Video camera with electronic picture stabilizer

• US 5,371,539 A
• Filed: 04/07/1994
• Issued: 12/06/1994
• Est. Priority Date: 10/18/1991
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Iinuma, Toshiya, Kobayashi, Akio, Okino, Toshiyuki
• Primary Examiner(s): Razavi, Michael T.
• Assistant Examiner(s): SHALWALA, BIPIN H
• Application Number:
  US08/224,076
• Time in Patent Office: 243 Days
• Field of Search: 348/155, 348/208, 348/352, 348/413, 348/414, 348/415, 348/416, 348/417, 348/418, 348/699, 348/207
• US Class Current: 348/208.6
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6811 based on the image signal
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory

Abstract

A video camera includes a solid-state image sensing device, and an electric signal from the image sensing device is converted by a camera circuit into a video signal which is further converted into a digital video signal by an A/D converter. The digital video signal is stored in a field memory sequentially field by field under control of a memory control circuit. A motion detecting circuit which receives the digital video signal calculates correlative values for each of a plurality of blocks constituting a whole screen according to a representative point matching method. A microcomputer calculates motion vectors of respective blocks on the basis of correlative value data from the motion detecting circuit and an average motion vector thereof, and calculates "increase", "passing degree" and "variation". The microcomputer further evaluates a reliability of each of the blocks according to a fuzzy inference by utilizing the increase, passing degree and variation as parameters. The memory control circuit determines correction amount for a picture stabilization on the basis of the reliability and the average motion vector.

Claims

1. A video camera, comprising:

an image sensing device;

signal converting means for converting an electric signal from said image sensing device into a digital video signal;

memory means for storing said digital video signal;

correlative value calculating means for calculating correlative values for each of a plurality of blocks within an image field on the basis of said digital video signal in accordance with a representative point matching method;

first calculating means for calculating motion vectors of said plurality of blocks on the basis of said correlative values;

parameter output means for outputting a parameter representative of a status of each of said plurality of blocks on the basis of at least one of said correlative values and said motion vectors,

wherein said parameter output means includes passing degree calculating means for calculating a passing degree that is an index representative of a time period until said correlative values outputted from the said correlative value calculating means become reliable,

wherein said parameter output means includes increase calculating means for calculating an increase that is an index representative of a time period during when motion vectors having the same direction are succeedingly obtained on the basis of said motion vectors calculated by said first calculating means,

wherein said parameter output means includes variation calculating means for calculating a variation that is an index representative of a degree of a change between a current motion vector and a last motion vector on the basis of said motion vectors calculated by said first calculating means, and

wherein said parameter output means includes isolation value calculating means for calculating an isolation value which is calculated by dividing an absolute value of a difference between the motion vector of each block and the average motion vector with an absolute value of a mean value of an X-direction component and a Y-direction component of the average motion vector;

second calculating means for calculating an average motion vector on the basis of said motion vectors and said parameter, wherein said second calculating means also calculates a mean value of said motion vectors of said plurality of blocks on the basis of said parameter;

memory control means for reading said digital video signal from said memory means according to addresses determined on the basis of said average motion vector;

first determining means for determining whether or not each of said plurality of blocks is invalid on the basis of said parameter, wherein said second calculating means calculates said average motion vector on the basis of motion vectors except a motion vector of a block that is determined invalid by said first determining means;

reliability calculating means for calculating a reliability of each of said plurality of blocks on the basis of said passing degree, said increase and said variation, wherein said reliability calculating means includes fuzzy means for performing a fuzzy inference according to predetermined rules by utilizing said passing degree, said increase and said variation as parameters, wherein said second calculating means calculates said average motion vector on the basis of said reliability and said motion vectors; and

second determining means for determining whether or not a motion vector of each of said plurality of blocks is reliable, wherein said isolation index calculating means calculates said isolation index when it is determined three or more blocks are reliable by said second determining means.

2. A picture stabilizer, comprising:

an image sensing device;

signal converting means for converting an electric signal from said image sensing device into a digital video signal;

memory means for storing said digital video signal;

correlative value calculating means for calculating correlative values for each of a plurality of blocks within an image field on the basis of said digital video signal in accordance with representative points matching method;

first calculating means for calculating motion vectors of said plurality of blocks on the basis of said correlative values;

parameter output means for outputting a parameter representative of a status of each of said plurality of blocks on the basis of at least one of said correlative values and said motion vectors,

wherein said parameter output means includes degree calculating means for calculating a passing degree that is an index representative of a time period until said correlative values outputted from the said correlative value calculating means become reliable,

wherein said parameter output means includes increase calculating means for calculating an increase that is an index representative of a time period during when motion vectors having the same direction are succeedingly obtained on the basis of said motion vectors calculated by said first calculating means,

wherein said parameter output means includes variation calculating means for calculating a variation that is an index representative of a degree of a change between a current motion vector and a last motion vector on the basis of said motion vectors calculated by said first calculating means,

wherein said parameter output means includes isolation calculating means for calculating an isolation that is an index representative of a difference between an average vector and a motion vector of each block with respect to said average vector of motion vectors of said plurality of blocks;

second calculating means for calculating an average motion vector on the basis of said motion vectors and said parameter, wherein said second calculating means calculates a mean value of said motion vectors of said plurality of blocks on the basis of said parameter;

memory control means for reading said digital video signal from said memory means according to addresses determined on the basis of said average motion vector;

first determining means for determining whether or not each of said plurality of blocks is invalid on the basis of said parameter, wherein said second calculating means calculates said average motion vector on the basis of motion vectors except a motion vector of a block that is determined invalid by said first determining means;

reliability calculating means for calculating a reliability of each of said plurality of blocks on the basis of said passing degree, said increase and said variation,

wherein said reliability calculating means includes fuzzy means for performing a fuzzy inference according to predetermined rules by utilizing said passing degree, said increase and said variation as parameter, and

wherein said second calculating means calculates said average motion vector on the basis of said reliability and said motion vectors; and

second determining means for determining whether or not a motion vector of each of said plurality of blocks is reliable, wherein said isolation calculating means calculates said isolation when it is determined three or more blocks are reliable by said second determining means.