license_plate_recognition/openvino_infer.py

import cv2
import matplotlib.pyplot as plt
import numpy as np
from openvino.runtime import Core
import os
import time
import copy
from PIL import Image, ImageDraw, ImageFont
import argparse

def cv_imread(path):
    img=cv2.imdecode(np.fromfile(path,dtype=np.uint8),-1)
    return img

def allFilePath(rootPath,allFIleList):
    fileList = os.listdir(rootPath)
    for temp in fileList:
        if os.path.isfile(os.path.join(rootPath,temp)):
            # if temp.endswith("jpg"):
            allFIleList.append(os.path.join(rootPath,temp))
        else:
            allFilePath(os.path.join(rootPath,temp),allFIleList)

mean_value,std_value=((0.588,0.193))#识别模型均值标准差
plateName=r"#京沪津渝冀晋蒙辽吉黑苏浙皖闽赣鲁豫鄂湘粤桂琼川贵云藏陕甘青宁新学警港澳挂使领民航危0123456789ABCDEFGHJKLMNPQRSTUVWXYZ险品"

def rec_pre_precessing(img,size=(48,168)): #识别前处理
    img =cv2.resize(img,(168,48))
    img = img.astype(np.float32)
    img = (img/255-mean_value)/std_value
    img = img.transpose(2,0,1)
    img = img.reshape(1,*img.shape)
    return img

def decodePlate(preds):        #识别后处理
    pre=0
    newPreds=[]
    preds=preds.astype(np.int8)[0]
    for i in range(len(preds)):
        if preds[i]!=0 and preds[i]!=pre:
            newPreds.append(preds[i])
        pre=preds[i]
    plate=""
    for i in newPreds:
        plate+=plateName[int(i)]
    return plate

def load_model(onnx_path):
    ie = Core()
    model_onnx = ie.read_model(model=onnx_path)
    compiled_model_onnx = ie.compile_model(model=model_onnx, device_name="CPU")
    output_layer_onnx = compiled_model_onnx.output(0)
    return compiled_model_onnx,output_layer_onnx

def get_plate_result(img,rec_model,rec_output):
    img =rec_pre_precessing(img)
    # time_b = time.time()
    res_onnx = rec_model([img])[rec_output]
    # time_e= time.time()
    index =np.argmax(res_onnx,axis=-1)  #找出最大概率的那个字符的序号
    plate_no = decodePlate(index)
    # print(f'{plate_no},time is {time_e-time_b}')
    return plate_no


def get_split_merge(img):  #双层车牌进行分割后识别
    h,w,c = img.shape
    img_upper = img[0:int(5/12*h),:]
    img_lower = img[int(1/3*h):,:]
    img_upper = cv2.resize(img_upper,(img_lower.shape[1],img_lower.shape[0]))
    new_img = np.hstack((img_upper,img_lower))
    return new_img


def order_points(pts):
    rect = np.zeros((4, 2), dtype = "float32")
    s = pts.sum(axis = 1)
    rect[0] = pts[np.argmin(s)]
    rect[2] = pts[np.argmax(s)]
    diff = np.diff(pts, axis = 1)
    rect[1] = pts[np.argmin(diff)]
    rect[3] = pts[np.argmax(diff)]
    return rect


def four_point_transform(image, pts):
    rect = order_points(pts)
    (tl, tr, br, bl) = rect
    widthA = np.sqrt(((br[0] - bl[0]) ** 2) + ((br[1] - bl[1]) ** 2))
    widthB = np.sqrt(((tr[0] - tl[0]) ** 2) + ((tr[1] - tl[1]) ** 2))
    maxWidth = max(int(widthA), int(widthB))
    heightA = np.sqrt(((tr[0] - br[0]) ** 2) + ((tr[1] - br[1]) ** 2))
    heightB = np.sqrt(((tl[0] - bl[0]) ** 2) + ((tl[1] - bl[1]) ** 2))
    maxHeight = max(int(heightA), int(heightB))
    dst = np.array([
        [0, 0],
        [maxWidth - 1, 0],
        [maxWidth - 1, maxHeight - 1],
        [0, maxHeight - 1]], dtype = "float32")
    M = cv2.getPerspectiveTransform(rect, dst)
    warped = cv2.warpPerspective(image, M, (maxWidth, maxHeight))
 
    # return the warped image
    return warped

def my_letter_box(img,size=(640,640)):
    h,w,c = img.shape
    r = min(size[0]/h,size[1]/w)
    new_h,new_w = int(h*r),int(w*r)
    top = int((size[0]-new_h)/2)
    left = int((size[1]-new_w)/2)
    
    bottom = size[0]-new_h-top
    right = size[1]-new_w-left
    img_resize = cv2.resize(img,(new_w,new_h))
    img = cv2.copyMakeBorder(img_resize,top,bottom,left,right,borderType=cv2.BORDER_CONSTANT,value=(114,114,114))
    return img,r,left,top

def xywh2xyxy(boxes):
    xywh =copy.deepcopy(boxes)
    xywh[:,0]=boxes[:,0]-boxes[:,2]/2
    xywh[:,1]=boxes[:,1]-boxes[:,3]/2
    xywh[:,2]=boxes[:,0]+boxes[:,2]/2
    xywh[:,3]=boxes[:,1]+boxes[:,3]/2
    return xywh

