MediaCoder

Hi folks. Can MediaCoder do this, or do you otherwise know a program that can do the following:

parse a video file, detect all scene changes and make snapshots of frame 1 of each new scene

This way you create a "storyboard"/"snapsh gallery" for the movie.
Thank you.

Hi. Thanks for the reply. I'm not sure if I understood your point about erotic stuff, but I'm happy that you like the idea. If you google "video summarization" or "scene change detection" there are like 1 million results. And the weird thing about it is that there are literally hundreds of scholarly papers on the topic, but there doesn't seem to be a single implementation. Not that I found at least, and I have been searching for almost 2 hours.

The trigger was that one of these days I wanted to find a specific important scene in a 2:30 hour movie but I couldn't remember where it was. The scene's duration was just about 10 seconds and I spent about 15-30 minutes looking for it and then gave up.

And I often want to take screenshots of pictures in documentaries before I delete the film and takes quite a while to fastforward the film in x8 speed and even then you could still miss images that you wanted to snapshot.

It also gives you a quick overview of a film ...

Anyway, I think you see the bigger picture.

If anyone ever hears about a program that would be able to do this, then please let me know here! Many thanks.
I'm sure there must be something. Given that the issue is already figured out theoretically and the algorithms are freely available, I don't think it's possible, that no program has ever implemented it.

Tools to make thumbnail storyboard (but not based on scenechange)
On KMPlayer: Right-click menu -> Capture -> Make Storyboard
FFmpeg: http://stream0.org/2008/02/howto-extrac ... -a-vi.html ( search for 'board')

Ways to see just the I-frames of a video:
With VLC, select to skip P and B frames then fast-forward at 16x or 32x if you like. [1]
Open the video in VirtualDub or Avidemux and seek only by keyframes [2]


[1] Tools / Preferences (Show settings: All) / Input/Codecs / other codecs / FFmpeg / Skip frame :3
[2] VDub: shift+arrow keys left/right . AviDemux: the 'fast forward' looking buttons on the left of A B.

Recently i saw a documentary for the le-mans (1958 ?) car crash. Where the car was hit by another. Then after took off and exploded through the spectator stadium. The photos originaly from old film, was made to a video so could be shown what happened in real time.

Try mediacoder with.

Video: Encoder - Frame Dumper

Audio: Disabled

Container: MJPEG (or maybe even default)

thank you so much for all your comments and your help!

@AnonCrow: thanks, your information was very valuable. It's still not entirely what I was looking for, but at any rate a big step forward for me. Problem is that depending on the codec, I frames happen much more often than scene changes, all the more so for longer scenes and for inefficient codecs. Also, I would like to use the exported scene change frames to identify added and deleted scenes when compare two videos. If the FPS frame rate is slightly different, the exported I-frames wouldn't match, but the scene change frames still would.

@encroder: you too, many thanks! I couldn't get it to work, but I am still trying combinations of settings. But ... wouldn't this dump ALL frames ? (as opposed to scene change frames or I-frames only) ? Is there a setting in Mediacoder which would help me achieve this? Again, many thanks.

I just happened on this topic.
It is only a partial answer, but some Video Editors do scene-change detect.
For example, when importing a file into Windows Movie Maker 2.6 (described in the Guide on Video Editors at viewtopic.php?f=17&t=11406), it displays the file as many sub-files, each seems to be a new scene. Unfortunately, I don't think it has a Snapshot button (frame capture) as did the older version of Movie Maker ??!

Of course, you may need to convert the source file to a format that suits this App.

As a check, I just re-installed Windows Movie Maker 2.6 and, lo and behold, it has a "Take Picture" button at the right on the Preview panel, which takes JPG images into your chosen folder.
Hence, select each scene in the Collection panel, which opens it in the Preview, at the first frame, and hit the button!