. The watermarking system ( 102 ) as claimed in claim 10 , wherein the library creation engine ( 214 ) is to create a watermark tint set of a first size having a predetermined number of tiles of the first size.

12. The watermarking system ( 102 ) as claimed in claim 10 , wherein the library creation engine ( 214 ) is to associate a payload ID with each watermark tint.

13. The watermarking system ( 102 ) as claimed in claim 9 , wherein the selection engine ( 204 ) is to:
determine a highest common divisor of a resolution associated with the digital content; and
ascertain the size and the number of the watermark tints based on the highest common divisor of the resolution.

14. A non-transitory computer-readable medium ( 502 ) comprising instructions executable by a processing resource ( 504 ) of a device to:
determining one of an aspect ratio (x:y) and a resolution (x, y) of digital content received for watermarking;
ascertain a size and a number of preformed watermark tints to watermark the digital content based on a highest common divisor of x and y, each preformed watermark tint formed by generating a transparent format of a white template image using histogram compression technique and dividing the transparent image into a plurality of tiles of different sizes;
select, based on the highest common divisor, a watermark tint set comprising the ascertained number of preformed watermark tints of the ascertained size; and
overlay the preformed watermark tints in the watermark tint set over the digital content to watermark the digital content.

15. The non-transitory computer-readable medium ( 502 ) as claimed in claim 14 , further comprising instructions executable by the processing resource ( 504 ) to:
associate a payload ID with each preformed watermark tint;
mark the payload ID associated the preformed watermark tint as used when the preformed watermark tint is overlaid; and
mark the payload ID associated with the preformed watermark tint as reserved when preformed watermark tint is selected for overlaying.

Assignees

• Hewlett Packard Development Co

Inventors

• Kumar Amrendra

Classifications

• H04N21/8358 Primary

  involving watermark {(protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467)} · CPC title

• H04N1/32208

  involving changing the magnitude of selected pixels, e.g. overlay of information or super-imposition (H04N1/32219, H04N1/32224 take precedence) · CPC title

• H04N21/8352

  involving content or source identification data, e.g. Unique Material Identifier [UMID] · CPC title

• G06T1/0028 Primary

  Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking · CPC title

• H04N1/32277

  Compression · CPC title