将 txt 文件中每一帧的文本写入视频

Question

我有一个 txt 文件，其中包含视频中每一帧的注释（所以 "number of rows" == "number of frames"）。现在我想将每一行的文本写入视频中相应的帧（到某个角落）——有没有办法使用 ffmpeg（或类似的免费工具）做到这一点？

Answer 1

借助 drawtext，您可以使用 libfreetype 库在视频顶部绘制文本字符串或来自指定文件的文本。

见https://ffmpeg.org/ffmpeg-filters.html#drawtext

Answer 2

import cv2
# reading text file with text. each line index is frame pos
with open('frames.txt') as f:
    frames = {k: v for k, v in enumerate(f.readlines())}

cap = cv2.VideoCapture('sample.mp4')
fps = cap.get(cv2.CAP_PROP_FPS)
w = cap.get(cv2.CAP_PROP_FRAME_WIDTH)
h = cap.get(cv2.CAP_PROP_FRAME_HEIGHT)

fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('output.avi', fourcc, fps, (int(w), int(h)))
font = cv2.FONT_HERSHEY_SIMPLEX

while cap.isOpened():
    ret, frame = cap.read()
    if ret:
        frame_no = cap.get(cv2.CAP_PROP_POS_FRAMES)
        if frame_no in frames:
            cv2.putText(frame, frames[frame_no], (10, 500), font, 4, (255, 255, 255), 2, cv2.LINE_AA)
        out.write(frame)
    else:
        break


cap.release()
out.release()
cv2.destroyAllWindows()

将 txt 文件中每一帧的文本写入视频

write text for each frame from txt file onto video

video

ffmpeg