opencv讀取視頻幀

# 提起整個訓練集的視頻,並每隔5幀將圖片保存起來
import cv2
import os

TIMESEP = 25  # 讀取的幀數為：25幀

def capture(root, timeSep):
    # 視頻文件大概是5秒，一秒為28幀左右，一個視頻共有130幀,最終讀取25幀
    i = 0  # 進行計數
    c = 0  # 圖片名稱
    counter = 0 # 讀取的幀數
    # success = False  # 讀取圖片是否成功
    cap = cv2.VideoCapture(root)
    if cap.isOpened():
        success, frame = cap.read()
        # 保存圖片到指定文件夾
        cv2.imwrite('/home/wbx/photoes/' + str(c) + '.jpg', frame)
        c += 1
        i += 1
        counter += 1

    while success:
        success, frame = cap.read()
        if i % 5 == 0:  # 每5幀讀取一次
            cv2.imwrite('/home/wbx/photoes/' + str(c) + '.jpg', frame)
            c += 1
            counter += 1
        if counter == timeSep:
            break
        i += 1
        cv2.waitKey(1)

Myroot = "/home/wbx/RLVD/Violence/V_90.mp4"
main_dir = "/Users/wbx/Downloads/RLVD"
savePath = "/home/wbx/RLVD"

def findRoot(main_dir):
    rootList = []
    flagList = []
    for x in os.listdir(main_dir):
        print(type(x))
        if x != ".DS_Store":
            td = main_dir + '/' + x + '/'
            print(td)
            for file in os.listdir(td):
                # print(file)
                filePath = os.path.join(td, file)  # 獲取視頻的完整路徑 
                # print(filePath)
                rootList.append(filePath)
                flag = file.split('_')
                print(type(flag[0])) # flag[0]為：NV 或者 V 可以用來判斷是否是暴力行為
                flagList.append(flag[0])
    return rootList, flagList


capture(root=Myroot, timeSep=TIMESEP)

rootList, flagList = findRoot(main_dir=main_dir) 
print(len(rootList))