摘要:
A system for creating a data-bearing image can include a reference image generator configured to apply a clustered-dot halftone screen to a continuous-tone image. The resulting reference halftone image includes carrier cells in which a pixel cluster can be shifted to at least two shift positions in the carrier cell. The system also includes a payload encoder configured to segment the data payload and encode data segments into one of the carrier cells by shifting the cluster to one of the shift positions. The system also includes an output device configured to output the resulting data-bearing halftone image.
摘要:
Document copying systems and methods include initiating a copy job (20) for copying a document (1) having document content. A log (22) of the copy job is generated, and the document is scanned to create a document content image (24). The log is encoded using an input image to produce a data-bearing halftone image (26) which is merged with the document content image (28). The merged data-bearing halftone image and the document content image are printed (30) to produce a copy (2) of the document.
摘要:
A forensic verification system (700) extracts a print signature via print signature extractor 710 from the boundary of a halftone contained in an image. The system (700) compares the print signature to a reference signature stored in a registry via comparator 720 to determine differences between the print signature and the reference signature. The system 700 performs a forensic-level statistical image analysis via forensic analyzer 730 on the print signature and the reference signature based on the comparison to authenticate the printed media.
摘要:
A payload recovery system includes a reference halftone image of a data-bearing halftone image and a reference map of the data-bearing halftone image. The system further includes a cell alignment system for receiving a scanned image of a hard copy of the data-bearing halftone image and for generating an aligned scan of the scanned image using the reference halftone image and the reference map. A raw payload recovery system determines possible shift positions of each carrier cell of the aligned scan using a shift rule and the reference map; and a reconstructed data-bearing halftone image is generated by the raw payload recovery system using the possible shift positions and the reference halftone. The system also includes a recovered raw payload generated by the raw payload recovery system using the shift rule and the reference map.
摘要:
Methods and systems are provided for tracing the source of a printed document. A method may include receiving a print job for printing a page having page content, generating a log of the print job, encoding the log using a mule image to produce a data-bearing halftone image, merging the data-bearing halftone image with the page content, and printing the merged data-bearing halftone image and page content to produce a printed document.
摘要:
Methods and systems are provided for tracing the source of a printed document. A method may include receiving a print job for printing a page having page content, generating a log of the print job, encoding the log using a mule image to produce a data-bearing halftone image, merging the data-bearing halftone image with the page content, and printing the merged data-bearing halftone image and page content to produce a printed document.
摘要:
Candidate redeye areas (24) are determined in an input image (20). In this process, a respective set of one or more redeye metric values (28) is associated with each of the candidate redeye areas (24). Candidate face areas (30) are ascertained in the input image (20). In this process, a respective set of one or more face metric values (34) is associated with each of the candidate face areas (30). A respective joint metric vector (78) is assigned to each of the candidate redeye areas (24). The joint metric vector (78) includes metric values that are derived from the respective set of redeye metric values (28) and the set of face metric values (34) associated with a selected one of the candidate face areas (30). Each of one or more of the candidate redeye areas (24) is classified as either a redeye artifact or a non-redeye artifact based on the respective joint metric vector (78) assigned to the candidate redeye area (24).
摘要:
An example provides a system and method of robust alignment and payload recovery for data-bearing images. The method includes digitizing a printed version of a stegatone, computing the transformation parameters of the stegatone, and processing individual local regions of the stegatone to determine local transformation parameters. The method also includes performing an alignment evaluation to compute a metric value that represents the quality of a local alignment between a reference halftone and the stegatone. Further, the method includes selecting alignment parameters based on optimization of the metric value, mapping the shift of clustered-dots in each cell in comparison to the reference halftone, and recovering the payload by decoding the stegatone.
摘要:
Candidate redeye areas (24) are determined in an input image (20). In this process, a respective set of one or more redeye metric values (28) is associated with each of the candidate redeye areas (24). Candidate face areas (30) are ascertained in the input image (20). In this process, a respective set of one or more face metric values (34) is associated with each of the candidate face areas (30). A respective joint metric vector (78) is assigned to each of the candidate redeye areas (24). The joint metric vector (78) includes metric values that are derived from the respective set of redeye metric values (28) and the set of face metric values (34) associated with a selected one of the candidate face areas (30). Each of one or more of the candidate redeye areas (24) is classified as either a redeye artifact or a non-redeye artifact based on the respective joint metric vector (78) assigned to the candidate redeye area (24).
摘要:
An example provides a system and method of robust alignment and payload recovery for data-bearing images. The method includes digitizing a printed version of a stegatone, computing the transformation parameters of the stegatone, and processing individual local regions of the stegatone to determine local transformation parameters. The method also includes performing an alignment evaluation to compute a metric value that represents the quality of a local alignment between a reference halftone and the stegatone. Further, the method includes selecting alignment parameters based on optimization of the metric value, mapping the shift of clustered-dots in each cell in comparison to the reference halftone, and recovering the payload by decoding the stegatone.