DepthSnap / Device guides / Playback fixes
Troubleshooting · Free

SBS 3D won't play?

Black screen, two flat pictures, stretched or doubled — six causes in the order they actually happen, and where the right switch hides on Quest, Pico, Vision Pro, XREAL and VITURE.

Check 6 causesDevices Quest · Pico · Vision Pro · glassesCost FreeUpload None

First: is the file actually SBS?

Pause on any frame. You should see two nearly identical pictures side by side — that is SBS. One picture only = not a stereo file at all. Two very different pictures = the eyes are swapped. This one-second check removes most of the guesswork.

Six causes, in the order they happen

The player is still in 2D mode

By far the most common. A side-by-side file keeps both eyes in one frame, so 2D playback shows two squeezed copies. Nothing is wrong with the file.

Half-SBS and Full-SBS got mixed up

A half-SBS file forced into full-width mode looks stretched fat; a full-SBS file treated as half looks skinny. Match the mode to the file — half vs full, explained.

The eyes are swapped

Depth looks inverted — near objects feel far away, and long viewing hurts. Every player has an L/R swap or reverse-stereo toggle; flip it once.

On glasses: the IPD dial is wrong

XREAL, VITURE and Rokid are displays, not computers — the picture is doubled or soft until the physical IPD (and on VITURE, the myopia dials) match your eyes.

It won't open at all — black screen

Usually the format inside the file, not the file itself: several headset players only play the most common mp4 variant. Re-export in the standard profile mp4, or try a player that handles HEVC/AV1.

Only one half shows, or the picture is cropped

The player opened it as a normal video and cropped to the left eye. Switch it to SBS / 左右 first, then set screen size — a very large virtual screen can also crop the edges.

Where the switch is, per device

DeviceWhat to selectNotes
Meta Quest 2 / 3 / 3S / ProSBS · Left-Right (3D)Skybox and DeoVR usually auto-detect; 4XVR and Pigasus need it once per file. The built-in Files gallery has no SBS switch at all.
Pico 4 / 4 Pro / 4 Ultra左右The built-in Pico Video calls the format 左右 — open the clip, then switch the format. Skybox reads the tag; 4XVR asks once.
Apple Vision ProSBS mode in a third-party playervisionOS has no system-wide SBS switch and Files plays the mp4 as a flat wide video. You need a player with an SBS mode.
XREAL Air / UltraSBS in Nebula or BeamChoose SBS, set screen size, then judge depth. On a PC, VLC and mpv read the 3D tag.
VITURE Pro / LiteSBS / 左右 in SpaceWalkerSelect SBS, then adjust IPD and the myopia dials before judging depth.

FAQ

My file plays as two flat pictures side by side. Is the file broken?
No. That is exactly what a side-by-side file looks like when the player is in 2D mode — both eyes are stored in one frame. Turn on SBS / 左右 / 3D / Left-Right in the player and it collapses into one 3D picture.
Why is my finished file 3840×1080 instead of 1920×1080?
SBS doubles the width on purpose: Full-SBS with 1080p per eye is 3840×1080, and top-bottom doubles the height instead (1920×2160). The player squeezes it back and expands each eye.
Quest's own gallery shows it as a flat wide video. Why?
The built-in Files gallery has no SBS switch — it is not a 3D player. Use Skybox, DeoVR, 4XVR or Pigasus, which do.
Half-SBS or Full-SBS — which should I pick?
Half-SBS halves the width per eye to keep files small (good for streaming and phones); Full-SBS keeps full per-eye resolution and is worth it on Quest 3 / 3S pancake optics and desktop VR.
The depth looks inverted — near things feel far away.
The eyes are swapped. Find the L/R swap, reverse stereo or "swap eyes" option in the player and toggle it. Converters can also export crossed-eye output if a player has no such switch.
Glasses: the picture is doubled or blurry, but the file is fine elsewhere.
That is the IPD. XREAL, VITURE and Rokid have a physical dial — set it to your interpupillary distance; on VITURE, also dial in the myopia adjustment. The file is not the problem.
It won't open at all — just a black screen.
Most often the format inside: several headset players only play the most common mp4 variant. Re-export in the standard profile mp4. This site prefers H.264 mp4 for exactly that reason.

If the file simply has no depth, no player can invent it — that is the one case that needs a conversion.

Convert a photo or a clip — free