Image capture enhancement using dynamic control image

• US 9,594,943 B1
• Filed: 07/19/2016
• Issued: 03/14/2017
• Est. Priority Date: 09/01/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Brain, Alister J.
• Primary Examiner(s): PRABHAKHER, PRITHAM DAVID
• Application Number:
  US15/214,073
• Publication Number:
  US 20170061197A1
• Time in Patent Office: 238 Days
• Field of Search: 348/143
• US Class Current: 1/1
• CPC Class Codes: G06T 2207/10048 Infrared image
• CPC Class Codes: G06T 2207/20224 Image subtraction
• CPC Class Codes: G06T 2207/30201 Face
• CPC Class Codes: G06T 2207/30232 Surveillance
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/30 Determination of transform parameters for the alignment of images, i.e. image registration
• CPC Class Codes: G06V 10/141 Control of illumination
• CPC Class Codes: G06V 10/22 by selection of a specific region containing or referencing a pattern; Locating or processing of specific regions to guide the detection or recognition
• CPC Class Codes: G06V 40/16 Human faces, e.g. facial parts, sketches or expressions
• CPC Class Codes: G06V 40/166 using acquisition arrangements
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/81 for suppressing or minimising disturbance in the image signal generation
• CPC Class Codes: H04N 25/40 Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

Embodiments of the present invention provide systems and methods for image capture with infrared emitters, with associated computer control and processing for providing consistent and high quality image data. Image data of consecutive frames from a camera is obtained, with a first frame being taken during an emission of infrared light directed at a scene to be captured by the camera and a second frame being taken without an emission of infrared light. The consecutive frames provide a dynamic control image of the captured scene. The image data may be used to support photometric sampling techniques used in building geometric models for subject recognition in camera imagery in variable lighting environments.

Claims

1. A computer-implemented method for image capture enhancement, comprising:

activating a sequence of infrared emissions, by one or more emitters in an environment space monitored by a camera for capturing images of the environment space, wherein the sequence of infrared emissions is synchronized with a frame counter of the camera;

receiving captured image frames from the camera, wherein the captured image frames comprise a first frame captured during an emission, and a second frame, adjacent to the first frame, captured outside the emission;

subtracting the second frame from the first frame to provide an image of a reflected infrared component;

removing, from the reflected infrared component, a previously obtained background image of the environment space to enhance a subject in the image; and

outputting a resultant image for processing.

2. The method of claim 1, further comprising:

receiving a plan view captured image from a plan view camera of the environment space, wherein the plan view captured image is captured during an emission;

identifying a subject in the plan view captured image; and

positioning the subject in two dimensions of a plan of the environment space.

3. The method of claim 2, further comprising:

recalibrating the resultant image based on the positioning of the subject and a previously obtained infrared light intensity map of the environment space.

4. The method of claim 1, further comprising:

obtaining a background image of the environment space by capturing image frames during a sequence of emissions without a subject in the environment space; and

obtaining an infrared light intensity map of the environment space.

5. The method of claim 1, wherein activating a sequence of infrared emissions, by one or more emitters in an environment space, comprises:

firing emissions from the one or more emitters in turn to obtain multiple captured frame images having different light angles on a subject in the environment space.

6. The method of claim 1, wherein activating a sequence of infrared emissions is in response to detecting a subject in the environment space.

7. The method of claim 1, further comprising:

receiving captured image frames from a plurality of cameras at different locations for capturing the environment space; and

wherein outputting a resultant image outputs multiple resultant images for further processing.

8. The method of claim 1, further comprising:

receiving camera telemetry data for a position and an orientation of a non-static camera, for each captured image frame.