Image tracking apparatus for tracking an image within a local region to continuously track a moving object

• US 6,298,170 B1
• Filed: 01/14/1997
• Issued: 10/02/2001
• Est. Priority Date: 07/23/1996
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Morita, Toshihiko, Sawasaki, Naoyuki
• Primary Examiner(s): Bella, Matthew C.
• Assistant Examiner(s): CHAWAN, SHEELA C
• Application Number:
  US08/783,056
• Time in Patent Office: 1,722 Days
• Field of Search: 382/278, 382/103, 382/104, 382/236, 382/170, 348/169, 345/358
• US Class Current: 382/278
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06T 7/74 involving reference images or patches

Abstract

A local region image tracking apparatus continuously tracks an arbitrary local region within a search image which is described by search image data by comparing the search image data and reference image data related to the arbitrary local region having a size of am pixels by bn pixels with respect to input image data, where the search image has a size larger than am pixels by bn pixels, and a, b, m and n are natural numbers. The local region image tracking apparatus includes correlation computing circuit for computing a correlation between reference image data related to a reference image having a size of m pixels by n pixels and the search image data a plurality of times while moving a position of the reference image with respect to the search image, and for outputting correlation values respectively indicating a computed correlation, and a correlation value accumulating circuit for accumulating the correlation values output from the correlation computing circuit, and for outputting a correlation value indicative of a correlation between the search image data and reference image data related to an equivalent of a reference image having a size of am pixels by bn pixels.

Claims

1. A local region image tracking apparatus for continuously tracking an arbitrary local region within a search image, defined by search image data of a size greater than am by bn pixels, by comparing the search image data of the search image and reference image data, related to the arbitrary local region and of a size of am by bn pixels, where a, b, m and n are natural numbers, a>

1 and b>

1, said local region image tracking apparatus comprising;

correlation computing means for computing a correlation between each of plural sub-reference images comprising respective contiguous portions of a common reference image and defined by respective sub-reference image data, each of a size of m by n pixels, while moving said sub-reference images in individual succession from initial contiguous positions to subsequent contiguous positions thereof with respect to said search image, and for outputting plural correlation values respectively indicating respective, computed correlations between each of the plural, moved sub-reference images and corresponding portions of said search image; and

correlation value accumulating means for accumulating the plural correlation values output from said correlation computing means, and for outputting a correlation value indicative of a correlation between said search image data and reference image data related to an equivalent of a reference image having a size of am by bn pixels.

2. The local region image tracking apparatus as claimed in claim 1, wherein said input image data are input from an input means selected from a group consisting of an image pickup means and an image storage means via a video bus, said correlation computing means and said correlation value accumulating means form a correlation tracking processor, and one or a plurality of correlation tracking processors are coupled in parallel to said input means via said video bus.

3. The local region image tracking apparatus as claimed in claim 2, further comprising:

a control computer controlling said one or plurality of correlation tracking processors,

said one or plurality of correlation tracking processors being coupled in parallel to said control computer via a control bus.

4. The local region image tracking apparatus as claimed in claim 1, said correlation value accumulating means comprising:

a correlation value memory to store a correlation value output from said correlation computing means as a result of a previous correlation computation; and

a correlation value accumulating circuit to obtain an accumulated correlation value by adding a correlation value output from said correlation computing means as a result of a present correlation computation and the correlation value stored in said correlation value memory.

5. The local region image tracking apparatus as claimed in claim 1, said input image data comprising color image data, and said local region image tracking apparatus further comprising:

data conversion means for successively supplying color image data to said correlation computing means with respect to a reference image position and a corresponding search image position, and

said correlation value accumulating means further comprising accumulating correlation values of the color image data with respect to the corresponding reference image position and search image position.

6. The local region image tracking apparatus as claimed in claim 1, further comprising:

a microcomputer unit to control whether to accumulate the correlation values in said correlation value accumulating means, wherein

said correlation computing means, said correlation value accumulating means and said microcomputer unit form a single unit.

