The easiest way to watch 3D stereoscopic video using VLC:

Go to Tools –> Effects and filters (or Ctrl+E)

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Choose the Video Effects –> Crop tab

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Crop from left or right exactly half of your full video resolution (usually 960 pixels)
Close the effects dialog
Change the aspect ration to 32:9 and there you go
(If you don’t have a 32:9 aspect ration it can be manually added using advanced settings like below)

 

Open VLC, and go to Tools > Preferences.
1. Choose Show settings > All.
2. From the left pane, scroll down to the bottom and click Video.
3. From the right pane, scroll down to Source aspect ratio; fill in 32:9.
4. Hit Save

The next time you open VLC, your videos will automatically have your chosen aspect ratio

 

 

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