Green bar under picture, video flux acquiring

[Marthus]

Hello,

I have an issue with a green bar below the image of a video acquisition.

My problem in detail:
I'm on Linux.
I need to save images from a video flux that reaches the PC via a BNC cable and a Dazzle capture card that allows the translation BNC / USB.
Everything works pretty well. With VideoforLinux2 I can capture my video flux, then through screenshots, I can take the pictures I want.

The trouble is a green block below the video. It remains, of course, when I capture my pictures.
Until now I post-cut images with The Gimp (or Xnview), but I am not the only one to use the equipment and it would be preferable that images do not have this green band.

I saw a couple of options:
- Find a way to trim and properly center the acquisition to exclude the green band, so I could then capture the wall images already centered without the green band.
- Or make the screenshot clip that part of the picture.

So I first tried to trim the video flux, but as soon as I touched it, I could not gain the flux anymore.
I then tried to crop the video display, to then take the catch. But have not succeeded.
I tried trimming options (3:4 -> 16, 9 ... etc.) But the trouble is that it cuts both above and below, and that I only want the bottom to be removed.
I then looked into the advanced options of VLC to crop during the image capture and lost myself somewhere between capture options and display ones.

Last attempt: I came to that forum I searched a bit and finally registered to ask for your help.

I can't put the pictures in question, but here is a diagram:


Thanks

Marthus

[Jean-Baptiste Kempf]

Why don't you just cut the bottom pixels?

[Marthus]

How? I do it with The Gimp but it is after taking the picture from VLC. And it takes a lot of time (I take several pictures at once) I do also with Xnview to crop all the pictures at once, but it is a bit complicated (I am not the only one to use it so it would be preferable that the pictures don't have the green bar after been captured to limit errors.)

Is there an option in VLC to cut the bottom pixels before or while capturing images?

[Jean-Baptiste Kempf]

Yes, VLC can cut the bottom pixel.

[Marthus]

...

How?

[Jean-Baptiste Kempf]

Using the crop filter?

[Marthus]

Bon, parlons français, ça sera aussi simple.

En fait le truc c'est que j'ai déjà essayé de plusieurs façons, comme je le disais dans mon pavé, et je n'y suis pas parvenu. Je dois probablement être manchot, mais je n'ai pas été foutu de trouver une doc qui explique comment s'y prendre convenablement. J'ai modifié des paramètres dans un peu tous les coins pour tester, mais je n'en ai pas trouvé qui agisse tel que je le voudrais.

Donc serait-il possible de me dire quels paramètres sont à modifier exactement? Il faudrait pouvoir virer 90 pixels en bas de l'image avant de prendre la capture d'image.

Merci pour l'aide

........................

English: Already tried several times! Could I get the paramaters to modify in order to remove 90pixels at the bottom of the video before to take the snapshot (or a tutorial which explains that) please?

[Jean-Baptiste Kempf]

Menu->Effets->Crop->Bas: 90px

[Marthus]

Ok, it works for the video (I looked in the wrong section)

So it cuts the video frame, but when I snapshot, the green bar comes back. So it didn't solve my problem

I tried to crop the frame, and save a snapshot (I then closed and the setting disappeared) The green bar was on the snapshot.
I tried to crop the frame and go in tool->preferences->Video->filter module video output->select "crop"
but after saving and restarting, the green bar reappeared on the video frame (and of course, on the snapshot)

Any way to keep the crop for the snapshot?

Thanks for help

[Mon anglais n'étant pas toujours parfait, hélas:
Je regardais dans la mauvaise section, j'étais dans les filtres vidéo dans "Préférences"...
Du coup en passant par "effets" on peut effectivement rogner la vidéo, mais ce rognage ne reste pas pour le snapshot.
Y a-t-il une option pour que le snapshot prenne en compte le rognage?

Merci beaucoup en tous cas!]

[MJARA]

Hi All,

I understand that the green bar problem was skipped out cropping the video, but the problem of the green bar...??? How to solve it? or why it is generated?

I am on Win7-64bit, VLC_Player 1.1.11, and I am trying to make a wall of 4x1. The video is 5120x720 (4 720p screens) and when I split it using the wall filter there appears the green strap at the bottom of the video...how to really solve it? I need that the video play OK.

Any help will be appreciated!

Thanks for reading,

MJ