Detection of graphics added to a video signal

• US 8,878,999 B2
• Filed: 04/18/2011
• Issued: 11/04/2014
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: Supponor Oy (Supponor Holding Ltd.)
• Original Assignee: Supponor Oy (Supponor Holding Ltd.)
• Inventors: Suontama, Vesa
• Primary Examiner(s): Lee, Michael
• Application Number:
  US14/009,513
• Publication Number:
  US 20140036093A1
• Time in Patent Office: 1,296 Days
• Field of Search: 348/465, 348/468, 382/176, 382/190, 382/182
• US Class Current: 348/600
• CPC Class Codes: G06V 20/40 in video content extracting overlay text G06V20/62; video retrieval G06F16/70; processing of video elementary streams in video servers H04N21/234; processing of video elementary streams in video clients H04N21/44
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details
• CPC Class Codes: H04N 21/23418 involving operations for analysing video streams, e.g. detecting features or characteristics television picture signal circuitry for scene change detection H04N5/147; filtering for image enhancement G06T5/00; methods or arrangements for recognising scenes G06V20/00; arrangements characterised by components specially adapted for monitoring, identification or recognition of video in broadcast systems H04H60/59
• 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 21/8153 comprising still images, e.g. texture, background image
• CPC Class Codes: H04N 5/45 Picture in picture , e.g. displaying simultaneously another television channel in a region of the screen

Abstract

The invention allows detecting which graphics, if any, have been added to the video signal at any given time by utilizing only the various signals provided by prior art hardware. A first video signal, graphics signal(s), and a second video signal are received. It is then determined which graphics, if any, are present in a given frame of the received second video signal based on comparing actual values of pixels of the received second video signal and calculated values of pixels derived from the first video signal, and the graphics signal(s), and the combination of graphics signal(s) which produces the best match is searched for.

Claims

1. A method of detecting the presence of additional graphics in a video signal, the method comprising:

receiving a first video signal, at least one graphics signal, and a second video signal comprising said first video signal mixed at least periodically with the at least one graphics signal;

deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal;

comparing the calculated values with actual values of pixels of a corresponding frame of the received second video signal; and

determining a presence status of the at least one graphics signal in the frame of the received second video signal based on the performed comparison;

wherein receiving a first video signal, at least one graphics signal, and a second video signal comprising said first video signal mixed at least periodically with the at least one graphics signal further comprises receiving transparency information indicating transparency of at least a portion of a frame of an associated graphics signal, and said deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal further comprises deriving the calculated values from the received transparency information in addition to the frame of the received first video signal and the corresponding frame of the received at least one graphics signal.

2. The method according to claim 1, wherein deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal further comprises deriving the calculated values for a number of presence combinations of the at least one graphics signal.

3. The method according to claim 2, wherein determining a presence status of the at least one graphics signal in the frame of the received second video signal based on the performed comparison is performed by selecting the presence combination the calculated values of which best match with the compared actual values according to a statistical criterion, as indicative of said presence status of the at least one graphics signal in the frame of the received second video signal.

4. The method according to claim 1, further comprising producing an effective result of at least one of used graphics information and associated resulting transparency information, based on said determined presence status.

5. The method according to claim 4, further comprising applying the produced used graphics information and its associated used transparency information to one or more additional incoming video signals to produce one or more additional output video signals.

6. An apparatus for detecting the presence of additional graphics in a video signal, the apparatus comprising:

a receiver configured to receive a first video signal, at least one graphics signal, and a second video signal comprising said first video signal mixed at least periodically with the at least one graphics signal;

a calculator configured to derive calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal;

a comparator configured to compare the calculated values with actual values of pixels of a corresponding frame of the received second video signal; and

a selector configured to determine a presence status of the at least one graphics signal in the frame of the received second video signal based on the performed comparison;

wherein the receiver is further configured to receive transparency information indicating transparency of at least a portion of a frame of an associated graphics signal, and said calculator is further configured to derive the calculated values from the received transparency information in addition to the frame of the received first video signal and the corresponding frame of the received at least one graphics signal.

7. The apparatus according to claim 6, wherein the calculator is further configured to derive the calculated values for a number of presence combinations of the at least one graphics signal.

8. The apparatus according to claim 7, wherein the selector is configured to perform said determination of said presence status by selecting the presence combination the calculated values of which best match with the compared actual values according to a statistical criterion, as indicative of said presence status of the at least one graphics signal in the frame of the received second video signal.

9. The apparatus according to claim 6, further comprising an information producer configured to produce an effective result of at least one of used graphics information and associated resulting transparency information, based on said determined presence status.

10. The apparatus according to claim 9, further comprising an information applying unit configured to apply the produced used graphics information and its associated used transparency information to one or more additional incoming video signals to produce one or more additional output video signals.

11. A computer program product stored in a non-transitory computer readable medium for detecting additional graphics in a video signal, the computer program product comprising software instructions which, when run, causes a data-processing system to perform the following:

receiving a first video signal, at least one graphics signal, and a second video signal comprising said first video signal mixed at least periodically with the at least one graphics signal;

deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal;

comparing the calculated values with actual values of pixels of a corresponding frame of the received second video signal; and

determining a presence status of the at least one graphics signal in the frame of the received second video signal based on the performed comparison;

wherein said receiving a first video signal, at least one graphics signal, and a second video signal comprising said first video signal mixed at least periodically with the at least one graphics signal further comprises receiving transparency information indicating transparency of at least a portion of a frame of an associated graphics signal, and said deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal further comprises deriving the calculated values from the received transparency information in addition to the frame of the received first video signal and the corresponding frame of the received at least one graphics signal.

12. The computer program product according to claim 11, wherein said deriving calculated values of pixels from a frame of the received first video signal and a corresponding frame of the received at least one graphics signal further comprises deriving the calculated values for a number of presence combinations of the at least one graphics signal.

13. The computer program product according to claim 12, wherein said determining a presence status of the at least one graphics signal in the frame of the received second video signal based on the performed comparison is performed by selecting the presence combination the calculated values of which best match with the compared actual values according to a statistical criterion, as indicative of said presence status of the at least one graphics signal in the frame of the received second video signal.

14. The computer program product according to claim 11, wherein the computer program product further causes the data-processing system to produce an effective result of at least one of used graphics information and associated resulting transparency information, based on said determined presence status.

15. The computer program product according to claim 14, wherein the computer program product further causes the data-processing system to apply the produced used graphics information and its associated used transparency information to one or more additional incoming video signals to produce one or more additional output video signals.