How To Automate Video Hide Grabs Using Ffmpeg

Part 1 of this 2-part serial explains how to role VLC, a GUI-based video player, to capture unmarried all the same frames from a video file. If you lot are taking many snapshots, you lot may detect the manual VLC method besides laborious. This post service shows how to automate the capture procedure using ffmpeg, a command-line tool.

Extract frame at a given instant

The starting fourth dimension scenario is to only stimulate got a unmarried snapshot at a given fourth dimension instant.

 $ ffmpeg -i P5080821.MP4 -vframes 1 -ss 00:01:39 $(date +%Y%m%d-%H%M%S).png 

Notes:

• -i

  P5080821.MP4 is the input video file.

• -vframes

  The let on of frames or snapshots to capture is 1.

• -ss

  Skip ahead the input video for the given fourth dimension interval from the commence of the video. The fourth dimension interval tin live on specified inward the let on of seconds, or inward the "hh:mm:ss[.xxx]" format. The higher upward instance takes a snapshot at 1 infinitesimal 39 seconds from the start.

• PNG file cite

  The cite of the output file contains the file creation timestamp formatted using the date command.

Auto extract multiple frames

Suppose you lot desire to extract a serial of frames taken at a regular fourth dimension interval starting from a specific fourth dimension instant. The next instance extracts i frame per 2d starting at 1 infinitesimal 39 seconds into the video.

 $ ffmpeg -i P5080821.MP4 -r 1 -ss 00:01:39  example-%03d.png 

Notes:

• -r

  This is the frame charge per unit of measurement per 2d (e.g., 1 per second).

• %03d

  The output files are sequentially numbered starting at 001. Output files from the higher upward instance volition live on named example-001.png, example-002.png, example-003.png, etc.

If the video is long, you lot may cease upward amongst besides many pictures. You may restrain the let on of frames past times specifying the absolute let on of frames (-vframes) to extract or the absolute fourth dimension duration (-t).

 $ ffmpeg -i P5080823.MP4 -r 1 -ss 00:01:39 -t 00:02:00 example-%03d.png 

In the higher upward example, snapshots are taken at a charge per unit of measurement of 1 frame per second, starting at 1 infinitesimal 39 seconds into the video, in addition to alone for a duration of ii minutes.

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