Between two LCD screens of a video wall there is always a strip of plastic or metal: the bezel. Even on dedicated video wall panels it measures a few millimetres. Bezel compensation decides what happens to the part of the image that falls on that strip. Get it right and a straight line crossing the wall stays straight. Get it wrong and every diagonal looks broken at the seams.
Two ways to handle bezels
With compensation: the window effect
The image is laid out as if the bezels were part of the wall, and the pixels behind them are simply not shown. It looks like looking through a window with mullions: objects moving across screens stay aligned and diagonals continue correctly. This is the right choice for footage, panoramas, motion graphics and anything with lines that cross screens.
Without compensation: nothing hidden
Every pixel of the source is shown, and the screens sit edge to edge in the image. Nothing is lost behind the frames, but crossing lines get a small offset at each seam. It is the safer choice for text, tables or interfaces where losing a few pixels near an edge would cut a letter, and for LED walls, which have no bezels.
Measure your bezels in pixels
You need the gap between the visible image areas of two neighbouring screens, converted to pixels.
- Find the gap in millimetres. Add the right bezel of one screen to the left bezel of the next, plus any mounting gap. Datasheets for video wall panels usually give it directly as the “bezel to bezel” value.
- Find the pixel density. Divide the horizontal resolution by the width of the active area, also in the datasheet. A typical 55″ Full HD panel has an active area 1209.6 mm wide: 1920 ÷ 1209.6 = 1.59 pixels per millimetre.
- Multiply. Gap in mm × pixels per mm = bezel in pixels. Round to the nearest whole pixel.
| Screens (55″ Full HD) | Bezel to bezel | Bezel in pixels |
|---|---|---|
| Ultra-narrow video wall panel | 0.9 mm | 1 px |
| Narrow video wall panel | 3.5 mm | 6 px |
| Professional display | 12 mm | 19 px |
| Consumer TV | 20 mm | 32 px |
Do the same vertically with the vertical resolution and the active area height if your wall has several rows. On most panels pixels are square, so the value is the same.
Size the source for compensation
With compensation, the source must include the hidden pixels. For a 4 × 1 wall of Full HD screens with 6 px bezels, the full canvas is 4 × 1920 + 3 × 6 = 7698 × 1080. Designed at that size, each tile comes out at exactly 1920 × 1080.
If your video is already 7680 × 1080, compensation leaves 7680 − 18 = 7662 px for the four screens: tiles of 1915 px, with 2 px left over. You can scale each tile back to 1920 × 1080 (a 0.3% horizontal stretch nobody will notice), or ask the designer for a 7698 px version.
Bezel compensation in WallSplitter
WallSplitter has two settings, bezel between columns and bezel between rows, in pixels. The preview shows the hidden strips in red so you can check them before exporting, and the resize option brings every tile back to your screens' native resolution in the same pass. Learn more about the whole workflow in how to split a video for a video wall.
Common mistakes
- Measuring only one bezel instead of the gap between two images.
- Using the outer dimensions of the screen instead of the active area to compute pixel density.
- Compensating on an LED wall: cabinets are seamless, keep the value at zero.
- Putting text right on a seam: even compensated, a letter split across two screens is hard to read.