cv2.error: OpenCV(4.5.5) D:\a\opencv-python\imgproc\src\color.cpp:182: 错误: (-215:Assertion failed) !_src.empty() in function 'cv:: cvt颜色'答案

【问题标题】：cv2.error: OpenCV(4.5.5) D:\a\opencv-python\imgproc\src\color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor'cv2.error: OpenCV(4.5.5) D:\a\opencv-python\imgproc\src\color.cpp:182: 错误: (-215:Assertion failed) !_src.empty() in function 'cv:: cvt颜色'
【发布时间】：2022-07-18 23:23:08
【问题描述】：

我认为我的写作方式是正确的，但我仍然面临这个错误。请你帮帮我错误如下 - Tkinter 回调中的异常回溯（最近一次通话最后）： call 中的文件“C:\Users\swpr4\AppData\Local\Programs\Python\Python310\lib\tkinter_init_.py”，第 1921 行返回 self.func(*args) 文件“c:\Users\swpr4\OneDrive\Desktop\face_recognition system\face_recognition.py”，第 109 行，在 face_recog img=recognize(img,clf,faceCascade) 文件“c:\Users\swpr4\OneDrive\Desktop\face_recognition system\face_recognition.py”，第 98 行，在识别中 coord=draw_boundray(img,faceCascade,1.1,10,(255,25,255),"Face",clf) 文件“c:\Users\swpr4\OneDrive\Desktop\face_recognition system\face_recognition.py”，第 49 行，在 draw_boundray gray_image=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY) cv2.error: OpenCV(4.5.5) D:\a\opencv-python\opencv-python\opencv\modules\imgproc\src\color.cpp:182: error: (-215:Assertion failed) !_src.empty () 在函数'cv::cvtColor'中

from tkinter import*
# from tkinter import ttk
from PIL import Image,ImageTk
from tkinter import messagebox
import cv2
import os
import numpy as np
import mysql.connector





class Face_recognition:  
    def __init__(self,root):
        self.root=root
        self.root.geometry("1540x790+0+0")
        self.root.title("face Recognition System")

        title_lbl=Label(self.root,text="FACE RECOGNITION",font=("times new roman",35,"bold"),bg="white",fg="red")
        title_lbl.place(x=0,y=0,width=1530,height=45)


        # 1st image
        img_top=Image.open(r"college_images\face_detector1.jpg")
        img_top=img_top.resize((650,700),Image.ANTIALIAS)
        self.photoimg_top=ImageTk.PhotoImage(img_top)

        f_lbl=Label(self.root,image=self.photoimg_top)
        f_lbl.place(x=0,y=55,width=650,height=700)

        # 2nd image

        img_bottom=Image.open(r"college_images\facial_recognition_system_identification_digital_id_security_scanning_thinkstock_858236252_3x3-100740902-large.jpg")
        img_bottom=img_bottom.resize((950,700),Image.ANTIALIAS)
        self.photoimg_bottom=ImageTk.PhotoImage(img_bottom)

        f_lbl=Label(self.root,image=self.photoimg_bottom)
        f_lbl.place(x=650,y=55,width=950,height=700)

        #button
        b1_1=Button(f_lbl,text="Face Recognition",command=self.face_recog, cursor="hand2",font=("times new roman",18,"bold"),bg="red",fg="white")
        b1_1.place(x=365,y=620,width=200,height=40)

    #==========================face recognition =============================#

    def face_recog(self):
        def draw_boundray(img,classifier,scaleFactor,minNeighbors,color,text,clf):
            gray_image=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
            feature=classifier.detectMultiScale(gray_image,scaleFactor,minNeighbors)

            coord=[]

            for(x,y,w,h) in feature:
                cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),3)
                id,predict=clf.predict(gray_image[y:y+h,x:x+w])
                confidence=int((100*(1-predict/300)))

                conn=mysql.connector.connect(host="localhost",username="root",password="root1234",database="face_recognizer")
                my_cursor=conn.cursor()

                my_cursor.execute("select Name from student where Student_Id="+str(id))
                n=my_cursor.fetchone()
                n="+".join(n)

                my_cursor.execute("select Roll from student where Student_Id="+str(id))
                r=my_cursor.fetchone()
                r="+".join(r)

                my_cursor.execute("select Dep from student where Student_Id="+str(id))
                d=my_cursor.fetchone()
                d="+".join(d)

                # my_cursor.execute("select Division from student where Student_Id="+str(id))
                # di=my_cursor.fetchone()
                # di="+".join(di)

                 

                if confidence>77:
                    cv2.putText(img,f"Roll:{r}",(x,y-55),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    cv2.putText(img,f"Name:{n}",(x,y-30),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    cv2.putText(img,f"Department:{d}",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    #cv2.putText(img,f"Division:{di}",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)
                
                else:
                    cv2.rectangle(img,(x,y),(x+w,y+h),(0,0,255),3)
                    cv2.putText(img,"Unknown Face",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                coord=[x,y,w,h]

            return coord

        def recognize(img,clf,faceCascade):
            coord=draw_boundray(img,faceCascade,1.1,10,(255,25,255),"Face",clf)
            return img

        faceCascade=cv2.CascadeClassifier("haarcascade_frontalface_default.xml")
        clf=cv2.face.LBPHFaceRecognizer_create()
        clf.read("classifire.xml")

