Image taking and processing device for a digital camera and method for processing image data

• US 6,710,801 B1
• Filed: 03/23/2000
• Issued: 03/23/2004
• Est. Priority Date: 03/29/1999
• Status: Expired due to Fees

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Kubo, Hiroaki
• Primary Examiner(s): HO, TUAN V
• Application Number:
  US09/534,252
• Time in Patent Office: 1,461 Days
• Field of Search: 348/207.99, 348/208.99, 348/208.13, 348/222.1, 348/240.99, 348/240.1, 348/240.3, 348/358, 348/362, 382/300, 382/284, 382/293, 382/294, 382/298, 382/299, 358/428
• US Class Current: 348/222.1
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors
• CPC Class Codes: H04N 23/632 for displaying or modifying preview images prior to image capturing, e.g. variety of image resolutions or capturing parameters
• CPC Class Codes: H04N 23/634 Warning indications
• CPC Class Codes: H04N 23/671 in combination with active ranging signals, e.g. using light or sound signals emitted toward objects
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/843 Demosaicing, e.g. interpolating colour pixel values
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

An image processing technique for improving image resolution by increasing an effective number of pixels that represents a captured image. The technique involves obtaining a first exposure and at least a second exposure of an object. The image data of the second exposure differs from the image data of the first exposure in that a focal length for the second exposure differs from that for the first exposure. To the extent there exists a correlation, the image data of the second exposure is used for pixel data for each pixel of the image data of the first exposure requiring resolution improvement. When such correlation does not exist, pixel interpolation is performed using pixel data created by means of calculation for pixel interpolation positions.

Claims

1. An image taking and processing device for a digital camera, the device comprising:

at least one image sensor, having a fixed number of pixels, to output image signals responsive to an image taking operation;

a selector to select a quantity of pixels to be used in capturing an image, wherein in a first mode of operation the quantity of pixels is greater than the fixed number of pixels;

an image taking lens having zoom functionality;

a controller, responsive to instructions from the selector, to control an image taking operation; and

an image processor, coupled to the at least one image sensor, to process image signals received from the at least one image sensor,

wherein in the first mode of operation, (i) the controller is adapted to change a focal length of the image taking lens subsequent to a first exposure and automatically effect a second exposure of a subject object and (ii) the image processor is adapted to perform pixel interpolation for image data obtained from the first exposure,

wherein the image processor is adapted to determine whether corresponding pixel data from image data obtained from the second exposure exists for pixel interpolation position of image data obtained from the first exposure, and when such pixel data exists, the image processor is adapted to incorporate such pixel data from image data obtained from the second exposure into the image data obtained from the first exposure.

2. A device in accordance with claim 1, wherein the image processor is adapted to calculate pixel data for each pixel interpolation position of the image data obtained from the first exposure and not otherwise replaced by pixel image data of the second exposure.

3. A device in accordance with claim 1, wherein the image processor is adapted to resize an effective image size of the image data obtained from the second exposure in accordance with an effective image size of the image data obtained from the first exposure.

4. A device in accordance with claim 3, wherein the image processor is adapted to calculate pixel data for each pixel interpolation position of the image data obtained from the first exposure and not otherwise replaced by pixel image data of the second exposure.

5. A method for processing image data, comprising the steps of:

obtaining first image data representative of an object;

obtaining second image data representative of the object, wherein the second image data corresponds to a magnification that differs from that of the first image data;

resizing at least one of an effective image size of the first image data and the second image data so as to harmonize the effective image sizes of the first image data and the second image data;

identifying pixel interpolation positions within the first image data;

searching the second image data for pixel data that corresponds to each identified pixel interpolation position; and

replacing each pixel interpolation position of the first image data, which corresponds to specific pixel data of the second image data, with the specific pixel data of the second image data.

6. A method for processing image data in accordance with claim 5, further comprising the step of calculating pixel data for each pixel interpolation position not otherwise subject to replacement.

7. A method for processing image data, comprising the steps of:

receiving first image data representative of an object;

receiving additional image data, the additional image data being representative of the object but comprises image data of a plurality of magnifications that each differ from a magnification of the first image data;

identifying pixel interpolation positions within the first image data;

searching the additional image data for pixel data that corresponds to each identified pixel interpolation position; and

replacing each pixel interpolation position of the first image data, which corresponds to specific pixel data of the additional image data, with the specific pixel data of the additional image data.

8. A method for processing image data in accordance with claim 7, further comprising the step of resizing at least one of an effective image size of the first image data and the additional image data so as to harmonize the respective image sizes of the first image data and the additional image data.

9. A computer readable medium containing a set of computer executable instructions for processing first image data representative of an object and second image data representative of the object, such second image data corresponding to a magnification that differs from that of the first image data, which executable instructions allow a computer to perform the following steps:

resizing at least one of an effective image size of the first image data and the second image data so as to harmonize the effective image sizes of the first image data and the second image data;

identifying pixel interpolation positions within the first image data;

for each identified pixel interpolation position, searching the second image data for specific pixel data that positionally corresponds to such identified pixel interpolation position; and

replacing each pixel interpolation position that corresponds to pixel data of the second image data with positionally corresponding pixel data of the second image data.

10. A computer readable medium containing a set of computer executable instructions for processing image data, which executable instructions allow a computer to perform the following steps:

obtaining first image data representative of an object;

obtaining additional image data, the additional image data being representative of the object but comprises image data of a plurality of magnifications that each differ from a magnification of the first image data;

resizing at least one of an effective image size of the first image data and the additional image data so as to establish a single effective image size for the first image data and the additional image data;

identifying pixel interpolation positions within the first image data;

for each identified pixel interpolation position, searching the additional image data for pixel data that positionally corresponds to such identified pixel interpolation position; and

replacing each pixel interpolation position that positionally corresponds to pixel data of the additional image data by using such pixel data of the additional image data.

11. A method for obtaining and subsequently processing image data for a digital camera having a taking lens with zoom capabilities, the method comprising the steps of:

effecting a first exposure to obtain first image data representative of an object;

modifying a focal length of the taking lens and effecting a second exposure at the modified focal length to obtain second image data representative of the object;

resizing at least one of an effective image size of the first image data and the second image data so as to harmonize an effective image size of the first image data and the second image data;

identifying pixel interpolation positions within the first image data;

searching the second image data for pixel data that corresponds to each identified pixel interpolation position; and

replacing each pixel interpolation position that corresponds to pixel data of the second image data with pixel data of the second image data.

12. A method for processing image data in accordance with claim 11, further comprising the step of calculating pixel data for each pixel interpolation position not otherwise subject to replacement.