Video camera having focusing and image-processing function

Claim 2

A video camera comprising: an image pickup element (20) 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 (100), mechanically coupled to said image pickup element, for applying a vibration to said image pickup element with a predetermined stroke of amplitude in the direction of the optical axis; sampling means (22) 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 positions within the stroke; and image memory means (35) for time-serially storing sampling images acquired from said image pickup element; characterised in that said vibration generating means (100) has a vibration drive source (70) comprising a piezoelectric actuator, said piezoelectric actuator being constituted by two cantilevered bimorph structures each consisting of a plurality of S-shaped driven bimorph elements (71a-71f).

Claim 3

A video camera according to claim 2, characterised by further comprising: in-focus decision extracting means (24) 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.

Claim 4

A video camera according to claim 2, characterized by further comprising: image synthesizing means (26) for dividing the sampling image into a plurality of areas 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.

Claim 5

A video camera according to claim 2, characterised by including: said lens system (10) for focusing optical information of an object to be photographed or the like; said image pickup element (20) for performing electrical image pickup operations; said vibration generating means (100) for vibrating said image pickup element itself, or part or all of said lens system with a predetermined amplitude at a predetermined period in a direction of an optical axis; an image input system (200), connected to said vibration generating means, for performing predetermined information conversion processing for processing an image output; and said image memory (35) for storing the image output; further including a CPU (90) for controlling the image processing, a control bus (9) connected to said CPU to transmit a control signal from said CPU, and an image bus (8) for transmitting image information, wherein said control bus is connected to: an optical flow detecting system (300) for detecting features and similarity points of the image; an optical flow memory (65) for storing information associated with the optical flow for surveillance processing; a Focus of Expansion, abbreviated FOE, measuring circuit system (400) for measuring an FOE point from which the optical flow of a stationary object in the image is generated; and an intrusion decision circuit system (500) for detecting an intrusion object.

Claim 6

A video camera according to claim 5, characterised in that: said image input system (200) performs predetermined conversion processing of input image information obtained in a half cycle of a vibration period and stores processed information in said image memory through said image bus, and said image input system (200) comprises: an A/D converter (6) for converting the image signal output from said camera body (1) into a digital signal; and an ITV interface (7) for transmitting the digital image signal to said image memory (35).

Claim 7

A video camera according to claim 5, characterized in that: said optical flow detecting system (300) obtains a motion associated with a corresponding area from a plurality of time-serial images prestored in said image memory in accordance with predetermined analysis processing to obtain an optical flow of the corresponding area, and said optical flow detecting system (300) comprises: a feature and similarity detector circuit (310) for detecting features and similarity points of the images; and a feature and similarity detection memory (350) for storing the detection process and a detection result thereof.

Claim 8

A video camera according to claim 5, characterised in that: said FOE measuring circuit system (400) analyzes motions of a background and an object to obtain an optical flow between images of the background and the object, and measures an FOE (Focus of Expansion) point in which an optical flow of a stationary object obtained upon movement of an image pickup plane in a direction of an optical axis is generated from a motion vector string obtained by connecting corresponding vectors of the optical flow, and said FOE measuring circuit system (400) comprises: a line detecting circuit (42) for obtaining linear expressions from the motion vector string based on the optical flow by using a predetermined method; an FOE calculation circuit (44) for obtaining intersections of a plurality of straight lines represented by the linear expressions and calculating coordinates of the FOE point according to a predetermined method; and an FOE memory (46) for storing the calculated coordinates of the FOE point.

Claim 9

A video camera according to claim 5, characterised in that: said intrusion decision circuit system (500) decides to separate the plurality of images into an image having the FOE point and an image having no FOE point to detect an intrusion object, and said intrusion decision circuit system (500) comprises: a decision circuit (52) for determining that the lines obtained by said FOE measuring circuit system (400) pass through the FOE point; and a parameter memory (56) for storing a predetermined threshold value and the decision result.