def my_nms(boxes,iou_thresh):
    index = np.argsort(boxes[:,4])[::-1]
    keep = []
    while index.size >0:
        i = index[0]
        keep.append(i)
        x1=np.maximum(boxes[i,0],boxes[index[1:],0])
        y1=np.maximum(boxes[i,1],boxes[index[1:],1])
        x2=np.minimum(boxes[i,2],boxes[index[1:],2])
        y2=np.minimum(boxes[i,3],boxes[index[1:],3])
        
        w = np.maximum(0,x2-x1)
        h = np.maximum(0,y2-y1)

        inter_area = w*h
        union_area = (boxes[i,2]-boxes[i,0])*(boxes[i,3]-boxes[i,1])+(boxes[index[1:],2]-boxes[index[1:],0])*(boxes[index[1:],3]-boxes[index[1:],1])
        iou = inter_area/(union_area-inter_area)
        idx = np.where(iou<=iou_thresh)[0]
        index = index[idx+1]
    return keep

def restore_box(boxes,r,left,top):
    boxes[:,[0,2,5,7,9,11]]-=left
    boxes[:,[1,3,6,8,10,12]]-=top

    boxes[:,[0,2,5,7,9,11]]/=r
    boxes[:,[1,3,6,8,10,12]]/=r
    return boxes

def detect_pre_precessing(img,img_size):
    img,r,left,top=my_letter_box(img,img_size)
    # cv2.imwrite("1.jpg",img)
    img =img[:,:,::-1].transpose(2,0,1).copy().astype(np.float32)
    img=img/255
    img=img.reshape(1,*img.shape)
    return img,r,left,top

def post_precessing(dets,r,left,top,conf_thresh=0.3,iou_thresh=0.5):#检测后处理
    choice = dets[:,:,4]>conf_thresh
    dets=dets[choice]
    dets[:,13:15]*=dets[:,4:5]
    box = dets[:,:4]
    boxes = xywh2xyxy(box)
    score= np.max(dets[:,13:15],axis=-1,keepdims=True)
    index = np.argmax(dets[:,13:15],axis=-1).reshape(-1,1)
    output = np.concatenate((boxes,score,dets[:,5:13],index),axis=1) 
    reserve_=my_nms(output,iou_thresh) 
    output=output[reserve_] 
    output = restore_box(output,r,left,top)
    return output

def rec_plate(outputs,img0,rec_model,rec_output):
    dict_list=[]
    for output in outputs:
        result_dict={}
        rect=output[:4].tolist()
        land_marks = output[5:13].reshape(4,2)
        roi_img = four_point_transform(img0,land_marks)
        label = int(output[-1])
        if label==1:  #代表是双层车牌
            roi_img = get_split_merge(roi_img)
        plate_no = get_plate_result(roi_img,rec_model,rec_output) #得到车牌识别结果
        result_dict['rect']=rect
        result_dict['landmarks']=land_marks.tolist()
        result_dict['plate_no']=plate_no
        result_dict['roi_height']=roi_img.shape[0]
        dict_list.append(result_dict)
    return dict_list



def cv2ImgAddText(img, text, left, top, textColor=(0, 255, 0), textSize=20):
    if (isinstance(img, np.ndarray)):  #判断是否OpenCV图片类型
        img = Image.fromarray(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
    draw = ImageDraw.Draw(img)
    fontText = ImageFont.truetype(
        "fonts/platech.ttf", textSize, encoding="utf-8")
    draw.text((left, top), text, textColor, font=fontText)
    return cv2.cvtColor(np.asarray(img), cv2.COLOR_RGB2BGR)

def draw_result(orgimg,dict_list):
    result_str =""
    for result in dict_list:
        rect_area = result['rect']
        
        x,y,w,h = rect_area[0],rect_area[1],rect_area[2]-rect_area[0],rect_area[3]-rect_area[1]
        padding_w = 0.05*w
        padding_h = 0.11*h
        rect_area[0]=max(0,int(x-padding_w))
        rect_area[1]=min(orgimg.shape[1],int(y-padding_h))
        rect_area[2]=max(0,int(rect_area[2]+padding_w))
        rect_area[3]=min(orgimg.shape[0],int(rect_area[3]+padding_h))

        height_area = result['roi_height']
        landmarks=result['landmarks']
        result = result['plate_no']
        result_str+=result+" "
        # for i in range(4):  #关键点
        #     cv2.circle(orgimg, (int(landmarks[i][0]), int(landmarks[i][1])), 5, clors[i], -1)
        
        if len(result)>=6:
            cv2.rectangle(orgimg,(rect_area[0],rect_area[1]),(rect_area[2],rect_area[3]),(0,0,255),2) #画框
            orgimg=cv2ImgAddText(orgimg,result,rect_area[0]-height_area,rect_area[1]-height_area-10,(0,255,0),height_area)
    # print(result_str)
    return orgimg

