Image processing method for a driver assistance system of a motor vehicle for detecting and classifying at least one portion of at least one predefined image element

• US 9,030,558 B2
• Filed: 06/21/2010
• Issued: 05/12/2015
• Est. Priority Date: 06/29/2009
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Wuerz-Wessel, Alexander
• Primary Examiner(s): LI, TRACY Y
• Application Number:
  US13/380,764
• Publication Number:
  US 20120162429A1
• Time in Patent Office: 1,786 Days
• Field of Search: 348/148
• US Class Current: 348/148
• CPC Class Codes: G06F 18/211 Selection of the most significant subset of features
• CPC Class Codes: G06V 10/771 Feature selection, e.g. selecting representative features from a multi-dimensional feature space
• CPC Class Codes: G06V 20/582 of traffic signs

Abstract

In an image processing method for a driver assistance system for detecting and classifying a portion of a predefined image element having a road sign in a digital image captured by an image sensor of the driver assistance system, first scale-invariant image features and their relative geometric arrangement with respect to one another are computed based on at least one image region of the digital image to be searched, after which a classifier compares the first scale-invariant image features and their relative geometric arrangement with respect to one another to stored and/or learned second scale-invariant image features and their relative geometric arrangement with respect to one another which are computed based on the at least one predefined image element.

Claims

1. An image processing method for a driver assistance system of a motor vehicle for detecting and classifying at least one portion of a predefined image element having a road sign in a selected digital image captured by an image sensor of the driver assistance system, comprising:

computing first scale-invariant image features and relative geometric arrangement of the first scale-invariant image features with respect to one another based on at least one image region of the digital image;

comparing, by a classifier unit of the driver assistance system, the first scale-invariant image features and the relative geometric arrangement of the first scale-invariant image features with respect to one another to second scale-invariant image features and relative geometric arrangement of the second scale-invariant image features with respect to one another which are computed based on the predefined image element; and

determining, by the classifier unit, the at least one portion of the predefined image element of the digital image to be detected and classified if the comparing produces a match,

wherein a measure for the correctness of the detection and classification is determined, and wherein a number of pixels of the second scale-invariant image features associated with pixels of the first scale invariant image features is used as the measure for the correctness of the detection and classification.