公开(公告)号：US10565459B2

公开(公告)日：2020-02-18

申请号：US16011254

申请日：2018-06-18

Applicant: Reflective Measurement Systems Ltd

Inventor： James Mahon

IPC: G06K9/00 ,  G01J1/42 ,  G01N21/55 ,  E01C23/16 ,  G01J1/44 ,  H04N5/225 ,  H04N5/247 ,  H04N9/04

Abstract: A retroreflectivity measurement system comprises a light source arranged to project light across a traffic lane during a measurement run, the light being limited to a particular portion of the visible light spectrum. A camera is selectively sensitive to this light to provide first filtered images and separately selectively sensitive to light at a portion of the spectrum not including the particular portion to provide second filtered images. A controller obtains sequences of first and second filtered images during the measurement run, and identifies within the sequences of images an illuminated road marking; determines a first intensity of the marking from a first filtered image, and a further intensity of the marking from the second filtered images; estimates an ambient intensity of the marking, by applying a scaling factor to the further intensity; and determines a retroreflectivity of the marking as a function of the first and estimated ambient intensities.

公开(公告)号：US20190163992A1

公开(公告)日：2019-05-30

申请号：US16011254

申请日：2018-06-18

Applicant: Reflective Measurement Systems Ltd.

Inventor： James Mahon

IPC: G06K9/00 ,  H04N5/225 ,  H04N9/04 ,  H04N5/247 ,  G01N21/55 ,  G01J1/42 ,  G01J1/44

CPC classification number: G06K9/00798 ,  B60W30/12 ,  B60Y2400/3015 ,  E01C23/163 ,  G01J1/4204 ,  G01J1/44 ,  G01N21/55 ,  G01N2021/551 ,  G01N2201/0216 ,  G06K9/2018 ,  H04N5/2253 ,  H04N5/2256 ,  H04N5/247 ,  H04N9/04

Abstract: A retroreflectivity measurement system comprises a light source arranged to project light across a traffic lane during a measurement run, the light being limited to a particular portion of the visible light spectrum. A camera is selectively sensitive to this light to provide first filtered images and separately selectively sensitive to light at a portion of the spectrum not including the particular portion to provide second filtered images. A controller obtains sequences of first and second filtered images during the measurement run, and identifies within the sequences of images an illuminated road marking; determines a first intensity of the marking from a first filtered image, and a further intensity of the marking from the second filtered images; estimates an ambient intensity of the marking, by applying a scaling factor to the further intensity; and determines a retroreflectivity of the marking as a function of the first and estimated ambient intensities.