形状检测和颜色检测，颜色能识别蓝色圆，形状却圈住红色的圆

[uye4]

# Single Color RGB565 Blob Tracking Example
#
# This example shows off single color RGB565 tracking using the OpenMV Cam.

import sensor, image, time,pyb,math
from pyb import UART,Pin,Timer
import json
uart=pyb.UART(3,115200,timeout_char=1000)


threshold_index = 0 # 0 for red, 1 for green, 2 for blue

# Color Tracking Thresholds (L Min, L Max, A Min, A Max, B Min, B Max)
# The below thresholds track in general red/green/blue things. You may wish to tune them...
thresholds = [(30, 100, 15, 127, 15, 127), # generic_red_thresholds
              (30, 100, -64, -8, -32, 32), # generic_green_thresholds
              (0, 100, -16, 127, -128, -31)] # generic_blue_thresholds
#-------------------摄像头初始化-----------------------------
sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 2000)
sensor.set_auto_gain(False) # must be turned off for color tracking
sensor.set_auto_whitebal(False) # must be turned off for color tracking
clock = time.clock()
#start = pyb.millis() # get value of millisecond counter  获取毫秒计数器的值

# Only blobs that with more pixels than "pixel_threshold" and more area than "area_threshold" are
# returned by "find_blobs" below. Change "pixels_threshold" and "area_threshold" if you change the
# camera resolution. "merge=True" merges all overlapping blobs in the image.
def find_max(blobs):
    max_size=0
    for blob in blobs:
     if blob[2]*blob[3]>max_size:
        max_blob=blob
        max_size=blob[2]*blob[3]
    return max_blob
   #if(blob[5]==sensor.width/2) and (blob[6]==sensor.height/2):
while(True):
    clock.tick()
    img = sensor.snapshot().lens_corr(strength = 1.8, zoom = 1.0)#摄像头畸变矫正
    for c in img.find_circles(threshold=3500,x_margin=20,y_margin=20,
    r_margin=20,r_min=2,r_max=100,r_step=2):
        area=(c.x()-c.r(),c.y()-c.r(),2*c.r(),2*c.r())
        statistics=img.get_statistics(roi=area)
        #print(statistics)

    blobs = img.find_blobs([thresholds[2]])
    #print(img.width()/2,img.height()/2)

    if blobs:
        img.draw_circle((c.x(),c.y(),c.r()),color=(0,0,255))
        max_blob=find_max(blobs)
        #img.draw_rectangle(max_blob.rect())
        img.draw_cross(max_blob.cx(),max_blob.cy())
        output_str="[%d,%d]"%(max_blob.cx(),max_blob.cy())
        print('you send:',output_str)
        uart.write( output_str+'\r\n')
    else:
         #img.draw_rectangle(area,color=(255,0,0))
         print('not found!')

[kidswong999]

代码的逻辑有一些问题。

你说的现象，直接的原因是
img.draw_circle((c.x(),c.y(),c.r()),color=(0,0,255))
这个c是上面的for c in img.find_circles里面的，而不是find_blobs里面的。

改成img.draw_circle((max_blob.cx(),max_blob.cy(),max_blob.w()/2),color=(0,0,255))会圈出来蓝色的色块。

PS: 你上面的for c in img.find_circles也有很大的问题，如果画面中有两个圆，结果可能不是你预期的那样。

[uye4]

报错了，我想先颜色检测后再霍夫圆，不知道怎么解决你说的for c in img.find_circles的问题