        video_cap=cv2.VideoCapture(0)

        while True:
            ret,img=video_cap.read()
            img=recognize(img,clf,faceCascade)
            cv2.imshow("Welcome To Face Recognition",img)

            if cv2.waitKey(1)==13:
                break
            video_cap.release()
            cv2.destroyAllWindows()


if __name__ == "__main__":
    root=Tk()
    obj=Face_recognition(root)
    root.mainloop()

from tkinter import*
# from tkinter import ttk
from PIL import Image,ImageTk
from tkinter import messagebox
import cv2
import os
import numpy as np
import mysql.connector





class Face_recognition:  
    def __init__(self,root):
        self.root=root
        self.root.geometry("1540x790+0+0")
        self.root.title("face Recognition System")

        title_lbl=Label(self.root,text="FACE RECOGNITION",font=("times new roman",35,"bold"),bg="white",fg="red")
        title_lbl.place(x=0,y=0,width=1530,height=45)


        # 1st image
        img_top=Image.open(r"college_images\face_detector1.jpg")
        img_top=img_top.resize((650,700),Image.ANTIALIAS)
        self.photoimg_top=ImageTk.PhotoImage(img_top)

        f_lbl=Label(self.root,image=self.photoimg_top)
        f_lbl.place(x=0,y=55,width=650,height=700)

        # 2nd image

        img_bottom=Image.open(r"college_images\facial_recognition_system_identification_digital_id_security_scanning_thinkstock_858236252_3x3-100740902-large.jpg")
        img_bottom=img_bottom.resize((950,700),Image.ANTIALIAS)
        self.photoimg_bottom=ImageTk.PhotoImage(img_bottom)

        f_lbl=Label(self.root,image=self.photoimg_bottom)
        f_lbl.place(x=650,y=55,width=950,height=700)

        #button
        b1_1=Button(f_lbl,text="Face Recognition",command=self.face_recog, cursor="hand2",font=("times new roman",18,"bold"),bg="red",fg="white")
        b1_1.place(x=365,y=620,width=200,height=40)

    #==========================face recognition =============================#

    def face_recog(self):
        def draw_boundray(img,classifier,scaleFactor,minNeighbors,color,text,clf):
            gray_image=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
            feature=classifier.detectMultiScale(gray_image,scaleFactor,minNeighbors)

            coord=[]

            for(x,y,w,h) in feature:
                cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),3)
                id,predict=clf.predict(gray_image[y:y+h,x:x+w])
                confidence=int((100*(1-predict/300)))

                conn=mysql.connector.connect(host="localhost",username="root",password="root1234",database="face_recognizer")
                my_cursor=conn.cursor()

                my_cursor.execute("select Name from student where Student_Id="+str(id))
                n=my_cursor.fetchone()
                n="+".join(n)

                my_cursor.execute("select Roll from student where Student_Id="+str(id))
                r=my_cursor.fetchone()
                r="+".join(r)

                my_cursor.execute("select Dep from student where Student_Id="+str(id))
                d=my_cursor.fetchone()
                d="+".join(d)

                # my_cursor.execute("select Division from student where Student_Id="+str(id))
                # di=my_cursor.fetchone()
                # di="+".join(di)

                 

                if confidence>77:
                    cv2.putText(img,f"Roll:{r}",(x,y-55),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    cv2.putText(img,f"Name:{n}",(x,y-30),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    cv2.putText(img,f"Department:{d}",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                    #cv2.putText(img,f"Division:{di}",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)
                
                else:
                    cv2.rectangle(img,(x,y),(x+w,y+h),(0,0,255),3)
                    cv2.putText(img,"Unknown Face",(x,y-5),cv2.FONT_HERSHEY_COMPLEX,0.8,(255,255,255),3)

                coord=[x,y,w,h]

            return coord

        def recognize(img,clf,faceCascade):
            coord=draw_boundray(img,faceCascade,1.1,10,(255,25,255),"Face",clf)
            return img

        faceCascade=cv2.CascadeClassifier("haarcascade_frontalface_default.xml")
        clf=cv2.face.LBPHFaceRecognizer_create()
        clf.read("classifire.xml")

        video_cap=cv2.VideoCapture(0)

        while True:
            ret,img=video_cap.read()
            img=recognize(img,clf,faceCascade)
            cv2.imshow("Welcome To Face Recognition",img)

            if cv2.waitKey(1)==13:
                break
            video_cap.release()
            cv2.destroyAllWindows()


if __name__ == "__main__":
    root=Tk()
    obj=Face_recognition(root)
    root.mainloop()

【问题讨论】：

标签： python face-recognition

【解决方案1】：

这是一个非常肤浅的答案，但我可以从代码中追溯 OpenCv 在调用 cv2.cvtColor(img,cv2.COLOR_BGR2GRAY) 时抛出此问题，这表明图像数据可能为空：

https://docs.opencv.org/3.4/d8/dfe/classcv_1_1VideoCapture.html#a473055e77dd7faa4d26d686226b292c1

【讨论】：

【解决方案2】：

如果您在 Windows 上工作，则必须使用 \\ it 而不是 \Linux 。我知道这很痛苦，但出于某种原因，微软喜欢用这样的细微差别来惹恼程序员。你不是唯一一个忘记的人，我很难学会这一点。

【讨论】：