Moving object image pickup apparatus

• US 5,889,878 A
• Filed: 07/28/1995
• Issued: 03/30/1999
• Est. Priority Date: 07/29/1994
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Togashi, Yuichi
• Primary Examiner(s): CHANG, JON CARLTON
• Application Number:
  US08/508,896
• Time in Patent Office: 1,341 Days
• Field of Search: 382/103, 382/104, 382/106, 382/107, 382/173, 348/169, 348/170, 348/171, 348/172, 348/148, 348/149, 348/154, 348/155, 348/352, 348/345, 348/362-365, 348/222, 348/363, 340/958, 340/435, 340/903, 340/937
• US Class Current: 382/103
• CPC Class Codes: G06T 2207/10021 Stereoscopic video; Stereoscopic image sequence
• CPC Class Codes: G06T 2207/20068 Projection on vertical or horizontal image axis
• CPC Class Codes: G06T 2207/30236 Traffic on road, railway or crossing
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/136 involving thresholding
• CPC Class Codes: G06T 7/194 involving foreground-background segmentation
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80

Abstract

An ITV camera picks up an image of an image pickup region including a moving object and a fixed object which serves as a reference to measure a distance. Images are fetched through the ITV camera at a first aperture which discriminates between a background and the fixed object and a second aperture which discriminates between the background and the moving object. The images thus fetched are added together and edges (outlines) of the fixed object and the moving object from the added image. A distance between the fixed object and the moving object is calculated from the extracted edges. The optimal aperture, enlargement ratio and focal lengths are automatically determined in a short period of time in accordance with the image pickup region and an optimal image is provided.

Claims

1. A moving object position detecting apparatus comprising:

image pickup means for picking up an image of an image pickup region including a moving object and a fixed object which serves as a reference to measure a distance, said image pickup means including an aperture variable mechanism to vary the aperture of a lens;

moving object detecting means for detecting whether the moving object is present in the image pickup region;

first fetching means for fetching the image from the image pickup means, with the aperture of the image pickup means set to a first state, thereby to discriminate between a background and the fixed object, the first fetching means including means for fetching an image in response to detection by the moving object detecting means;

second fetching means for fetching the image from the image pickup means, with the aperture of the image pickup means set to a second state which is different from said first state, thereby to discriminate between the background and the moving object, the second fetching means including means for fetching an image in response to detection by the moving detecting means;

converting means for converting the image fetched by the first and second fetching means to image data including luminance data representing image luminance;

image data adding means for adding luminance data of the image fetched by the first fetching means and converted by the converting means and luminance data of the image fetched by the second fetching means and converted by the converting means;

extracting means for extracting images of the fixed object and the moving object based on added luminance data of the image data obtained by the image data adding means; and

distance calculating means for calculating a distance between the fixed object and the moving object.

2. The apparatus according to claim 1, further comprising:

an image memory for storing images supplied from the first and second fetching means; and

histogram producing means for producing luminance histograms of the images stored in the image memory, wherein;

the first fetching means include aperture control means for determining an optimal aperture for picking up images of the fixed object and background and controlling the aperture of the lens to the optimal aperture by means of the aperture-variable mechanism, with reference to the luminance histograms produced by the histogram producing means.

3. The apparatus according to claim 1, wherein the image data adding means include means for weighting at least one of the images fetched by the first and second fetching means in accordance with a difference between the first and second apertures, and adding the weighted image.

5. The apparatus according to claim 1, wherein:

the image pickup means includes;

first image pickup means having the aperture set in the first state to discriminate between the background and the fixed object; and

second image pickup means having the aperture set in the second state to discriminate between the background and the moving object; and

wherein;

the first fetching means include means for fetching an image from the first image pickup means; and

the second fetching means include means for fetching an image from the second image pickup means at the same time the first fetching means fetch the image.

