System and method for displaying an image indicating a positional relation between partially overlapping images

• US 6,466,701 B1
• Filed: 09/09/1998
• Issued: 10/15/2002
• Est. Priority Date: 09/10/1997
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Aoki, Shin, Saitoh, Takashi, Haike, Guan, Sakamoto, Takuji, Ejiri, Koichi
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): Kassa, Yosef
• Application Number:
  US09/150,288
• Time in Patent Office: 1,497 Days
• Field of Search: 382/284, 382/318, 382/131, 382/282, 382/287, 382/291, 382/293, 382/294, 345/115, 345/345, 348/584, 348/601, 348/588, 348/222, 348/231, 348/239, 348/49, 348/50, 348/53, 348/56
• US Class Current: 382/284
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2200/32 involving image mosaicing
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20021 Dividing image into blocks, subimages or windows
• CPC Class Codes: G06T 7/223 using block-matching
• CPC Class Codes: G06T 7/30 Determination of transform parameters for the alignment of images, i.e. image registration
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence

Abstract

A camera system includes a display monitor which displays an image of an object, taken by an optical unit, on a screen of the monitor. A reading unit reads a preceding image and a current image among a plurality of partially overlapping images, from a memory device, the preceding image and the current image containing a common element. A determining unit determines a positional relation between the preceding image and the current image based on a common pattern derived from the common element in the two adjacent images read by the reading unit. A displaying unit displays an image indicating a boundary of the preceding image on the screen of the monitor at a shifted position according to the positional relation determined by the determining unit, with the current image concurrently displayed on the screen of the monitor.

Claims

1. A camera system comprising:

a display monitor for displaying an image of an object, taken by an optical unit and stored in a frame buffer, on a screen of the monitor;

a reading unit for reading a preceding image and a current image among a plurality of partially overlapping images, from the frame buffer, the preceding image and the current image containing a common element;

a determining unit for determining a positional relation between the preceding image and the current image based on a common pattern derived from the common element in the two adjacent images read by the reading unit; and

a displaying unit for displaying, when a shutter switch is turned on, a displaying unit image comprising the concurrent display of (i) a boundary image indicating a boundary of the preceding image on the screen of the monitor at a shifted position according to the positional relation determined by the determining unit, and (ii) the current image, wherein one of the plurality of partially overlapping images is defined by the overlap of the boundary image and the current image.

2. The camera system according to claim 1, wherein the determining unit performs a matching between corresponding blocks taken from an overlapping portion of the two adjacent images, so that a maximum-similarity common pattern in the two adjacent images is identified.

3. The camera system according to claim 1, wherein the determining unit performs a matching between corresponding blocks taken from an overlapping portion of the two adjacent images by checking intensities of individual pixels of the corresponding blocks.

4. The camera system according to claim 1, wherein the determining unit determines both coordinates of a central pixel of a maximum-similarity common pattern in the preceding image and coordinates of a central pixel of the maximum-similarity common pattern in the current image.

5. The camera system according to claim 1, further comprising:

a sensor for outputting an optical axis direction signal indicating a direction of an optical axis of the optical unit; and

a secondary determining unit for determining a positional relation between the preceding image and the current image based on a difference between the optical axis direction signal output by the sensor with respect to the current image and the optical axis direction signal output by the sensor with respect to the preceding image.

6. The camera system according to claim 1, wherein the determining unit determines a displacement vector, indicating a positional relation between the preceding image and the current image, based on a difference between coordinates of a central pixel of a maximum-similarity common pattern in the preceding image and coordinates of a central pixel of the maximum-similarity common pattern in the current image, and wherein the displaying unit displays an image of the displacement vector on the screen of the monitor with the current image concurrently displayed on the screen of the monitor.

7. The camera system according to claim 1, further comprising an image storing unit for storing an image of the object, taken by the optical unit, in an image memory, wherein the image storing unit stores auxiliary data, containing information indicating the positional relation from the determining unit, in the image memory, in addition to the image stored therein.

8. The camera system according to claim 5, further comprising an image storing unit for storing an image of the object, taken by the optical unit, in an image memory, wherein the image storing unit stores auxiliary data, containing information indicating the positional relation from the secondary determining unit, in the image memory, in additional to the image stored therein.

17. The camera system according to claim 1, wherein the displaying unit displays a displacement vector, corresponding to the positional relation between the preceding image and the current image, during movement of an optical axis of the optical unit.

9. A divisional shooting method for a camera system in which at least two of partially overlapping images of an object, taken by an optical unit and stored in a frame buffer, are displayed, comprising the steps of:

reading a preceding image and a current image among the partially overlapping images, from the frame buffer, the preceding image and the current image containing a common element;

determining a positional relation between the preceding image and the current image based on a common pattern derived from the common element in the two adjacent images; and

displaying, when a shutter switch is turned on, a displaying unit image comprising the concurrent display of (i) a boundary image indicating a boundary of the preceding image on a screen of a display monitor at a shifted position according to the positional relation determined by the determining step, and (ii) the current image, wherein one of the at least two partially overlapping images is defined by the overlap of the boundary image and the current image.

10. The method according to claim 9, wherein, in the determining step, a matching between corresponding blocks taken from an overlapping portion of the two adjacent images is performed, so that a maximum-similarity common pattern in the two adjacent images is identified.

11. The method according to claim 9, wherein, in the determining step, a matching between corresponding blocks taken from an overlapping portion of the two adjacent images is performed by checking intensities of individual pixels of the corresponding blocks.

12. The method according to claim 9, wherein, in the determining step, both coordinates of a central pixel of a maximum-similarity common pattern in the preceding image and coordinates of a central pixel of the maximum-similarity common pattern in the current image are determined.

13. The method according to claim 9, further comprising the steps:

outputting an optical axis direction signal indicating a direction of an optical axis of the optical unit; and

determining a positional relation between the preceding image and the current image based on a difference between the optical axis direction signal output by the sensor with respect to the current image and the optical axis direction signal output by the sensor with respect to the preceding image.

14. The method according to claim 9, wherein, in the determining step, a displacement vector, indicating a positional relation between the preceding image and the current image, is determined based on a difference between coordinates of a central pixel of a maximum-similarity common pattern in the preceding image and coordinates of a central pixel of the maximum-similarity common pattern in the current image, and wherein, in the displaying step, an image of the displacement vector is displayed on the screen of the monitor with the current image concurrently displayed on the screen of the monitor.

15. The method according to claim 9, further comprising a step of storing an image of the object, taken by the optical unit, in an image memory, wherein auxiliary data, containing information indicating the positional relation from the determining unit, is stored in the image memory in addition to the image stored therein.

16. The method according to claim 13, further comprising a step of storing an image of the object, taken by the optical unit, in an image memory, wherein auxiliary data, containing information indicating the positional relation from the secondary determining unit, is stored in the image memory, in additional to the image stored therein.

18. The method according to claim 9, further comprising the step of displaying a displacement vector, corresponding to the positional relation between the preceding image and the current image, during movement of an optical axis of the optical unit.