Self adjusting stereo camera system

• US 8,085,293 B2
• Filed: 03/14/2001
• Issued: 12/27/2011
• Est. Priority Date: 03/14/2001
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Brodsky, Tomas, Lee, Mi-Suen, Cohen-Solal, Eric
• Primary Examiner(s): Ye, Lin
• Assistant Examiner(s): YODER III, CHRISS S
• Application Number:
  US09/808,377
• Publication Number:
  US 20020158984A1
• Time in Patent Office: 3,940 Days
• Field of Search: 348 42- 60, 348/340, 348169-172, 348344-356, 396/77, 396/78, 359/470, 359/471, 359/472, 359/473, 359/476
• US Class Current: 348/49
• CPC Class Codes: H04N 13/218 using spatial multiplexing
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control thereof

Abstract

A stereo camera system including: a stereo imaging system such as two or more cameras or a camera and a set of angled mirrors, for outputting at least one stereo image; a recognition system for locating an object of interest in the field of view of the stereo imaging system and at least one of a distance of the object of interest from the stereo imaging system and the size of the object of interest; and an adjustor for automatically changing at least one system parameter which affects the spatial resolution of the object of interest based on at least one of the located distance of the object of interest from the stereo imaging system and the size of the object of interest.

Claims

1. A stereo camera system comprising:

stereo imaging means for outputting at least one stereo image, said stereo imaging means including;

a camera;

a set of mirrors angled with respect to each other at a predetermined adjustable angle relative to a centrally located common plane intersecting said camera, each mirror disposed a predetermined adjustable distance from the camera along the common plane, for directing light from an object reflected in said mirrors along a straight line of sight from said minors to the camera, for producing a stereo effect in the output of the camera;

recognition means for analyzing stereo image data from the camera to locate an object of interest in a field of view of the camera and to determine a distance of the object of interest from the stereo imaging means and a size of the object of interest, wherein said analysis of the stereo image data includes extracting multiple features from each image and matching the multiple features across different views; and

adjusting means for automatically changing multiple system parameters independently of one another which affects the spatial resolution of the object of interest in at least one stereo image thereby maximizing a spatial depth resolution of the object based on the located distance of the object from the stereo imaging means and the size of the object, the adjusting means comprising;

angle adjustment means for independently adjusting a first system parameter comprising the angle of the set of mirrors relative to the centrally located plane;

distance adjustment means for independently adjusting a second system parameter comprising the distance between the camera and the set of mirrors; and

focal length adjustment means for independently changing a third system parameter comprising a focal length of the camera,

wherein the adjusting means automatically changes said multiple system parameters independently of one another based on an input signal from the recognition means including information pertaining to at least one of the distance between the camera and the object of interest and the relative size of the object of interest.

2. The stereo camera system of claim 1, wherein the camera is a still camera and the at least one stereo image is a still image.

3. The stereo camera system of claim 1, wherein the camera is a video camera and the at least one stereo image is a sequence of video images.

4. The stereo camera system of claim 1, further comprising a controller for controlling the angle, distance, and focal length adjustment means based on an input signal from the recognition means.

5. The stereo camera system of claim 1, wherein the recognition means is a stereo vision system.

6. The stereo camera system of claim 5, wherein the recognition means analyzes the stereo image data during operation of the camera.

7. The stereo camera system of claim 1, wherein the mirrors have adjacent ends positioned at a common point.

8. The stereo camera system of claim 7, wherein the minors are disposed for directing the light from the object which is reflected in the mirrors directly from the mirrors to the camera.

9. The stereo camera system of claim 1, wherein each of the angle adjustment means, the distance adjustment means, and the focal length adjustment is separately adjustable relative to the other.

10. A method of stereo imaging using a stereo camera system which includes a camera and a pair of minors separated by a separation distance along a base plane and angled by an angle relative to a common central plane, the method comprising:

outputting at least one stereo image of an object of interest from the camera;

analyzing the at least one stereo image output by the camera, wherein said analysis of the at least one stereo image includes;

determining a distance of the object of interest from the camera and a size of the object of interest, and

extracting multiple features from each image and matching the multiple features across different views; and

automatically changing multiple system parameters independently of one another which affects the spatial resolution of the object of interest in at least one stereo image thereby maximizing a spatial depth resolution of the object based on the located distance of the object from the stereo imaging means and the size of the object, wherein changing said multiple system parameters comprises;

adjusting a first system parameter comprising the angle of the pair of mirrors relative to the centrally located plane based on the analysis of the at least one stereo image;

adjusting a second system parameter comprising the distance between the camera and the pair of mirrors based on the analysis of the at least one stereo image; and

changing a third system parameter comprising a focal length of the camera based on the analysis of the at least one stereo image.

11. The method of claim 10, wherein the pair of mirrors abut at and pivot on the common central plane.

12. The method of claim 10, wherein the at least one stereo image includes a series of stereo video images and the analyzing step further includes:

analyzing the series of video images during the outputting of the series of video images.