def get_second(capture):
    if capture.isOpened():
        rate = capture.get(5)   # 帧速率
        FrameNumber = capture.get(7)  # 视频文件的帧数
        duration = FrameNumber/rate  # 帧速率/视频总帧数 是时间，除以60之后单位是分钟
        return int(rate),int(FrameNumber),int(duration)    

if __name__=="__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument('--detect_model',type=str, default=r'weights/plate_detect.onnx', help='model.pt path(s)')  #检测模型
    parser.add_argument('--rec_model', type=str, default='weights/plate_rec.onnx', help='model.pt path(s)')#识别模型
    parser.add_argument('--image_path', type=str, default='imgs', help='source') 
    parser.add_argument('--img_size', type=int, default=640, help='inference size (pixels)')
    parser.add_argument('--output', type=str, default='result1', help='source') 
    opt = parser.parse_args()
    file_list=[]
    file_folder=opt.image_path
    allFilePath(file_folder,file_list)
    rec_onnx_path =opt.rec_model
    detect_onnx_path=opt.detect_model
    rec_model,rec_output=load_model(rec_onnx_path)
    detect_model,detect_output=load_model(detect_onnx_path)
    count=0
    img_size=(opt.img_size,opt.img_size)
    begin=time.time()
    save_path=opt.output
    if not os.path.exists(save_path):
        os.mkdir(save_path)
    for pic_ in file_list:
    
        count+=1
        print(count,pic_,end=" ")
        img=cv2.imread(pic_)
        time_b = time.time()
        if img.shape[-1]==4:
            img = cv2.cvtColor(img,cv2.COLOR_BGRA2BGR)
        img0 = copy.deepcopy(img)
        img,r,left,top = detect_pre_precessing(img,img_size) #检测前处理
        # print(img.shape)
        det_result = detect_model([img])[detect_output]
        outputs = post_precessing(det_result,r,left,top) #检测后处理
        time_1 = time.time()
        result_list=rec_plate(outputs,img0,rec_model,rec_output)
        time_e= time.time()
        print(f'耗时 {time_e-time_b} s')
        ori_img = draw_result(img0,result_list)
        img_name = os.path.basename(pic_)
        save_img_path = os.path.join(save_path,img_name)
        
        cv2.imwrite(save_img_path,ori_img)
print(f"总共耗时{time.time()-begin} s")

    # video_name = r"plate.mp4"
    # capture=cv2.VideoCapture(video_name)
    # fourcc = cv2.VideoWriter_fourcc(*'MP4V') 
    # fps = capture.get(cv2.CAP_PROP_FPS)  # 帧数
    # width, height = int(capture.get(cv2.CAP_PROP_FRAME_WIDTH)), int(capture.get(cv2.CAP_PROP_FRAME_HEIGHT))  # 宽高
    # out = cv2.VideoWriter('2result.mp4', fourcc, fps, (width, height))  # 写入视频
    # frame_count = 0
    # fps_all=0
    # rate,FrameNumber,duration=get_second(capture)
    # # with open("example.csv",mode='w',newline='') as example_file:
    #     # fieldnames = ['车牌', '时间']
    #     # writer = csv.DictWriter(example_file, fieldnames=fieldnames, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
    #     # writer.writeheader()
    # if capture.isOpened():
    #     while True:
    #         t1 = cv2.getTickCount()
    #         frame_count+=1
    #         ret,img=capture.read()
    #         if not ret:
    #             break
    #         # if frame_count%rate==0:
    #         img0 = copy.deepcopy(img)
    #         img,r,left,top = detect_pre_precessing(img,img_size) #检测前处理
    #         # print(img.shape)
    #         det_result = detect_model([img])[detect_output]
    #         outputs = post_precessing(det_result,r,left,top) #检测后处理
    #         result_list=rec_plate(outputs,img0,rec_model,rec_output)
    #         ori_img = draw_result(img0,result_list)
    #         t2 =cv2.getTickCount()
    #         infer_time =(t2-t1)/cv2.getTickFrequency()
    #         fps=1.0/infer_time
    #         fps_all+=fps
    #         str_fps = f'fps:{fps:.4f}'
    #         out.write(ori_img)
    #         cv2.putText(ori_img,str_fps,(20,20),cv2.FONT_HERSHEY_SIMPLEX,1,(0,255,0),2)
    #         cv2.imshow("haha",ori_img)
    #         cv2.waitKey(1)

    #         # current_time = int(frame_count/FrameNumber*duration)
    #         # sec = current_time%60
    #         # minute = current_time//60
    #         # for result_ in result_list:
    #         #     plate_no = result_['plate_no']
    #         #     if not is_car_number(pattern_str,plate_no):
    #         #         continue
    #         #     print(f'车牌号:{plate_no},时间:{minute}分{sec}秒')
    #         #     time_str =f'{minute}分{sec}秒'
    #         #     writer.writerow({"车牌":plate_no,"时间":time_str})
    #         # out.write(ori_img)
            
            
    # else:
    #     print("失败")
    # capture.release()
    # out.release()
    # cv2.destroyAllWindows()
    # print(f"all frame is {frame_count},average fps is {fps_all/frame_count}")