摘要:
A background pattern image combining apparatus for combining a background pattern image with an input image is provided. The background pattern image includes a plurality of first isolated points having a size that can be read by an image reader and a plurality of second isolated points having a size that cannot be read by the image reader. The background pattern image combining apparatus includes a detector that detects, in the input image, a specific area which is an area having a specific state, and a combining portion that combines the background pattern image with the input image by placing not the plurality of first isolated points but the plurality of second isolated points in the specific area, and, by placing the plurality of first isolated points and the plurality of second isolated points in an area other than the specific area.
摘要:
Methods are provided for encoding watermark information into media data containing a series of digital samples in a sample domain. The method involves: dividing the series of digital samples into a plurality of sections in the sample domain, each section comprising a corresponding plurality of samples; processing the corresponding plurality of samples in each section to obtain a single energy value associated with each section; grouping the sections into groups, each group containing three or more sections; assigning a nominal bit value to each group according to a bit assignment rule, the bit assignment rule based on the energy values of the sections in the group; and assigning a watermark bit value to each group. The methods also involve, for each group, comparing the watermark bit value to the nominal bit value and, if the nominal bit value and the watermark bit value of the watermark information bit do not match, modifying one or more energy values of one or more corresponding sections in the group such that re-application of the bit assignment rule would assign the watermark bit value to the group. The bit assignment rule may comprise: a categorization rule for categorizing each group into one of a plurality of categories; and for each category, a unique category bit assignment rule for assigning a nominal zero bit value or a nominal one bit value to each group.
摘要:
Watermarking a projected image for rendering a digital presentation with a watermark coding. The watermark coding uniquely identifies the source of the image presentation. The watermark coding includes a set of images wherein each image defines a watermark image. The images include dots which uniquely define each image relative to the other images in the set by at least an angular relationship between dots of the image.
摘要:
Improved techniques for making copy detection patterns (105) and using them to detect copying relationships between digital representations. The techniques include techniques for including a message in a copy detection pattern (105) without altering the copy detection patterns entropy and reading the message, techniques for using a copy detection pattern on an analog form to determine whether the analog form is an original analog form without reference to a digital representation of the original of the analog form's copy detection pattern, techniques for increasing the sensitivity of copy detection using copy detection patterns by modifying one of two copy detection patterns that are being compared to take into account alterations resulting from the copying process, techniques for distributing a copy detection pattern across a document, and techniques for using the entropy of a copy detection pattern to locate the copy detection pattern. Also disclosed are applications of copy detection patterns with copying that involves transformations between the digital and analog forms and with digital-to-digital copying.
摘要:
Das Verfahren zum Einbetten von binärer Wasserzeicheninformation in Vektorschriftzeichen, die unter anderem durch Linien definiert sind, welche jeweils eine Breite aufweisen, wobei die Linien der Vektorschriftzeichen in Linienbreitengruppen unterschiedlicher, jeweils durch einen unteren und einen oberen Grenzwert definierter Breitenbereiche unterteilt sind, umfasst die folgenden Schritte: a) zufälliges oder pseudozufälliges Auswählen von zwei Linien eines Vektorschriftzeichens oder je einer Linie zweier Vektorschriftzeichen mit zu einer gemeinsamen Linienbreitengruppe gehörenden Breiten, b) Definieren der einen Linie als erste Linie und der anderen Linie als zweite Linie, und c) Verändern des Breitenverhältnisses der beiden Linien derart, dass die erste Linie breiter ist als die zweite Linie und beide Linien jeweils eine Breite aufweisen, die innerhalb des Breitenbereichs der Linienbreitengruppe liegt, wodurch eine erste binäre Wasserzeicheninformation in das bzw. in die Vektorschriftzeichen eingebettet wird oder d) Verändern des Breitenverhältnisses der beiden Linien derart, dass die erste Linie schmaler ist als die zweite Linie und beide Linien jeweils eine Breite aufweisen die innerhalb des Breitenbereichs der Linienbreitengruppe liegt, wodurch eine zweite binäre Wasserzeicheninformation in das bzw. in die Vektorschriftzeichen eingebettet wird.
摘要:
Improved techniques for making copy detection patterns and using them to detect copying relationships between digital representations. The techniques include techniques for including a message in a copy detection pattern without altering the copy detection patterns entropy and reading the message, techniques for using a copy detection pattern on an analog form to determine whether the analog form is an original analog form without reference to a digital representation of the original of the analog form's copy detection pattern, techniques for increasing the sensitivity of copy detection using copy detection patterns by modifying one of two copy detection patterns that are being compared to take into account alterations resulting from the copying process, techniques for distributing a copy detection pattern across a document, and techniques for using the entropy of a copy detection pattern to locate the copy detection pattern. Also disclosed are applications of copy detection patterns with copying that involves transformations between the digital and analog forms and with digital-to-digital copying.