Img.find_template function

OpenMV Boards
1

I use the img.find_template function to find the template, but when looking for multiple templates, the speed will drop, is there any way to improve the efficiency of multiple templates?

2

Have you tried diamond search ?

3

Yes, I use the box to find, the code is as follows, I want to know how to improve the efficiency and speed of the search under multiple templates.

r1 = img.find_template(template1, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r2 = img.find_template(template2, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r3 = img.find_template(template3, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r4 = img.find_template(template4, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r5 = img.find_template(template5, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r6 = img.find_template(template6, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))
r7 = img.find_template(template7, 0.70, step=4, search=SEARCH_EX) #, roi=(10, 0, 60, 60))


if r1:
img.draw_rectangle(r1)
elif r2:
img.draw_rectangle(r2)
elif r3:
img.draw_rectangle(r3)
elif r4:
img.draw_rectangle(r4)
elif r5:
img.draw_rectangle(r5)
elif r6:
img.draw_rectangle(r6)
elif r7:
img.draw_rectangle(r7)

4

That’s the exhaustive search, try:

r1 = img.find_template(template1, search=SEARCH_DS)
5

Hi!
I don’t understand the error (OSError: Could not find the path),
The files are located on the camera…(template = image.Image(“/1.pgm”))

6

Removing the leading slash.

7

Deleted…, now it complains about the line: (r = img.find_template(template, 0.70, step=4, search=SEARCH_EX) # , roi=(10, 0, 60, 60)))
TypeError: Can’t convert list to type

8

What’s the whole script?

9

template_matching_1.py


import time
import sensor
import image
from image import SEARCH_EX


sensor.reset()

sensor.set_contrast(1)
sensor.set_gainceiling(16)
sensor.set_framesize(sensor.QQVGA)

sensor.set_pixformat(sensor.GRAYSCALE)

template = image.Image("1.pgm")

clock = time.clock()

while True:
    clock.tick()
    img = sensor.snapshot()

    r = img.find_template(template, 0.70, step=4, search=SEARCH_EX)  
    if r:
        img.draw_rectangle(r)

    print(clock.fps())
10

Please provide me the pgm image and what you are testing against, e.g. the frame buffer.

11

Problem solved..
The picture had no contrast..
Thank you very much!