OPENCV-功能可以绘制文字到画布

Question

我正在从相机中检测到一张脸，并在其周围绘制矩形。下面的代码：

face_cascade = cv2.CascadeClassifier('face_classifier.xml')
def detect(gray, frame): 
    faces = face_cascade.detectMultiScale(gray, 1.3, 5) 
    for (x, y, w, h) in stops: # For each detected face:
        cv2.rectangle(frame, (x, y), (x+w, y+h), (255, 0, 0), 2) 
    return frame 
video_capture = cv2.VideoCapture(0)
while True: 
    _, frame = video_capture.read() 
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    canvas = detect(gray, frame) 
    cv2.imshow('Video', canvas) 
    if cv2.waitKey(1) & 0xFF == ord('q'): 
        break 

OPENCV中是否有任何功能可以打印文本？当它在屏幕上检测到脸时说"嗨"？

谢谢您的时间。

Answer 1

应该在提出问题之前先完成此操作，但是在谷歌搜索并尝试了几件事之后，这是解决方案：

face_cascade = cv2.CascadeClassifier('face_classifier.xml')
def detect(gray, frame): 
    faces = face_cascade.detectMultiScale(gray, 1.3, 5) 
    for (x, y, w, h) in stops: # For each detected face:
        cv2.rectangle(frame, (x, y), (x+w, y+h), (255, 0, 0), 2) 
        font = cv2.FONT_HERSHEY_COMPLEX_SMALL
        cv2.putText(frame,'Hello There!',(x+w, h),font, 0.8,(255,0,0),2,cv2.LINE_AA)
    return frame 
video_capture = cv2.VideoCapture(0)
while True: 
    _, frame = video_capture.read() 
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    canvas = detect(gray, frame) 
    cv2.imshow('Video', canvas) 
    if cv2.waitKey(1) & 0xFF == ord('q'): 
        break 

这将添加"你好！"在检测框架矩形的右上角。