Method of Taking Pictures for Generating Three-Dimensional Image Data

• US 20120162390A1
• Filed: 12/18/2011
• Published: 06/28/2012
• Est. Priority Date: 12/24/2010
• Status: Active Grant

• Current Assignee: Chih-Ching Depth X Deep Dimensions Co.
• Original Assignee: Chih-Ching Depth X Deep Dimensions Co.
• Inventors: Chang, Wen-Chin, Chen, Tien-Hsiang, Chang, Chin-Chien
• Granted Patent: US 10,194,129 B2
• Time in Patent Office: Days
• US Class Current: 348/49
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects
• CPC Class Codes: H04N 13/271 wherein the generated image signals comprise depth maps or disparity maps

Abstract

A method of taking pictures for generating three-dimensional image data is disclosed. The method includes continuously illuminating a target object with an environmental light; using an image sensor to receive the light reflected from the target object to generate a first electrical image signal; illuminating the target object with an active light generated from an active light source unit during the period of exposure by the environmental light; using the same image sensor to receive another reflected light to generate a second electrical image signal; using an image processing unit to receive the first and second electrical image signals, convert the first electrical image signal to a two-dimensional image data, and subtract the first electrical image signal from the second electrical image signal to generate three-dimensional depth data; and combining the two-dimensional image data and the three-dimensional depth data to generate the three-dimensional image data.

Claims

1. A method of taking pictures for generating three-dimensional image data, comprising steps of:

illuminating a target object with an environmental light to generate a first image reflected light reflected from said target object;

using an image sensor to receive said first image reflected light through an optical unit;

generating a first electrical image signal by using said image sensor bases on said first image reflected light;

using an active light source unit to generate an active light illuminating said target object which is illuminated by said environmental light during exposure of said image sensor by said first image reflected light, wherein said target object reflects said active light to form a second image reflected light;

using said image sensor through said optical unit to receive said second image reflected light and generate a second electrical image signal;

using an image processing unit to receive said first and second electrical image signals, convert said first electrical image signal to a two-dimensional image data, and subtract said first electrical image signal from said second electrical image signal to generate a three-dimensional electrical depth signal, wherein said three-dimensional electrical depth signal is converted to three-dimensional depth data, wherein said two-dimensional image data represents a plane image of said target object sensed by said image sensor, said plane image comprises a plurality of unit images which are two-dimensional images with colors or gray levels, and said three-dimensional depth data represents a depth or a relative depth between said image sensor and each of said unit images; and

combining said two-dimensional image data and said three-dimensional depth data such that finally an output having a depth image together with a color image is thus obtained.

2. The method as claimed in claim 1, wherein said optical unit comprises an optical glass or lens, and said active light has a specific range of wavelength adapted to said optical unit to pass or be filtered.

3. The method as claimed in claim 1, wherein said active light comprises laser or light generated by light emitting diode(LED) with wavelength within a specific range, comprising at least one of visible, ultraviolet, and infrared light.

4. The method as claimed in claim 1, wherein said active light unit has a flickering frequency less than a frame rate of said image sensor with a constant ratio specified as desired;

said constant ratio is a real number from 0 to 1, but not 0 or 1;

an integral of intensity of said active light within a second is substantially not changed after said constant ratio is specified; and

said integral is proportional to said constant ratio.

5. The method as claimed in claim 1, wherein said active light source unit is switched on/off according to appropriate start and end points of time to meet different specification and design for said image sensor, and said start and end points of time are derived from a synchronized signal related to said exposure of said image sensor.

6. The method as claimed in claim 1, wherein said three-dimensional electrical depth signal has a magnitude which is inversely proportional to said relative depth by N powers of exponent, and N is a real number between 1 and 10.

7. The method as claimed in claim 1, wherein said active light source unit is controlled by said image processing unit to generate said active light.

8. The method as claimed in claim 1, wherein said active light source unit generates said active light according to said image sensor.