0

I'm extracting still frames from a video using the basic code: 

ffmpeg -i video.MXF -vf fps=1 output_%04d.png

In some videos, this yields images that, when the camera was moving, look much blurrier than when watching the video (see example below). The still frames from when the camera was not moving look sharper (closer to how it looks in video playback).

The video specs are: mpeg2video, yuv422p, 1280x720 (according to FFprobe).

Is this inherent within the video coding or structure? The video looks so nice when in motion, but even when I pause in VLC the frame goes from sharp to blurred.

Are there any additions to my FFmpeg code that could result in sharper images? I tried adding a yadif filter, but it made no difference (the video isn't interlaced anyways).

Unfortunately I can't post a video sample online, but below is an example of a sharper image and a blurry image; both look in focus during video playback and are about a second apart in the video (that's the same orange sea star on the left side).

Sharper image Blurrier image

Evan
  • 1,960
  • 4
  • 26
  • 54
  • 1
    The screenshots remind me of a job involving thousands of underwater biological/geological research videos from the submersible "Delta". Most were fairly typical, but occasionally something interesting would show up like an octopus or...a milk cow. – llogan Jan 24 '17 at 02:51
  • As for the blurriness there likely isn't much you can do: it's a trick of the eyes, your brain fills in the details, but you could provide a short sample so we can take a look in case there may be something else going on. – llogan Jan 24 '17 at 02:59
  • That's what I suspected was happening. Interesting that a bunch of blurry frames can combine to make a sharp looking video. – Evan Jan 24 '17 at 18:01

1 Answers1

1

Blurriness is either due to motion of the camera or motion of the object being captured. This is common especially when the video is captured at lower FPS. Check if you have the video source captured at higher FPS which might get you sharper images. As far as the current video and corresponding snapshots, nothing much can be done about it since that is the way those frames are captured.

prashanthns
  • 339
  • 2
  • 12