Watermarking a page description language file

• US 20030142361A1
• Filed: 01/30/2002
• Published: 07/31/2003
• Est. Priority Date: 01/30/2002
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Walton, Scott E.
• Granted Patent: US 6,899,475 B2
• Time in Patent Office: Days
• US Class Current: 358/3.28
• CPC Class Codes: H04N 1/32144 embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
• CPC Class Codes: H04N 1/32267 combined with processing of the image
• CPC Class Codes: H04N 2201/0067 Converting to still picture data
• CPC Class Codes: H04N 2201/0068 Converting from still picture data
• CPC Class Codes: H04N 2201/3271 Printing or stamping

Abstract

The present invention provides a method and system for watermarking a file which is in a PDL such as PostScript. The present invention can be used to either watermark a PDL file and then generate a watermarked PDL file or the present invention can be part of the Interpreter in a printer which takes a file in a PDL and which then generates watermarked raster images which are printed.

The present invention includes an “interpreter” which generates raster images from the PDL file. The raster images are then watermarked using conventional watermarking techniques. Next the raster images are either printed (if the interpreter is part of a printer) or the raster images are combined into a new PDL file.

Claims

1. ) a method of watermarking a file which is in a page description language (DPL) comprising,

interpreting said PDL file and generating a set of raster images,

watermarking each of said raster images individually,

combining the watermarked raster images into a second PDL file,

interpreting said second file using a interpreter to generate a second set of raster

images, and

printing said second set of raster images.

2. ) The method recited in claim 1 wherein said PDL is PostScript.

3. ) The method recited in claim 1 wherein a mask is used to determine which areas of said raster images are watermarked.

10. ) The method recited in claim 1 where said interpreters are the Gostscript interpreter.

17. ) The method in claim 1 wherein said set comprises four raster images.

4. ) A system for watermarking a file which is in a page description language (PDL) comprising,

an interpreter for interpreting said file and for generating a set of raster images,

a watermarking program for watermarking each of said raster images individually,

a compiler for combining said watermarked raster images into a second PDL file,

an interpreter for interpreting said second PDL file and generating second set of

raster images, and

printing said second set of raster images.

5. ) The system recited in claim 4 wherein said PDL is PostScript.

6. ) The system recited in claim 4 where wherein a mask is used to determine which areas of said raster images are watermarked.

11. ) The system recited in claim 4 where said interpreters are the Gostscript interpreter

7. ) A method of watermarking a file which is in a page description language (PDL) comprising,

interpreting said PDL file and generating a set of raster images,

watermarking each of said raster images individually,

printing said raster images.

8. ) The method recited in claim 7 wherein said PDL is PostScript.

9. ) The method recited in claim 7 wherein a mask is used to determine which areas of said raster images are watermarked.

12. ) The method recited in claim 7 where said interpreters are the Gostscript interpreter

13. ) A system for watermarking a file which is in a page description language (PDL) comprising,

an interpreter for interpreting said PDL file and generating a plurality of raster images,

a watermarking program for watermarking each of said raster images individually and,

a printer for printing said raster images.

14. ) The system recited in claim 13 wherein said PDL is PostScript.

15. ) The system recited in claim 13 where wherein a mask is used to determine which areas of said raster images are watermarked.

16. ) The system recited in claim 13 wherein said interpreter is the Gostscript interpreter.