7. The local region image tracking apparatus as claimed in claim 1, wherein said input image data are input from an input means selected from a group consisting of an image pickup means and an image storage means, said input image data are displayed on a display means, and said local region image tracking apparatus further comprises:

image input/output means, coupled to the input means and the display means, for receiving said input image data from the input means, wherein

said correlation computing means, said correlation value accumulating means and said image input/output means forming a single unit.

8. The local region image tracking apparatus as claimed in claim 7, further comprising:

a microcomputer unit to control whether to accumulate the correlation values in said correlation value accumulating means, wherein

said correlation computing means, said correlation value accumulating means, said image input/output means and said microcomputer unit forming a single unit.

9. The local region image tracking apparatus as claimed in claim 2, wherein said correlation value accumulating means comprises:

a correlation value memory to store a correlation value output from said correlation computing means as a result of a previous correlation computation; and

a correlation value accumulating circuit to obtain an accumulated correlation value by adding a correlation value output from said correlation computing means as a result of a present correlation computation and the correlation value stored in said correlation value memory.

10. The local region image tracking apparatus as claimed in claim 3, wherein said correlation value accumulating means comprises:

a correlation value memory to store a correlation value output from said correlation computing means as a result of a previous correlation computation; and

a correlation value accumulating circuit to obtain an accumulated correlation value by adding a correlation value output from said correlation computing means as a result of a present correlation computation and the correlation value stored in said correlation value memory.

11. The local region image tracking apparatus as claimed in claim 2, said input image data comprising color image data, and said local region image tracking apparatus further comprising:

data conversion means for successively supplying color image data to said correlation computing means with respect to a reference image position and a corresponding search image position, and

said correlation value accumulating means further comprising accumulating correlation values of the color image data with respect to the corresponding reference image position and search image position.

12. The local region image tracking apparatus as claimed in claim 3, said input image data comprising color image data, and said local region image tracking apparatus further comprising:

data conversion means for successively supplying color image data to said correlation computing means with respect to a reference image position and a corresponding search image position, and

said correlation value accumulating means further comprising accumulating correlation values of the color image data with respect to the corresponding reference image position and search image position.

13. The local region image tracking apparatus as claimed in claim 4, said input image data comprising color image data, and said local region image tracking apparatus further comprising:

data conversion means for successively supplying color image data to said correlation computing means with respect to a reference image position and a corresponding search image position, and

said correlation value accumulating means further comprising accumulating correlation values of the color image data with respect to the corresponding reference image position and search image position.

14. A local region image tracking apparatus for continuously tracking an arbitrary local region within a search image, comprising:

correlation computing means for computing a correlation between reference image data of an m×

n pixel reference image and search image data of said search image while moving portions of said reference image containing respective portions of the reference image data, in succession from respective, initial and contiguously related positions thereof by a common distance and in a common direction, to respective, subsequent and contiguously related positions thereof with respect to said search image, and for outputting correlation values respectively indicating a computed correlation of each moved portion of the reference image data and the corresponding portion of the search image data; and

correlation value accumulating means for accumulating the respective correlation values output from said correlation computing means, and for outputting a correlation value indicative of a correlation between said search image data and said correlated reference image data related to an equivalent of a reference image having a size of am×

bn pixels, wherein a, b, m, and n are natural numbers and a>

1 and b>

1.

15. A local region image tracking apparatus for continuously tracking an arbitrary local region within a search image, comprising:

correlation computing means for computing a correlation between plural reference sub-images, each of an m by n pixel data size, in which sub-images the reference image data is distributed, and respective, corresponding portions of a search image larger than am by bn pixels, wherein a, b, m and n are natural numbers and a>

1 and b>

1, by moving the plural reference sub-images and the respective, corresponding portions of the reference data distributed therein, individually and in succession, from initial contiguously related respective positions to subsequent contiguously related respective positions cumulatively encompassing the entirety of the search image and for outputting correlation values respectively indicating computed correlations at corresponding said initial and subsequent positions; and

correlation value accumulating means for accumulating the correlation values output from said correlation computing means, and for outputting a correlation value indicative of a correlation between said search image data and said reference image data related to an equivalent of a reference image having a size of am by bn pixels.