Depth needs two things: a file that carries two views, and a device told to send one to each eye. Both fail in ways that look the same on the sofa, and they are fixed in different places. Answer four questions and you will know which one you have.
1. The player is showing the file flat. If you can see two nearly identical halves side by side, the file is fine — it is carrying both views. The player is drawing the whole frame as one image, so each eye receives the entire pair. This is the most common report and the least mysterious: it is a setting, not a defect.
2. The glasses are mirroring. Mirror mode sends the same picture to both panels. It is indistinguishable from side-by-side in the operating system's display settings — both are just a wide monitor — which is exactly why it needs to be read from the device. The device check does that and prints the mode code it found.
3. The two views are misaligned. Ghosted edges come from a vertical offset or a small rotation baked into the pair. It is measurable: shift one half by a few pixels until the difference is smallest, and the size of that shift is the defect. The converter measures it and can remove it.
4. The eyes are swapped. Depth that feels inside-out — the scene bending away instead of toward you — is the signature. Nothing is broken; the halves are simply going to the wrong eyes.
5. The headset player is in 2D mode. Standalone players open in flat-screen mode by default and stay there until told otherwise. If it never learns that the file is stereo, the headset has nothing to split.
None of these upload anything; the file and the device stay on your machine.
DepthSnap — free browser-based 2D to 3D SBS converter. No upload, no signup, no watermark.