Distance Estimation Using Multi-Camera Device

• US 20160048968A1
• Filed: 04/06/2014
• Published: 02/18/2016
• Est. Priority Date: 04/08/2013
• Status: Active Grant

• Current Assignee: Augmented Reality Solutions Ltd.
• Original Assignee: Cimagine Media Ltd. (Snap, Inc.)
• Inventors: Egri, Ozi, Zak, Eyal
• Granted Patent: US 10,192,312 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01C 3/085 with electronic parallax measurement
• CPC Class Codes: G03B 35/02 by sequential recording
• CPC Class Codes: G03B 35/10 having single camera with stereoscopic-base-defining system
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 2207/30041 Eye; Retina; Ophthalmic
• CPC Class Codes: G06T 2207/30244 Camera pose
• CPC Class Codes: G06T 7/593 from stereo images
• CPC Class Codes: G06V 10/147 Details of sensors, e.g. sensor lenses fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19
• CPC Class Codes: G06V 10/17 using hand-held instruments
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/51 Housings

Abstract

A method and apparatus for measuring a distance to an object using a device (100) having at least two cameras (104, 106) is described. One or more first images including the object are acquired by a first camera of the device and one or more first reference images are acquired by a second camera of the device, while the device is in a first position. One or more second images including the object and one or more second reference images are acquired by cameras of the device, while the device is in a second position, different from the first position. Based on the first and second reference images, information of the displacement of at least one camera of the device between the first and second positions are determined. The distance from the device to the object is calculated based on the first and second images including the object and the determined information on the displacement of the at least one camera.

Claims

1. A method of measuring a distance to an object, by a device having at least two cameras, comprising:

acquiring one or more first images including the object by a first camera of the device and one or more first reference images by a second camera of the device, while the device is in a first position;

acquiring one or more second images including the object and one or more second reference images, by cameras of the device, while the device is in a second position, different from the first position;

determining, based on the first and second reference images, information on the displacement of at least one camera of the device between the first and second positions; and

calculating the distance from the device to the object, based on the first and second images including the object and the determined information on the displacement of the at least one camera said calculation based on a substantially universal fixed measurement.

2. The method of claim 1, wherein acquiring the one or more second images including the object comprises acquiring by the first camera, through which the one or more first images of the object were acquired.

3. The method of claim 1, wherein acquiring the one or more first images including the object comprises acquiring a plurality of images while the device is in the first position and generating a single image including the object from the plurality of acquired images.

4. The method of claim 3, wherein generating a single image including the object from the plurality of acquired images comprises selecting one of the images.

5. The method of claim 3, wherein generating a single image including the object from the plurality of acquired images comprises generating a combination of some or all of the images.

6. The method of claim 3, wherein generating a single image including the object from the plurality of acquired images comprises automatically analyzing the quality of the acquired images and discarding images of a quality below a given threshold.

7. The method of claim 1, comprising displaying to a user instructions directing to change the position of the device to the second position, after acquiring the one or more first images.

8. The method of claim 7, wherein displaying the instructions comprises displaying an indication of an extent of matching of a current image acquired by the second camera, to the first reference image.

9. The method of claim 1, comprising displaying, to a user, a video stream acquired by the second camera, after acquiring the one or more first images, so that the user can use the video stream in directing the device to the second position.

10. The method of claim 1, wherein said substantially universal fixed measurement comprises the size of a body organ and wherein said body organ is included in said first and second reference images.

11. The method of claim 10, wherein said body organ comprises a cornea.

12. The method of claim 1 wherein said substantially universal fixed measurement comprises the distance between said first and second reference-cameras.

14. The method of claim 1, wherein the first and second cameras are on opposite sides of the device.

15. The method of claim 1, wherein the one or more first images including the object and the one or more first reference images are acquired in pairs of reference and object images, the images of each pair being acquired substantially concurrently within less than 1 second.

13. (canceled)

16. A device, comprising:

a housing;

a first camera included in the housing;

a second camera included in the housing; and

a processor, included in the housing, configured to receive one or more first object images including an object, acquired by the first camera, and one or more second object images including the object, to receive one or more first reference images acquired by the second camera and one or more second reference images, to determine a displacement of at least one camera of the device between acquiring the first object image and acquiring the second object image, responsively to the first and second reference images, and to calculate the distance from the device to the object based on the first and second object images and the determined displacement, said calculation based on a substantially universal fixed measurement.

17. The device according to claim 16, wherein the first and second cameras are on opposite sides of the housing.

18. The device according to claim 16, wherein the processor is configured to control the first and second cameras to acquire the images in pairs of concurrently acquired object images and respective reference images.

19. The device according to claim 16, comprising a screen located on a same side of the housing as the second camera.

20. The device according to claims 16, wherein the processor is configured to provide, after receiving the one or more first object images and first reference images, instructions on changing the position of the housing, for acquiring the second object and second reference images.

21. The device according to claims 16, wherein the processor is configured to analyze an input stream provided by the second camera relative to the one or more first reference images, after receiving the one or more first object images and first reference images, in order to determine when the housing is in a position suitable for acquiring the second reference images and the second object images.

22. The device according to claims 16, comprising a screen and wherein the processor is configured to display on the screen, after receiving the one or more first object images and first reference images, a stream of images acquired by the second camera, in order to allow a user to position the housing for acquiring the second images.

23. The device according to claims 16, wherein the processor is configured to determine an extent of relative rotation between the first and second reference images and use the determined extent of relative rotation in determining the displacement of the at least one camera of the device between acquiring the first object image and acquiring the second object image.

24. The device according to claims 16, wherein the processor is configured to determine the displacement by comparing the size of a body organ shown in both the first and second reference images.

25. A computer program product for distance estimation, comprising:

a computer readable non-transitory storage medium having computer readable program code embodied therewith, which when executed by a computer performs;

receives one or more first images including an object and one or more first reference images;

receives one or more second images including the object and one or more second reference image;

determines, based on the first and second reference images, information on a displacement of at least one camera of a device between acquiring the one or more first and one or more second images; and

calculates a distance from the device to the object, based on the first and second images including the object and the determined information on the displacement of the at least one camera, said calculation based on a substantially universal fixed measurement.