Method and apparatus for identifying objects depicted in a videostream

• US 6,266,442 B1
• Filed: 10/23/1998
• Issued: 07/24/2001
• Est. Priority Date: 10/23/1998
• Status: Expired due to Term

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Facet Technology Corp.
• Inventors: Retterath, James Eugene, Laumeyer, Robert Anthony
• Primary Examiner(s): Johns, Andrew W.
• Assistant Examiner(s): AZARIAN, SEYED H
• Time in patent office: 1005 Days
• Field of Search: 382/190, 382/163, 382/164, 382/165, 382/104, 382/155, 382/159, 382/162, 382/166
• US Class Current: 382/190
• CPC Class Codes: G06K 9/00818 Recognising traffic signs
• CPC Class Codes: G06K 9/4609 by matching or filtering
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/74 involving reference images or patches

Abstract

The present invention relates to an apparatus for rapidly analyzing frame(s) of digitized video data which may include objects of interest randomly distributed throughout the video data and wherein said objects are susceptible to detection, classification, and ultimately identification by filtering said video data for certain differentiable characteristics of said objects. The present invention may be practiced on pre-existing sequences of image data or may be integrated into an imaging device for real time, dynamic, object identification, classification, logging/counting, cataloging, retention (with links to stored bitmaps of said object), retrieval, and the like. The present invention readily lends itself to the problem of automatic and semi-automatic cataloging of vast numbers of objects such as traffic control signs and utility poles disposed in myriad settings. When used in conjunction with navigational or positional inputs, such as GPS, an output from the inventive system indicates the identity of each object, calculates object location, classifies each object by type, extracts legible text appearing on a surface of the object (if any), and stores a visual representation of the object in a form dictated by the end user/operator of the system. The output lends itself to examination and extraction of scene detail which cannot practically be successfully accomplished with just human viewers operating video equipment, although human intervention can still be used to help judge and confirm a variety of classifications of certain instances and for types of identified objects.

Claims

1. A method of segmenting at least two image frames depicting at least one road sign comprising the steps of:

receiving at least two image frames that each depict at least a single common road sign;

applying a fuzzy logic color filter to said at least two image frames to segment as separate image portions from said at least two image frames each region that contains a group of pixels all having a color-set from a set of at least one pre-selected road sign color-sets; and

saving to a separate memory location each of said separate image portions.

2. The method of claim 1 further comprising prior to completing the step of applying the fuzzy logic color filter, the step of converting said at least two image frames from a native color space to a single color space portion of a L*u*v color space and wherein the fuzzy logic color filter provides a value output signal that is at a maximum for only said set of at least one pre-selected road sign color-sets.

3. The method of claim 2, wherein the value output signals of the fuzzy logic color filter for each pixel are determined by location in said L*u*v color space and wherein the value output signals are assigned to a minimal set of mathematically described colors representing all of the legal color names and combinations of said set of at least one pre-selected road sign color sets.

4. The method of claim 1 further comprising:

receiving for said at least two image frames an identifier tag; and

linking said identifier tag to each of said image portions stored in said separate memory locations.

5. The method of claim 4 wherein said identifier tag includes at least a one of the following items:

camera number, frame number, camera location coordinates or camera orientation.

6. The method of claim 1 wherein the fuzzy logic color filter segments the separate image portions such that each image portion contains a range of colors related to said color set whereby variations between colors of individual pixels are allowed to exist in said group of pixels that comprise each image portion.