目录

ffmpeg按帧截取视频，画质会降低：

截取视频 截取mp4

ffmpeg按帧截取视频，画质会降低：

 ffmpeg -i 5s.mp4 -vf "select='gte(n,18)',setpts=N/FRAME_RATE/TB" -c:v libx264 -crf 18 -preset veryslow -c:a copy output.mp4

截取视频 截取mp4

import randomimport cv2
import imageio# 打开原始视频
video_path = r"E:\data\tiaosheng\0706\5s.mp4"out_path=r"E:\data\tiaosheng\0706\output.mp4"
cap = cv2.VideoCapture(video_path)# 获取帧率和分辨率
fps = cap.get(cv2.CAP_PROP_FPS)
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
total_frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))# 创建 imageio 的写入器
writer = imageio.get_writer(out_path, fps=fps)frame_id = 0
while True:ret, frame = cap.read()if not ret:breakif frame_id >= 18:# OpenCV 是 BGR，imageio 需要 RGBframe_rgb = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)writer.append_data(frame_rgb)frame_id += 1cap.release()
writer.close()