Video camera having a vibrating image-processing operation

• US 5,307,170 A
• Filed: 10/29/1991
• Issued: 04/26/1994
• Est. Priority Date: 10/29/1990
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Itsumi, Kazuhiro, Watanabe, Mutsumi, Izumi, Mamoru
• Primary Examiner(s): Mancuso, Joseph
• Assistant Examiner(s): Ho, Tuan V.
• Application Number:
  US07/784,586
• Time in Patent Office: 910 Days
• Field of Search: 358/209, 358/227, 358/228, 358/41, 358/51, 358/55, 354/430, 354/401, 354/402, 354/403, 354/404, 354/400
• US Class Current: 348/219.1
• 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 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 23/676 Bracketing for image capture at varying focusing conditions
• CPC Class Codes: H04N 23/743 Bracketing, i.e. taking a series of images with varying exposure conditions
• CPC Class Codes: H04N 25/48 Increasing resolution by shifting the sensor relative to the scene

Abstract

A video camera includes a vibration generation section including a camera body having a lens system with an auto-focus mechanism, an image pickup element, arranged along an optical axis of the camera body, for picking up an optical image obtained through the lens system, and a piezoelectric actuator for linearly vibrating the image pickup element with a predetermined amplitude at a predetermined period along the direction of the optical axis, an image signal processing circuit for A/D-converting a plurality of images time-serially obtained at arbitrary positions within the amplitude of the image pickup element vibrating along the optical axis, and an image memory for storing the plurality of time-serial images, further including an image input processing section consisting of an in-focus decision/extraction circuit for selecting and extracting clear in-focus areas of a predetermined image area, and an image synthesizing circuit for selecting desired ones of the plurality of areas from the image memory and synthesizing the selected areas into one image. The video camera of this invention further includes an intrusion decision function wherein a time-serial image having small positional and time differences is used within picked image coordinates, an optical flow between these features areas is obtained, and intrusion is decided by using the FOE point from which motion vectors of a stationary object are generated from a motion vector string obtained from the corresponding area in this optical flow.

Claims

1. A video camera comprising:

an image pickup element for receiving optical information of an object to be photographed after the optical information passes through a lens system, and performing an image pickup operation;

vibration generating means, coupled to said image pickup element, for applying a vibration to said image pickup element with a predetermined stroke (amplitude) in the direction of the optical axis;

sampling means for extracting image signals at predetermined time intervals from a plurality of image signals of different focal positions obtained from said image pickup element at a plurality of arbitrary positions within the stroke;

image memory means for time-serially storing sampling images acquired from said image pickup element; and

in-focus decision extracting means for extracting a high-frequency component from an image signal of the sampling image, detecting a focal point evaluation value for evaluating a degree of focusing upon integrating processing, comparing the focal point evaluation values of the plurality of images, and selecting a sampling image having a largest focusing precision value.

2. A video camera comprising:

an image pickup element for receiving optical information of an object to be photographed after the optical information passes through a lens system, and performing an image pickup operation;

vibration generating means, coupled to said image pickup element, for applying a vibration to said image pickup element with a predetermined stroke (amplitude) in the direction of the optical axis;

sampling means for extracting image signals at predetermined time intervals from a plurality of image signals of different focal positions obtained from said image pickup element at a plurality of arbitrary positions within the stroke;

image memory means for time-serially storing sampling images acquired from said image pickup element;

in-focus decision extracting means for extracting a high-frequency component from an image signal of the sampling image, detecting a focal point evaluation value for evaluating a degree of focusing upon integrating processing, comparing the focal point evaluation values of the plurality of images, and selecting a sampling image having a largest focusing precision value; and

image synthesizing means for dividing the sampling image into a plurality of areas as needed, performing focus detection in each divided area, and extracting only in-focus areas from said image memory means to synthesize the in-focus areas into a single image.

3. A video camera comprising:

an image pickup element for receiving optical information of an object to be photographed after the optical information passes through a lens system, and performing an image pickup operation;

vibration generating means, coupled to said image pickup element, for applying a vibration to said image pickup element with a predetermined stroke (amplitude) in the direction of the optical axis, wherein said vibration generating means comprises;

a vibration drive source, coupled to said lens system or said image pickup element, for applying a vibration drive force to one of said lens system and said image pickup element, and

vibration source control means for applying a predetermined control signal to said vibration drive source to generate a vibration at a predetermined period;

sampling means for extracting image signals at predetermined time intervals rom a plurality of image signals of different focal positions obtained from said image pickup element at a plurality of arbitrary positions within the stroke;

image memory means for time-serially storing sampling images acquired from said image pickup element; and

in-focus decision extracting means for extracting a high-frequency component from an image signal of the sampling image, detecting a focal point evaluation value for evaluating a degree of focusing upon integrating processing, comparing the focal point evaluation values of the plurality of images, and selecting a sampling image having a largest focusing precision value.

4. A video camera according to claim 5, wherein said vibration source control means comprises an actuator control circuit;

and

said vibration drive source comprises a piezoelectric actuator,

said piezoelectric actuator being constituted by two cantilevered bimorph structures each comprising a plurality of S-shaped driven bimorph elements.