6. The apparatus according to claim 1, further comprising

means for varying a gain of an image signal supplied from the image pickup means;

wherein;

the first fetching means include means for fetching the image at a first gain which discriminates between the background and the fixed object; and

the second fetching means include means for fetching the image at a second gain which discriminates between the background and the moving object.

7. The apparatus according to claim 1, wherein:

the image pickup means includes;

first image pickup means having a first image signal gain which discriminates between the background and the fixed object; and

second image pickup means having a second image signal gain which discriminates between the background and the moving object; and

wherein;

the first fetching means include means for fetching an image from the first image pickup means; and

the second fetching means include means for fetching an image from the second image pickup means at the same time the first fetching means fetch the image.

4. A moving object position detecting apparatus comprising:

image pickup means for picking up an image of an image pickup region including a moving object and a fixed object which serves as a reference to measure a distance, said image pickup means including an aperture variable mechanism to vary the aperture of a lens;

first fetching means for fetching the image from the image pickup means, with the aperture of the image pickup means set to a first state, thereby to discriminate between a background and the fixed object;

second fetching means for fetching the image from the image pickup means, with the aperture of the image pickup means set to a second state which is different from said first state, thereby to discriminate between the background and the moving object;

converting means for converting the image fetched by the first and second fetching means to image data including luminance data representing image luminance;

image data adding means for adding luminance data of the image fetched by the first fetching means and converted by the converting means and luminance data of the image fetched by the second fetching means and converted by the converting means;

extracting means for extracting images of the fixed object and the moving object based on added luminance data of the image data obtained by the image data adding means, the extracting means including edge extracting means for extracting desired edges of the fixed object and the moving object in the added image obtained by the image data adding means; and

distance calculating means for calculating a distance between the fixed object and the moving object, the distance calculating means including translating means for translating the number of pixels between the desired edges of the fixed object and the moving object to an actual distance therebetween, based on a distance between the image pickup means and the fixed object.

8. A moving object position detecting apparatus comprising:

image pickup means including;

a lens; and

an aperture-variable mechanism for changing an aperture of the lens;

said image pickup means picking up an image of an image pickup region including a moving object and a fixed object which serves as a reference to measure a distance;

first fetching means for fetching the image from the image pickup means at a first aperture which discriminates between a background and the fixed object;

second fetching means comprising;

(a) aperture controlling means for controlling the aperture-variable mechanism of the image pickup means to change the aperture of the lens from the first aperture to a second aperture;

(b) third fetching means for fetching a plurality of images at different apertures in a transient period in which the aperture of the lens is changed to the second aperture; and

(c) means for selecting an optimal image from the plurality of images fetched by the third fetching means;

image adding means for adding the images fetched by the first and second fetching means;

extracting means for extracting images of the fixed object and the moving object from an added image obtained by the image adding means; and

distance calculating means for calculating a distance between the fixed object and the moving object.

9. The apparatus according to claim 8, wherein the image adding means include means for weighting at least one of the images fetched by the first and second fetching means in accordance with a difference between the first and second apertures, and adding the weighted image.

10. The apparatus according to claim 8, further comprising moving object detecting means for detecting whether the moving object is present in the image pickup region, wherein the second fetching means include means for fetching an image in reply to a detection result of the moving object detecting means.

11. A moving object position detecting apparatus comprising:

image pickup means for picking up an image of an image pickup region, said image pickup means including a lens having an aperture which can be varies;

moving object detecting means for detecting whether the moving object is present in the image pickup region;

converting means for converting the images picked up by the image pickup means to image data including luminance data representing image luminance;

storing means for storing, when the moving object detecting means detects that the moving object is present in the image pickup region, first image data picked up by the image pickup means in a state where the aperture of the image pickup means is comparatively narrow and second image data picked up by the image pickup means in a state where the aperture of the image pickup means is comparatively wide;

adding means for adding luminance data of the first and second image data stored in the storing means; and

extracting means for extracting an image of a moving object based on added luminance data of the image data obtained by the image data adding means.