Region of Interest Tracking and Integration Into a Video Codec

• US 20110228846A1
• Filed: 09/20/2010
• Published: 09/22/2011
• Est. Priority Date: 08/26/2005
• Status: Abandoned Application

• Current Assignee: Rafael Realty Holdings, Inc. (IDT Corporation)
• Original Assignee: Rafael Realty Holdings, Inc. (IDT Corporation)
• Inventors: Kutliroff, Gershom, Eshar, Dagan, Eilat, Eran, Yagur, Shai Shimon
• Application Number:
  US12/886,206
• Publication Number:
  US 20110228846A1
• Time in Patent Office: Days
• US Class Current: 375/240.08
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: H04N 19/17 the unit being an image region, e.g. an object
• CPC Class Codes: H04N 19/20 using video object coding

Abstract

There is provided a system for tracking a region of interest in a video includes an identifier for identifying the region of interest and determining a location of the region of interest in a first frame of a video sequence, and a tracker for locating the region of interest in at least a second frame, based on a location of the region of interest in the first frame. The system also includes a recovery manager for determining whether the tracker has correctly located the region of interest. There is also provided a method for tracking a region of interest in a video.

Claims

1. A system for tracking a region of interest in a video, comprising:

an identifier for identifying said region of interest and determining a location of said region of interest in a first frame of a video sequence;

a tracker for locating said region of interest in at least a second frame, based on a location of said region of interest in said first frame;

a recovery manager for determining whether said tracker has correctly located said region of interest;

a calculator that calculates a first quantization level for said region of interest, and calculates a second quantization level for a second region of an image in said video sequence; and

a compressor that produces a compressed bitstream having said first level of quantization for said region of interest, and said second level of quantization for said second region.

2. The system of claim 1, wherein said recovery manager determines whether said tracker has correctly located said region of interest by comparing characteristics of a region located by said tracker in said second frame to pre-selected characteristics of said region of interest identified in said first frame, and wherein said recovery manager re-applies said identifier to said second frame if said characteristics do not match said pre-selected characteristics within a selected tolerance.

3. The system of claim 1, wherein said region of interest is one or more faces.

4. The system of claim 1, wherein said region of interest is a plurality of independent regions of interest.

5. The system of claim 1, wherein said recovery manager determines when to apply said identifier and said tracker by comparing a region located by said tracker in a selected frame by comparing characteristics of a region located by said tracker in said second frame to pre-selected characteristics of said region of interest identified in said first frame.

6. The system of claim 5, wherein said recovery manager directs said system to re-apply said identifier to said selected frame if said characteristics do not match said pre-selected characteristics within a selected tolerance.

7. The system of claim 1, wherein said identifier calculates a color probability distribution that takes into account the probability of a pixel having the same color as a color found in said region of interest.

8. The system of claim 7, wherein said color probability distribution is a probability density function that represents the probability that a color appears in the region of interest.

9. The system of claim 7, wherein said tracker determines a location of said region of interest based on said color probability distribution.

10. The system of claim 1, wherein said calculator calculates said first and second levels of quantization so that said compressed bitstream has a bitrate of less than a target value.

16. The system of claim 1, wherein said second quantization level is based on a location of said second region relative to a location of said region of interest.

11. A method for tracking a region of interest in a video, comprising:

identifying said region of interest and determining a location of said region of interest in a first frame of a video sequence;

attempting to locate said region of interest in at least a second frame, based on a location of said region of interest in said first frame;

determining whether said attempting has correctly located said region of interest, and if so, then;

dividing said image into a plurality of macroblocks;

determining whether each macroblock of said plurality of macroblocks falls in at least a portion of said region of interest; and

compressing each said macroblock into a bitstream having a size depending on a desired video quality of uncompressed video of said macroblock, wherein each said macroblock has a video quality based on whether said macroblock falls in said portion.

12. The method of claim 11, wherein said step of determining includes periodically comparing selected characteristics of said region of interest with pre-selected characteristics to determine whether said attempting is correctly tracking said first region.

13. The method of claim 12, further comprising repeating the steps of identifying and locating said region of interest if said characteristics do not match said pre-selected characteristics within a selected tolerance.

14. The method of claim 11, wherein said region of interest is an image of one or more faces.

15. The method of claim 11, wherein said video quality is highest for said macroblock falling entirely in said region of interest, and said video quality is lowest for said macroblock falling entirely in a region other than said region of interest.