Video Thumbnails

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Hotdog

Video Thumbnails

Post by Hotdog »

I am trying to figure out how XnView determines what part of a movie file (mpg; wmv etc.) to take the thumbnail image from. It doesn't seem to use the first image of the movie. Any thoughts on this?
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Re: Video Thumbnails

Post by xnview »

Hotdog wrote:I am trying to figure out how XnView determines what part of a movie file (mpg; wmv etc.) to take the thumbnail image from. It doesn't seem to use the first image of the movie. Any thoughts on this?
I extract frame at 10%
Pierre.
Hotdog

video thumbnails

Post by Hotdog »

OK - thanks
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Re: Video Thumbnails

Post by David.P »

xnview wrote:I extract frame at 10%
Hi Pierre,

I was wondering whether there is a possibility to change that video frame extraction point -- or is it hard-coded into the program, at the moment?

What I'm trying to do is display masses (thousands) of short video clips from a surveillance camera where in each video a moving object is recorded. However, the movement happens mostly at about 2 seconds after the video starts (video length is typically 3 to 5 seconds).

At the moment, xnview shows only the static picture BEFORE something is happening for most video clips, and therefore I can not distinguish between the events of the different video clips because almost all thumbnails look the same -- see screenshot below.

Do you think there is a way to maybe have a setting where you can specify "extract video thumbnail at x seconds / at x percent of video duration"?

Image

(Even better, and an absolute killer feature would be something like "extract thumbnail at the peak of motion / at the peak of bitrate inside the video… Well, this one might be somewhat too difficult to implement ;))

Thank you already for a judgement from your point of view, regarding the custom setting for video thumbnail extraction timing,

David.P
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Re: Video Thumbnails

Post by xnview »

David.P wrote: Do you think there is a way to maybe have a setting where you can specify "extract video thumbnail at x seconds / at x percent of video duration"?
Ok, i'll add it
Pierre.
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Post by David.P »

WOW Pierre, that was fast...!

I'm already very much looking forward to this feature -- another "Worlds First" for XnView!

Cheers,
David.P
matt1696
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Re: Video Thumbnails

Post by matt1696 »

xnview wrote:
David.P wrote: Do you think there is a way to maybe have a setting where you can specify "extract video thumbnail at x seconds / at x percent of video duration"?
Ok, i'll add it
Hi,

Was this feature added in 1.91.6? If so, where can I find the config?

It would be nice to able to use the "Extract Movie Frames" feature in the Tools menu to save custom thumbnails to the cache. Is this possible?

Thanks for the great software - easily the best of it's kind that I've used.

Matt
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Clo
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Similar request

Post by Clo »

:arrow: matt1696

:) Hello !

• A similar request had been posted HERE four months ago, for which I drew a mock-up…

:mrgreen: Kind regards,
Claude
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Post by Guest »

Thanks for the reply Clo... I'm not sure that what I'm asking for is exactly the same as your request.

What I'm asking for is to be able to use a specific custom thumbnail for video files in the browse view.

When the thumbnails are automatically generated, sometimes they are just a black screen or something else inappropriate that doesn't identify the film. This can happen even if "Show First Frame For Videos" is switched off.

I would like to be able to optionally choose custom thumbnails for my video files. Even better, I'd like to be able to use the "Extract Movie Frames" feature in the Tools menu to be able to create that thumbnail and replace the existing one.

So my ideal method would be...

1. Identify a movie file with an inappropriate thumbnail

2. Select the file and choose Tools / Extract Movie Frames

3. Select the frame I want to use for the thumbnail and click a button that replaces the existing useless thumbnail with the one of my choosing.

Does that make sense? Sorry if I wasn't clear or if I misunderstand. Or perhaps there is a way of doing this that I am unaware of?

Matt
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Post by matt1696 »

Sorry, the post above is me.. I didn't realised I wasn't logged in ;)
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An internal command…

Post by Clo »

—> matt1696

:) Good evening,
1. … 2. … (OK)
3. Select the frame I want to use for the thumbnail and click a button that replaces the existing useless thumbnail with the one of my choosing.
• Well, I got the issue, and I'm aware that the former suggestion was not exactly that you need…
- However, I quoted it because I'ld like to complete that (fake) dialogue in order you could define the “explicit” image
to extract as the useful current thumb nail…
- The only problem then is :  
¤ How to process¦store that thumb nail temporarily till you ask for display it instead of the standard one?
- Assuming that is solved (I'm very optimistic, still…), then an internal command from a button in the main tool-bar
could replace the crappy thumb nail in the database with the right one…
- Let's say that indeed each new “good” thumb nail might replace the previous one in the temporary storage
- assuming that only one explicit thumb nail is stored there at once.
- On the board of thumb nails, the replaced images might be shown with a special marker (overlay small icon).

EDIT : That it could be for the configuration on the same page than quoted above :

      Image

- Please, notice that the “Gallery” feature could allow to define prior which is the right image as your explicit thumb nail ;)

:mrgreen: KR
Claude
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Last edited by Clo on Thu Dec 06, 2007 7:42 am, edited 1 time in total.
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Mike

video thumbs

Post by Mike »

Great program, love it! Would make a perfect video-manager. Just one thing:
Many more or less exotic formats (mov, but also some asf, wmf) ignore the frame extraction setting (VideoFramePercent) and always extract frame no. 1, that is black in many cases. Seems to be totally codec dependent. I have a mixed collection and about 30% of the thumbs are black only. Transcode all of them is not an option, because of the large file size.
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Post by matt1696 »

You're right... looking at the clips using G-Spot codec identifier, it seems the following types are affected:

MPEG1
MP43

and possibly WMV1, although I can only see one example.

The following codec always produces a thumbnail of a green screen as if it can't be read, even though I can play it using XviD, DivX or Libavcodec in ffdshow :

DX50

I also have a quite a few clips that simply crash the program when trying to extract a thumbnail. These are of many types, so I assume they have some corruption that although I can play them with MPC or VLC, XNview is sensitive to. I usually rename them with a different extension to stop the program trying to extract a thumbnail.

Of course, the feature I requested is needed even where the first frame isn't used, since you can get a meaningless frame anyway....

Matt
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Post by xnview »

matt1696 wrote: I also have a quite a few clips that simply crash the program when trying to extract a thumbnail. These are of many types, so I assume they have some corruption that although I can play them with MPC or VLC, XNview is sensitive to. I usually rename them with a different extension to stop the program trying to extract a thumbnail.
Is it possible to have the movie files?
Pierre.
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Post by matt1696 »

I'll try and find one that's small enough to upload. The one's I've looked at so far either turned out to be MPEG1 or were OK once I isolated them in their own folder (the original crashes happened when processing large amounts of files at once).

There's one that produces a corrupt image, but that uses the MP4S codec, which I'm not surprised causes issues.

I'll see what I can find...
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