QUALITY CHECKS FOR PRINTED PAGES USING TARGET IMAGES THAT ARE GENERATED EXTERNAL TO A PRINTER

• US 20140056484A1
• Filed: 08/21/2012
• Published: 02/27/2014
• Est. Priority Date: 08/21/2012
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Lotz, Michael, Dennison, Carl
• Granted Patent: US 9,143,628 B2
• Time in Patent Office: Days
• US Class Current: 382/112
• CPC Class Codes: H04N 1/00 Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
• CPC Class Codes: H04N 1/00047 using an image not specifically designed for the purpose
• CPC Class Codes: H04N 1/0005 in service, i.e. during normal operation
• CPC Class Codes: H04N 1/00074 Indicating or reporting details of user-machine interface H04N1/0035

Abstract

Systems and methods are provided for ensuring that printed output for a print job matches the expected output for a print job. The system comprises a control unit and a comparison unit. The control unit receives a print job and modifies the print job by adding a tag to each logical page of the print job, and to transmit the modified print job to a printer. The control unit further generates target images for the logical pages of the print job. The comparison unit receives printed pages of the job from the printer. For each printed page of the job, the comparison unit identifies a tag on the printed page, identifies a target image corresponding with the tag on the printed page, and compares an image of the printed page to the target image to detect discrepancies between the printed page and the target image.

Claims

1. A system comprising:

a control unit operable to receive a print job, to modify the print job by adding a tag to each logical page of the print job, and to transmit the modified print job to a printer, the control unit further operable to generate target images for the logical pages of the print job; and

a comparison unit operable to receive printed pages of the job from the printer, and for each printed page of the job, to;

identify a tag on the printed page;

identify a target image corresponding with the tag on the printed page; and

compare an image of the printed page to the target image to detect discrepancies between the printed page and the target image.

2. The system of claim 1 wherein:

the control unit is further operable to add tags to the logical pages that distinguish the printed pages from each other.

3. The system of claim 1 wherein:

the control unit is further operable to generate target images that each comprise a bitmap representing a logical page of the print job.

4. The system of claim 1 wherein:

the comparison unit is further operable to detect discrepancies on a printed page where a group of printed pels does not match a group of expected pels defined in a target image.

5. The system of claim 1 wherein:

the control unit comprises a print server coupled with the printer and the comparison unit.

6. The system of claim 1 wherein:

the control unit is further operable to add the tags to a portion of each logical page that will be removed from corresponding printed pages of the print job after printing.

7. The system of claim 1 wherein:

the control unit is further operable to receive information from the comparison unit indicating the discrepancies, and to generate a prompt at a user interface informing a user of the detected discrepancies.

8. A method comprising:

receiving a print job at a control unit of a printing system;

modifying the print job by adding a tag to each logical page of the job at the control unit;

transmitting the modified print job from the control unit to a printer;

generating target images for the logical pages of the print job at the control unit;

receiving printed pages of the job from the printer at a comparison unit; and

for each printed page;

identifying a tag on the printed page;

identifying a target image corresponding with the tag on the printed page; and

comparing an image of the printed page to the target image to detect discrepancies between the printed page and the target image.

9. The method of claim 8 wherein modifying the print job comprises:

adding tags that distinguish the printed pages from each other.

10. The method of claim 8 wherein generating the target images comprises:

generating target images that each comprise a bitmap representing a logical page of the print job.

11. The method of claim 8 wherein comparing the image of the printed page to the target image comprises:

detecting discrepancies on the printed page where a group of printed pels does not match a group of expected pels defined in the target image.

12. The method of claim 8 wherein:

the control unit comprises a print server coupled with the printer and the comparison unit.

13. The method of claim 8 wherein modifying the print job comprises:

adding the tags to a portion of each logical page that will be removed from corresponding printed pages of the print job after printing.

14. The method of claim 8 further comprising:

receiving information from the comparison unit indicating the discrepancies detected at the control unit; and

generating a prompt at a user interface of the control unit informing a user of the detected discrepancies.

15. A non-transitory computer readable medium embodying programmed instructions which, when executed by a processor, are operable for performing a method comprising:

receiving a print job at a control unit of a printing system;

modifying the print job by adding a tag to each logical page of the job at the control unit;

transmitting the modified print job from the control unit to a printer;

generating target images for the logical pages of the print job at the control unit;

receiving printed pages of the job from the printer at a comparison unit; and

for each printed page;

identifying a tag on the printed page;

identifying a target image corresponding with the tag on the printed page; and

comparing an image of the printed page to the target image to detect discrepancies between the printed page and the target image.

16. The medium of claim 15 wherein modifying the print job comprises:

adding tags that distinguish the printed pages from each other.

17. The medium of claim 15 wherein generating the target images comprises:

generating target images that each comprise a bitmap representing a logical page of the print job.

18. The medium of claim 15 wherein comparing the image of the printed page to the target image comprises:

detecting discrepancies on the printed page where a group of printed pels does not match a group of expected pels defined in the target image.

19. The medium of claim 15 wherein:

the control unit comprises a print server coupled with the printer and the comparison unit.

20. The medium of claim 15 wherein modifying the print job comprises:

adding the tags to a portion of each logical page that will be removed from corresponding printed pages of the print job after printing.