METHODS AND APPARATUS TO DETECT A BLANK FRAME IN A DIGITAL VIDEO BROADCAST SIGNAL

• US 20070083883A1
• Filed: 09/25/2006
• Published: 04/12/2007
• Est. Priority Date: 03/29/2004
• Status: Active Grant

• Current Assignee: The Nielsen Company LLC (MOOD Media Corporation)
• Original Assignee: The Nielsen Company LLC (MOOD Media Corporation)
• Inventors: Deng, Kevin
• Granted Patent: US 7,984,462 B2
• Time in Patent Office: Days
• US Class Current: 725/19
• CPC Class Codes: G01R 19/0015 separating AC and DC
• CPC Class Codes: G11B 27/28 by using information signals recorded by the same method as the main recording G11B27/22 takes precedence
• CPC Class Codes: H04H 60/32 Arrangements for monitoring conditions of receiving stations, e.g. malfunction or breakdown of receiving stations
• CPC Class Codes: H04H 60/37 for identifying segments of broadcast information, e.g. scenes or extracting programme ID
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 21/25866 Management of end-user data customer care in data networks H04L41/5077
• CPC Class Codes: H04N 21/44008 involving operations for analysing video streams, e.g. detecting features or characteristics in the video stream arrangements characterised by components specially adapted for monitoring, identification or recognition of video in broadcast systems H04H60/59
• CPC Class Codes: H04N 21/6582 Data stored in the client, e.g. viewing habits, hardware capabilities, credit card number arrangements where receivers interact with the broadcast H04H20/38
• CPC Class Codes: H04N 21/812 involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 5/45 Picture in picture , e.g. displaying simultaneously another television channel in a region of the screen
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence

Abstract

Methods and apparatus to detect blank images in a digital video broadcast signal are disclosed. An example method of detecting a blank image includes analyzing DC values of luminance blocks associated with a frame to determine a number of the luminance blocks having substantially the same DC value; and identifying the frame as a blank image if the number exceeds a predetermined threshold.

Claims

1. A method of detecting a blank image comprising:

analyzing a compressed frame of a tuned digital broadcast signal to determine if the frame is a blank candidate; and

analyzing a portion of the blank candidate to determine if the blank candidate is a blank image.

2. A method as defined in claim 1 wherein analyzing a compressed frame of the tuned digital broadcast signal to determine if the frame is a blank candidate comprises comparing a bit allocation of substantially the entire compressed frame to a threshold.

3. A method as defined in claim 2 wherein analyzing a compressed frame of the tuned digital broadcast signal to determine if the frame is a blank candidate comprises analyzing a distribution of bits in predetermined areas of the frame.

4. A method as defined in claim 1 wherein analyzing a compressed frame of the tuned digital broadcast signal to determine if the frame is a blank candidate comprises analyzing a distribution of bits in predetermined areas of the frame.

5. A method as defined in claim 4 wherein each of the predetermined areas has substantially the same size.

6. A method as defined in claim 4 wherein the predetermined areas comprise rows of the frame.

7. A method as defined in claim 1 wherein analyzing a compressed frame of the tuned digital broadcast signal to determine if the frame is a blank candidate comprises analyzing bit allocations of rows of the compressed frame.

9. A method as defined in claim 1 wherein analyzing a portion of the blank candidate to determine if the blank candidate is a blank image comprises analyzing one area of the blank candidate.

10. A method as defined in claim 9 wherein the analyzed area comprises one slice of the blank candidate.

11. A method as defined in claim 1 wherein analyzing a portion of the blank candidate to determine if the blank candidate is a blank image comprises analyzing an area of the blank candidate to determine if the area is a blank area.

12. A method as defined in claim 11 wherein the analyzed area of the blank candidate comprises a slice of the blank candidate.

13. A method as defined in claim 11 wherein determining if the area is a blank area comprises determining a number of DC values in the area having a predetermined characteristic.

14. A method as defined in claim 11 wherein determining if the area is a blank area comprises determining if more than a predetermined number of codes representing zero change in brightness are located in the area.

15. A method as defined in claim 11 wherein determining if the area is a blank area comprises determining if a predetermined region of a histogram reflecting DC values in the area contains more than a predetermined percentage of the DC values in the area.

8. A method as defined in claim 8 wherein analyzing the bit allocations of the rows of the frame comprises determining if at least a predetermined percentage of the rows are allocated less than a predetermined number of bits.

16. An apparatus to detect a blank image comprising:

a blank frame candidate identifier to analyze a compressed frame of a tuned digital broadcast signal to determine if the frame is a blank candidate; and

a blank frame tester to analyze a portion of the blank candidate to determine if the blank candidate is a blank image.

17. An apparatus as defined in claim 16 wherein the blank frame candidate identifier determines if the frame is a blank candidate by comparing a bit allocation of substantially the entire compressed frame to a threshold.

18. An apparatus as defined in claim 17 wherein the blank frame candidate identifier determines if the frame is a blank candidate by analyzing a distribution of bits in predetermined areas of the frame.

19. An apparatus as defined in claim 16 wherein the blank frame candidate identifier determines if the frame is a blank candidate by analyzing a distribution of bits in predetermined areas of the frame.

20. An apparatus as defined in claim 19 wherein each of the predetermined areas has substantially the same size.

21. An apparatus as defined in claim 19 wherein the predetermined areas comprise rows of the frame.

22. An apparatus as defined in claim 16 wherein the blank frame candidate identifier determines if the frame is a blank candidate by analyzing bit allocations of rows of the frame.

23. An apparatus as defined in claim 22 wherein the blank frame candidate identifier analyzes the bit allocations of the rows of the frame by determining if at least a predetermined percentage of the rows are allocated less than a predetermined number of bits.

24. An apparatus as defined in claim 16 wherein the blank image tester determines if the blank candidate is a blank image by analyzing an area of the blank candidate.

25. An apparatus as defined in claim 16 wherein the blank image tester determines if the blank candidate is a blank image by analyzing a slice of the blank candidate to determine if the slice is a blank slice.

26. An apparatus as defined in claim 25 wherein the blank image tester determines if the slice is a blank slice by determining a number of DC values in the slice having a predetermined characteristic.

27. A method of detecting a blank image comprising:

receiving a compressed digital image including a plurality of DC values;

determining a number of DC values in the plurality of DC values that meet a predetermined criterion;

comparing the determined number of DC values meeting the predetermined criterion to a predetermined threshold; and

identifying the received digital image as a blank image if the determined number of DC values exceeds the predetermined threshold.

28. A method as defined in claim 27 wherein determining the number of DC values meeting the predetermined criterion comprises, for each DC value except for the first DC value in the plurality, determining if a difference between the DC value and a previous DC value is substantially zero.

29. A method as defined in claim 27 wherein the plurality of DC values are contained within a same slice of a frame.

30. A method as defined in claim 27 wherein determining the number of DC values meeting the predetermined criterion is performed without decompressing the compressed digital image.

31. A method as defined in claim 27 wherein determining the number of DC values meeting the predetermined criterion comprises determining a number of relative DC values in the plurality of DC values that are substantially equal to zero.

32. A method as defined in claim 27 wherein determining the number of DC values meeting the predetermined criterion comprises determining a number of relative DC values in the plurality of DC values that are less than a predetermined threshold.

33-86. -86. (canceled)