@kidswong999 谢谢

@kidswong999 谢谢

Single Color RGB565 Blob Tracking Example

This example shows off single color RGB565 tracking using the OpenMV Cam.

import sensor, image, time, math

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, 30, 0, 64, -128, 0)] # generic_blue_thresholds

thresholds = [(9, 65, 14, 75, -21, 75), # generic_red_thresholds
(30, 100, -64, -8, -32, 32), # generic_green_thresholds
(0, 30, 0, 64, -128, 0)] # generic_blue_thresholds

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()

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.

while(True):
clock.tick()
img = sensor.snapshot()
for blob in img.find_blobs([thresholds[threshold_index]], pixels_threshold=200, area_threshold=200, merge=True):
# These values depend on the blob not being circular - otherwise they will be shaky.
# if blob.elongation() > 0.5:
# img.draw_edges(blob.min_corners(), color=(255,0,0))
# img.draw_line(blob.major_axis_line(), color=(0,255,0))
# img.draw_line(blob.minor_axis_line(), color=(0,0,255))
# These values are stable all the time.
img.draw_rectangle(blob.rect())
img.draw_cross(blob.cx(), blob.cy())
# Note - the blob rotation is unique to 0-180 only.
# img.draw_keypoints([(blob.cx(), blob.cy(), int(math.degrees(blob.rotation())))], size=20)
print(blob)
print(clock.fps())

@vfap 图片追加如下

@kidswong999 谢谢，代码就是官方的例程，只不过把色块的LAB值改了一下

大家好，我目前要用OpenMV H7的模块去识别仪表盘表针（类似于汽车上的仪表）的角度，有如下问题：
1）最近也看了些资料，建议用线识别的思路，再提取角度，不知道哪能找到相关资料？
2）要是用线识别，角度应该只能是0~179的范围。现在表针的角度超过180，低于360，大家有没有更好的方法。
望诸位高手帮忙指点一二，谢谢！！！

大家好，我目前要用OpenMV H7的模块去识别仪表盘表针（类似于汽车上的仪表）的角度，按照官方教程“视频教程4 - 颜色识别：https://singtown.com/learn/49993/”，更改待识别对象的LAB值，可以识别到表针，但blob中的blob.rotation() 返回色块的旋转角度和实际的对不上。请大家帮忙分析一下，另外有没有其他更好的方法或教程可以借鉴的，谢谢！！！

@kidswong999 谢谢

请问，OpenMV H7的模块串口方面有如下问题：
1、该模块具有几个串口；
2、每个串口的波特率最高能到多少；
3、串口电平标准是TTL电平吗？兼容5V吗？
谢谢！！！

我买的是OpenMV H7的模块（摄像头是OV7725），是不是只能识别红黄蓝三种颜色了，我要识别黑色，不知道可以吗？多谢