Method and system for coding information on a roadway surface subject to motion blur

• US 8,378,799 B2
• Filed: 12/17/2009
• Issued: 02/19/2013
• Est. Priority Date: 06/30/2009
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Yim, Raymond, Perli, Samuel David, Porikli, Fatih, Zhang, Jinyun
• Primary Examiner(s): HOFSASS, JEFFERY A
• Application Number:
  US12/640,949
• Publication Number:
  US 20100327064A1
• Time in Patent Office: 1,160 Days
• Field of Search: 340/425.5, 340/438, 340/435, 340/436, 340/901, 340/905, 382/104, 404/12
• US Class Current: 340/425.5
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1417 2D bar codes
• CPC Class Codes: G06K 7/1473 error correction

Abstract

Symbols in information are encoded as a codeword using a differential orthogonal code. The codeword is stored in a substrate. A moving sensor acquires an image of the codeword in the substrate and decodes the codeword using a balanced differential decoder. The codeword can be painted as lane markings on a road surface.

Claims

1. A method for coding information, comprising a processor for performing steps of the method, comprising the steps of:

defining a code, wherein the code is a differential orthogonal code;

encoding symbols of the information into a codeword using the code; and

storing the codeword in a substrate, wherein the substrate is a road surface.

2. The method of claim 1, wherein the codeword is paint on the road surface as lane markings.

3. The method of claim 2, wherein the paint has multiple colors and intensities to represent the symbols of the codeword.

4. The method of claim 1, wherein the information relates to geographical locations.

5. The method of claim 1, wherein the information relates to traveling directions along the road surface.

6. The method of claim 1, wherein the information relates to road conditions.

7. A system for coding information, comprising a processor for performing steps of the method, comprising the steps of:

means for defining a code, wherein the code is a differential orthogonal code;

means for encoding symbols of the information into a codeword using the code;

means for storing the codeword in a substrate, wherein the substrate is a road surface;

a sensor configured to acquire an image of the codeword in the substrate by a sensor; and

a balanced differential decoder configured to decode the codeword in the image.

8. The method of claim 7, wherein the sensor is moving relative to the road surface, and the image is subject to motion blur.

9. The method of claim 7, wherein the sensor is a camera mounted on a vehicle traveling on the road surface.

10. The method of claim 7, wherein the sensor is a camera, and wherein the camera detects a location of the lane marking using minimal spread thresholding and by corner detection.