Digital wide camera

• US 6,466,262 B1
• Filed: 06/09/1998
• Issued: 10/15/2002
• Est. Priority Date: 06/11/1997
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ejiri, Masakazu, Miyatake, Takafumi, Nagasaka, Akio
• Primary Examiner(s): Garber, Wendy R.
• Assistant Examiner(s): VILLECCO, JOHN M
• Application Number:
  US09/093,782
• Time in Patent Office: 1,589 Days
• Field of Search: 348/36, 348/218, 348/699, 382/206, 382/284, 382/194
• US Class Current: 382/284
• CPC Class Codes: H04N 1/0044 for image preview or review, e.g. to help the user position a sheet
• CPC Class Codes: H04N 1/2112 using still video cameras
• CPC Class Codes: H04N 1/2133 Recording or reproducing at a specific moment, e.g. time interval or time-lapse
• CPC Class Codes: H04N 1/215 Recording a sequence of still pictures, e.g. burst mode
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/14 Picture signal circuitry for video frequency region cameras or camera modules comprising electronic image sensors, or control thereof H04N23/00
• CPC Class Codes: H04N 5/77 between a recording apparatus and a television camera
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/781 on disks or drums
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

A digital wide camera is capable of forming, in real time, a wide view still image from a dynamic sequence of images generated during a recording operation by panning the camera to capture a scene. The camera shoots each frame of the sequence with a certain angular field of view at 30 frames per second, for example. The wide view still image has an apparent field of angular view that is greater than that of the image of each frame. The images of the sequence are connected together by determining a shift in position between adjacent images and then overwriting each image to a wide view image buffer after shifting the image by the shift amount. Determining the shift amounts and overwriting the image buffer is accomplished in less time than the interval between shooting consecutive images so that the display of the wide view image can be updated in real time for a user'"'"'s observation. The amount of shift in position is determined using global pattern matching between adjacent images by taking the projections of the intensity values of the pixels in the horizontal and vertical directions of the images being compared. The projections are subjected to collation processing to identify the amounts in shift in each direction.

Claims

1. A digital camera, comprising:

an operation input means for starting and ending recording of a scene;

an image sensing device for capturing a plurality of images of a scene as a dynamic image;

a shift value determining means for determining amounts of shift in position between consecutive ones of the plurality of images due to movement of the camera during the recording;

and a wide view image display means for displaying a wide view image obtained by connecting the consecutive images by overwriting a current one of said consecutive images with respect to a last one of said consecutive images by the amount of shift in position determined by said shift value determining means, wherein;

said shift determining means uses global pattern matching between the consecutive images taking the projections of the intensity values of the pixels in the horizontal and vertical directions, and

said wide view image display means sequentially displays wide view image that is formed from the start to the end of the recording.

2. A digital camera according to claim 1, further comprising:

image storage means for storing said wide view image and said dynamic image, wherein said plurality of images of said dynamic image are read out from said image storage means, and said wide view image is displayed on said wide view image display means as said plurality of images are read out.

3. A digital camera according to claim 1, wherein said shift value determining means includes a pixel intensity value projection distribution determining and storage means for storing distributions of projections in pixel intensity in the horizontal and vertical directions of the current and last images, and a projection distribution collating means for detecting, by collation, the amounts of shift in position among the projection distributions in the horizontal and vertical same directions for the current and last images, wherein the amounts of shift in position of the projection distributions in the horizontal and vertical directions are used as the amounts of shift in position among the consecutive images due to the movement of the camera.

4. A digital camera according to claim 3, wherein said pixel intensity value projection distribution determining and storing means determines said projection distributions by normalizing the results of integration of the intensity values of pixels constituting an image in the horizontal direction and the vertical direction, respectively, with respect to the number of pixels in the integration.

5. A digital camera according to claim 3, wherein the projection distribution in said projection distribution storage means is displayed on said wide image display means as a two-dimensional time-space image, one dimension being such that the individual values are used as densities of image, and another dimension being the time axis of the recording section.

6. A digital camera according to claim 5, wherein said time-space images are successively displayed on said wide image display means from the start to the end of the recording.

7. A digital camera according to claim 3, wherein said wide view image display means scales down said wide view image for displaying said wide view image.

8. A digital camera according to claim 3, wherein said projection distribution collating means includes a partial coincidence detecting means for detecting a section in which the two projection distributions to be collated are partially coincident, a voting means for adding the corresponding elements of a voting array based on the amount of relative shift in position in the partially coincident section, and a maximum value detecting means for detecting a maximum value of the content of the voting array formed by said voting means, wherein the amount of shift in position is determined from the element number in the voting array which is the maximum value.

9. A digital camera according to claim 8, wherein said partial coincidence detecting means detects coincident sections for all partial sections in the projection distributions being collated.

10. A digital camera according to claim 8, wherein in said partial coincidence detecting means, a criterion for judging coincidence is set so that the absolute value of the difference between the two projection distributions to be collated is smaller than a predetermined value.

11. A digital camera according to claim 8, wherein said partial coincidence detecting means includes a matched list means for searching for elements having values that are in agreement between the two projection distributions being collated and for initializing the mutual element numbers and the lengths of coincident sections of the structures to 1, and a positional shift detecting means for referring to the structures that are listed, judging whether the elements of the projection distributions are coincident, updating the length of the coincident section of the corresponding structures when there is coincidence, finding the amount of relative shift in position from the difference in the mutual element numbers between the structures when there is not coincidence, and erasing the structures.

12. A digital camera according to claim 11, wherein said matched list means performs the list in the range such that the absolute value of the difference in the element numbers between the projection distributions does not exceed a predetermined range.

13. A digital camera according to claim 8, wherein when the maximum value is smaller than a predetermined value, it is so regarded that the detection of the amount of shift in position has failed, and an amount of the shift in position is set to 0.

14. A program resides in a memory which executes;

a step of determining amounts of shift in position between consecutive ones of the plurality of images captured by an image sensing device by using global pattern matching between the consecutive images by taking the projections of the intensity values of the pixels in the horizontal and vertical directions;

a step of obtaining a wide view image by connecting the consecutive images by the amount of shift in position determined in said shift determining step;

a step of displaying a wide view image on a display.