Sometimes videos will appear smaller or larger when played with the VLC Media Player, which is a free, cross-platform media player and converter from Videolan.org. The video may appear in full-screen mode, or it may appear squished due to playback in a different aspect ratio. Fixing a specific video's size is a simple process of finding the correct aspect ratio for your video and locking it using VLC's video options.
Visit Videolan.org and click the "Download VLC" icon. Double-click the installation package when download has finished and open the program's contents. Follow the onscreen installation instructions, accept the licensing terms, and open the latest version of VLC Media Player.
Go to VLC's "Preferences" screen and click the "Video" tab. Make sure the "Enable Video" box is checked in the top-left corner of the screen. Disable the Full-screen box so the check mark disappears.
Click the "Output Module" drop-down box and choose "Default." Click "Save" to disable automatic full-screen playback and save your changes.
Open your video in VLC Media Player. Click the "Video" tab at the top of the screen and scroll down to "Aspect-Ratio." If your video looks fine, click the "Lock Aspect Ratio" option.
Select one of the aspect-ratio options if your video is squished, generally "4:3" or "16:9" for most videos. Try the "Default" option, if not selected, and VLC will choose one automatically.
Click the "Lock Aspect Ratio" button in the "Aspect-Ratio" sub-menu.
Most videos are either in a "4:3" (full-screen) or "16:9" (widescreen) aspect ratio. "16:9" videos have black bars at the top and bottom of your video.