@kidswong999 那我接单片机的话高低电平能快速反映不
S
s6d3
@s6d3
0
声望
4
楼层
609
资料浏览
0
粉丝
0
关注
s6d3 发布的帖子
-
IO口设置高低有点小问题
我想用人脸检测到 就给外界一个高电平,我用P0改写代码发现在置高电平时 万用表检测电平是从0缓慢上升到3.3 有没有什么办法能够稍微快速 或者让电平保持3.3一段时间?加上time.sleep()也是缓慢上升。
import sensor, time, image, pyb p = pyb.Pin("P0", pyb.Pin.OUT_PP) # Reset sensor sensor.reset() # Sensor settings sensor.set_contrast(1) sensor.set_gainceiling(16) # HQVGA and GRAYSCALE are the best for face tracking. sensor.set_framesize(sensor.HQVGA) sensor.set_pixformat(sensor.GRAYSCALE) #注意人脸识别只能用灰度图哦 # Load Haar Cascade # By default this will use all stages, lower satges is faster but less accurate. face_cascade = image.HaarCascade("frontalface", stages=25) #image.HaarCascade(path, stages=Auto)加载一个haar模型。haar模型是二进制文件, #这个模型如果是自定义的,则引号内为模型文件的路径;也可以使用内置的haar模型, #比如“frontalface” 人脸模型或者“eye”人眼模型。 #stages值未传入时使用默认的stages。stages值设置的小一些可以加速匹配,但会降低准确率。 print(face_cascade) # FPS clock clock = time.clock() while (True): clock.tick() # Capture snapshot img = sensor.snapshot() # Find objects. # Note: Lower scale factor scales-down the image more and detects smaller objects. # Higher threshold results in a higher detection rate, with more false positives. objects = img.find_features(face_cascade, threshold=0.75, scale=1.35) #image.find_features(cascade, threshold=0.5, scale=1.5),thresholds越大, #匹配速度越快,错误率也会上升。scale可以缩放被匹配特征的大小。 if(objects): p.high() time.sleep(300) else: p.low() #在找到的目标上画框,标记出来 # Draw objects for r in objects: img.draw_rectangle(r) # Print FPS. # Note: Actual FPS is higher, streaming the FB makes it slower. print(clock.fps())