import cv2 # OpenCV
import tkinter.filedialog # Python文件对话框
filename = tkinter.filedialog.askopenfilename() # 弹出对话框选择需要裁剪的视频文件
cap = cv2.VideoCapture(filename) # 打开视频文件
frames = cap.get(cv2.CAP_PROP_FRAME_COUNT) # 获得视频文件的帧数
fps = cap.get(cv2.CAP_PROP_FPS) # 获得视频文件的帧率
width = cap.get(cv2.CAP_PROP_FRAME_WIDTH) # 获得视频文件的帧宽
height = cap.get(cv2.CAP_PROP_FRAME_HEIGHT) # 获得视频文件的帧高
# 创建保存视频文件类对象
fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('D:/Project/fish_data/鱼类研究/fishdata/5/Black_porgy/c32.mp4v', fourcc, fps, (int(width), int(height)))
# 计算视频长度/s
video_length = frames / fps
print('start and stop must < %.1f' % video_length) # 提示用户输入变量的范围
start = float(input('Input an start time/s:'))
stop = float(input('Input an stop time/s:'))
# 设置帧读取的开始位置
cap.set(cv2.CAP_PROP_POS_FRAMES, start * fps)
pos = cap.get(cv2.CAP_PROP_POS_FRAMES) # 获得帧位置
while (pos <= stop * fps):
ret, frame = cap.read() # 捕获一帧图像
out.write(frame) # 保存帧
pos = cap.get(cv2.CAP_PROP_POS_FRAMES)
cap.release()
out.release()
一个小错误
OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 12 and format 'mp4 / MP4 (MPEG-4 Part 14)' OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'
解决:
直接将输出的.MP4格式写成 .mp4v就好了
输出指定的帧数直接在fps上面修改即可
参考: