Oct 21 Devlog 2

detecting the circle in the gauge

i have fixed the fps issue previously and getting stable fps to perform my task through a webcam its mentioned in first devlog so i moved on to next part
so after that i started working on detecting gauge and its main pin
first i started with detecting the circle and middle point of the gauge so i used gauge image for that for now and then i apply same algorithm in video input
so i understanded the geometry of circle to detect circle in the gauge
then i get to know that we have prepare the image first for the detection in which we apply grayscale filter and blur to image , blur to reduce the noise
after that preparing i used the “cv2.HoughCircles()” library of open cv this library search the circular shapes in images it have multiple parameter we can tweak to get desirable outcome
after using that library to detect circle i draw the circle in the image and displayed the output in terminal
after detecting the main circle in gauge finding the pin mid point is easy just put an dot on middle of circle(repented by red)

to detect the main gauge needle we have to mask the dial gray scale the region and using edge detection to highlight the boundaries and line (photos added)
then identify the candidate line around the gauge so they all not mix-up (only detects straight lines )
then i visualized the lines
i faced like problem in unpacking this detected line coordinates because it is structed as a single integer
so i lookup for solution and come accross it we have to use “fatten()” it coverts arrays into one-dimensional array i didnt get it that much but its like assigning multiple coordinate at single point
and i got lines on the images but all are not filtered too many line the out put is usable
so we have to use filters like in the sence a set rules which line can pass through which are not
i mused midpoint formula to calculate the closest line to the mid point to detect the needle
after that i used angle calculation too
after that i used all of this filtration and all that and combine it together and got the output
in last now its detecting the needle and dial of the gauge given in input

(some time is inflated due to some error in hackatime i hope it solve asap it tracked my unrelated grokbot session time in this project )