循迹画框修改默认颜色

[3iy5]

# Blob Detection Example
#
# This example shows off how to use the find_blobs function to find color
# blobs in the image. This example in particular looks for dark green objects.

import sensor, image, time

# For color tracking to work really well you should ideally be in a very, very,
# very, controlled enviroment where the lighting is constant...
red_threshold_01 = (36, 100, -26, 122, -113, 118)

#设置红色的阈值，括号里面的数值分别是L A B 的最大值和最小值（minL, maxL, minA,
# maxA, minB, maxB），LAB的值在图像左侧三个坐标图中选取。如果是灰度图，则只需
#设置（min, max）两个数字即可。

# You may need to tweak the above settings for tracking green things...
# Select an area in the Framebuffer to copy the color settings.

sensor.reset() # Initialize the camera sensor.
sensor.set_pixformat(sensor.RGB565) # use RGB565.
sensor.set_framesize(sensor.QQVGA) # use QQVGA for speed.
sensor.skip_frames(10) # Let new settings take affect.
sensor.set_auto_whitebal(False)
#关闭白平衡。白平衡是默认开启的，在颜色识别中，需要关闭白平衡。
clock = time.clock() # Tracks FPS.

while(True):
    clock.tick() # Track elapsed milliseconds between snapshots().
    img = sensor.snapshot() # Take a picture and return the image.
    #  pixels_threshold=100, area_threshold=100
    #blobs=img.binary([(100, 255)],invert=False)
    blobs = img.find_blobs([red_threshold_01], area_threshold=150)

    if blobs:
    #如果找到了目标颜色
        print(blobs)
        for b in blobs:
        #迭代找到的目标颜色区域
            # Draw a rect around the blob.
            img.draw_rectangle(b[0:4]) # rect
            #用矩形标记出目标颜色区域
            img.draw_cross(b[5], b[6]) # cx, cy
            #在目标颜色区域的中心画十字形标记


    print(clock.fps()) # Note: Your OpenMV Cam runs about half as fast while
    # connected to your computer. The FPS should increase once disconnected.

请教各位大神，我使用上述代码，它默认寻找的是白色物体，我想修改寻找黑色物品。请问怎么修改修改哪些变量？

十分感谢您在百忙之中回答我的问题。

[yuan]

来自星瞳实验室APP: 黑白色块识别 https://forum.singtown.com/topic/738

[3iy5]

请教各位大神，我使用上述代码，它默认寻找的是白色物体，我想修改寻找黑色物品。请问怎么修改修改哪些变量？
31行代码：

blobs = img.find_blobs([red_threshold_01], area_threshold=150)

修改为

blobs = img.find_blobs([red_threshold_01],invert=True, area_threshold=150)

invert 反转阈值，把阈值以外的颜色作为阈值进行查找；默认情况下是false

[kidswong999]

修改阈值就可以了，教程里有具体的操作步骤。

[3iy5]

@kidswong999
主要是翻转查找对象，需要使用invert参数设置。

[kidswong999]

事实上，你并不需要翻转。。。