Detection and positioning method for train water injection port

Patent metadata

Field	Value
Publication number	US-11066088-B2
Application number	US-201817270873-A
Country	US
Kind code	B2
Filing date	Dec 13, 2018
Priority date	Dec 13, 2018
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A detection and positioning method for a train water injection port includes: acquiring train water injection port video images, and performing threshold segmentation on the train water injection port video images to obtain binarized train water injection port video images; processing the binarized train water injection port video images and matching the processed binarized train water injection port video images with a train water injection port template image; detecting a position of the water injection port in the train water injection port video image and comparing the position with a pre-set position range where the water injection port is located; and if the position and the pre-set position range have been matched, then transmitting a matching valid signal to a mechanical device control module to control a mechanical device to move or stop and start or stop water injection.

First claim

What is claimed is:

1. A detection and positioning method for a train water injection port, comprising:
acquiring continuous train water injection port video images, and performing a threshold segmentation on the continuous train water injection port video images to obtain binarized train water injection port video images;
processing the binarized train water injection port video images and matching the processed binarized train water injection port video images with a train water injection port template image;
detecting a position of the water injection port in the processed binarized train water injection port video images and comparing the position with a pre-set position range, wherein the water injection port is located in the pre-set position range; and
if the position and the pre-set position range have been matched, then transmitting a matching valid signal to a mechanical device control module to control a mechanical device to move or stop and start or stop water injection.

2. The detection and positioning method for the train water injection port according to claim 1 , wherein
the step of performing the threshold segmentation on the train water injection port video images to obtain the binarized train water injection port video images specifically comprises:
performing a binarization segmentation on the continuous train water injection port video images according to a binarization threshold, and sequentially generating an m×n video image window pixel by pixel according to a step of 1 by using the binarized train water injection port video images.

3. The detection and positioning method for the train water injection port according to claim 2 , wherein
in a position of the m×n video image window, a position of a pixel in a first row and a first column in an entire frame image in the m×n video image window is marked as coordinates P(i,j) of the position of the m×n video image window.

4. The detection and positioning method for the train water injection port according to claim 3 , wherein
a process of obtaining the binarization threshold specifically comprises:
counting a number of pixels corresponding to each grayscale value in a current frame image in the binarized train water injection port video images to form an abstract grayscale histogram, and calculating a binarization threshold with an optimal segmentation effect according to the abstract grayscale histogram.

5. The detection and positioning method for the train water injection port according to claim 4 , further comprising:
determining a maximum value and a first grayscale value corresponding to the maximum value in the abstract grayscale histogram, determining a secondary peak value on a right side of the first grayscale value and a second grayscale value corresponding to the secondary peak value in the abstract grayscale histogram, calculating a histogram between the first grayscale value and the second grayscale value to obtain a minimum valley value and a third gray scale value corresponding to the minimum valley value, and defining the third grayscale value as the binarization threshold.

6. The detection and positioning method for the train water injection port according to claim 5 , wherein
the step of comparing the position with the pre-set position range, wherein the water injection port is located in the pre-set position range, and if the position and the pre-set position range have been matched, then transmitting the matching valid signal to the mechanical device control module to control the mechanical device to move or stop and start or stop the water injection specifically comprises:
comparing the m×n video image window with the train water injection port template image, calculating a total number of pixels with the same pixel value in the same position of the m×n video image window and the train water injection port template image, recording the total number as a window matching result, performing a matching degree verification on the window matching result and performing a window matching position verification on the window matching result in combination with the position P(i,j) of the m×n video image window to obtain a matching valid signal, and transmitting the matching valid signal to the mechanical device control module.

7. The detection and positioning method for the train water injection port according to claim 6 , wherein
the step of comparing the m×n video image window with the train water injection port template image, calculating the total number of the pixels with the same pixel value in the same position of the m×n video image window and the train water injection port template image, and recording the total number as the window matching result specifically comprises:
sequentially storing m rows in the binarized train water injection port video image into m FIFOs;
shifting data read from the m FIFOs to left as shift bits to m n-bit shift registers;
performing a bitwise XNOR on the m n-bit shift registers and m n-bit template registers;
adding up XNOR results of each row;
counting a number of pixels with the same pixel value in each corresponding n-bit register to obtain n row matching results; and
summing up the n row matching results of the corresponding m n-bit registers to count the number of the pixels with the same pixel value in the same position of the m×n video image window and the train injection port template image as the window matching result.

8. The detection and positioning method for the train water injection port according to claim 7 , further comprising:
verifying the window matching result, and comparing the window matching result with a set matching threshold as follows: if the window matching result is greater than the set matching threshold, then performing pixel number matching, and then performing position matching, and if the window matching result is less than the set matching threshold, then waiting for an arrival of a next clock window matching result and continuing to perform the pixel number matching.

9. The detection and positioning method for the train water injection port according to claim 8 , further comprising:
performing position verification on the m×n video image window successful in the pixel number matching, and comparing a position matching result P(i,j) with a set window position range as follows: if the position matching result P(i,j) is within the set window position range, then determining the position matching as successful, and transmitting the matching valid signal to the mechanical device control module, and if the position matching result P(i,j) is not within the set window position range, then waiting for next verification.

10. The detection and positioning method for the train water injection port according to claim 2 , further comprising:
measuring light intensity in a surrounding environment in real time to obtain a measured ambient illuminance, and when the measured ambient illuminance is lower than a set illuminance threshold, controlling an external lighting lamp to be turned on and off.

11. The detection and positioning method for the train water injection port according to claim 3 , further comprising:
measuring light intensity in a surrounding environment in real time to obtain a measured ambient illuminance, and when the measured ambient illuminance is lower than a set illuminance threshold, controlling an external lighting lamp to be turned on and off.

12. The detection and positioning method for the train water injection port according to claim 4 , further comprising:
measuring light intensity in a surrounding environment in real time to obtain a measured ambient illuminance, and when the measured

Assignees

• Univ Xidian

Inventors

• Zhou Huixin
• Xiang Pei
• Deng Baokai
• Yu Yue
• Guo Lixin
• Zhao Dong
• Qin Hanlin
• Wang Bingjian
• Song Jiangluqi
• Li Huan
• Yao Bo
• Lai Rui
• Jia Xiuping
• Zhou Jun

Classifications

• G06V10/758

  Involving statistics of pixels or of feature values, e.g. histogram matching · CPC title

• G06V20/00

  Scenes; Scene-specific elements (control of digital cameras H04N23/60) · CPC title

• B61L27/57

  for vehicles or trains, e.g. trackside supervision of train conditions · CPC title

• G06T7/74 Primary

  involving reference images or patches · CPC title

• H04N23/71

  Circuitry for evaluating the brightness variation · CPC title