python实现从视频中选帧截取图片并输出

import cv2
import os


def extract_frames(video_path, output_folder, num_frames=40):
    # 确保输出文件夹存在
    if not os.path.exists(output_folder):
        os.makedirs(output_folder)

    # 打开视频
    video_capture = cv2.VideoCapture(video_path)
    if not video_capture.isOpened():
        print("无法打开视频，请检查路径是否正确！")
        return

    total_frames = int(video_capture.get(cv2.CAP_PROP_FRAME_COUNT))
    if total_frames == 0:
        print("视频文件无帧，请检查文件是否损坏！")
        return

    frame_rate = total_frames // num_frames
    print(f"总帧数: {total_frames}, 每隔 {frame_rate} 帧截取一张图片")

    count = 0
    saved_count = 0

    while True:
        ret, frame = video_capture.read()
        if not ret:
            break

        # 每隔 frame_rate 保存
        if count % frame_rate == 0 and saved_count < num_frames:
            output_path = os.path.join(output_folder, f"image_{saved_count:03d}.jpg")
            success = cv2.imwrite(output_path, frame)
            if success:
                print(f"成功保存图片: {output_path}")
                saved_count += 1
            else:
                print(f"保存失败: {output_path}")

        count += 1

    video_capture.release()
    print("视频帧提取完成！")


# 示例用法
video_path = r"" # 使用绝对路径
output_folder = r""# 使用绝对路径
extract_frames(video_path, output_folder, num_frames=30)