To reverse a video using `ffmpeg`, you can use the `reverse` filter for the video stream and the `areverse` filter for the audio stream. Here's a basic command to reverse a video:

```bash
ffmpeg -i input_video.mp4 -vf "reverse" -af "areverse" output_video_reversed.mp4
```

Replace `input_video.mp4` with the name of the input video file you want to reverse, and `output_video_reversed.mp4` with the desired name for the reversed output video.

This command will:

-	Take the input video specified with `-i`.
-	Apply the `reverse` video filter with `-vf "reverse"`, which reverses the video stream.
-	Apply the `areverse` audio filter with `-af "areverse"`, which reverses the audio stream.
-	Save the reversed video and audio as a new file named `output_video_reversed.mp4`.
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