Multi Splat is a free browser-based tool from Captures Studio for viewing several Gaussian splat captures together. It aligns captures of the same place onto one coordinate frame, compares them side by side, and plays them in sequence as a 4D timelapse you can render to video. Nothing is installed and no account is required.

How do I align two Gaussian splats?

Open both captures in Align mode, then click the same physical feature on each one — a corner, a fixture, a doorway — to place a matched pair of control points. Three matched pairs are the minimum; more pairs, spread widely across the scene, give a tighter fit. Press Align and Multi Splat solves for the rotation, translation and uniform scale that best brings the second capture onto the first.

Can I compare two Gaussian splat captures side by side?

Yes. Compare mode draws two captures either side of a seam you drag across the viewport, with both halves sharing a single camera so the two views can never drift apart. It is the quickest way to read what changed between two scans of the same place.

What is a 4D timelapse?

A 4D timelapse is a walkthrough of one place across time: instead of a fixed camera watching a scene change, you move freely through a 3D reconstruction while it advances from one capture date to the next. Multi Splat builds one from a set of aligned captures, hands over between them with a cross-fade or a magic wavefront transition, and can render the whole pass to a video file.

Which splat file formats can I load?

Multi Splat opens .ply, .spz, .splat and .ksplat files, plus Spark .rad files, which stream progressively so a large capture is drawable before it has finished arriving. You can drag files straight onto the page or point the tool at a URL.

Are my splat files uploaded to a server?

No. Files you drop in are read and decoded in your own browser and never leave your machine. Because of that, a share link can only carry captures that already live at a URL — a session built from local files can be worked on and exported, but not shared as a link.

Can I share a multi splat with someone else?

Yes. The whole session — every capture, its alignment, your timelapse settings and the tab you are on — is encoded into the page URL, so sharing is just copying the link. You choose whether the recipient gets an editable copy or a view-only one limited to Compare and Timelapse.

Can I export the aligned captures?

Yes. Once captures are aligned you can write them back out as .spz files with their new pose baked in, so the alignment carries into whatever you open them in next. Streaming .rad captures are the one exception and cannot be re-written.

Multi Splat — align, compare and create 4D timelapse of Gaussian splat captures

Multi Splat is a free browser tool for working with more than one Gaussian splat at a time. Load two or more captures of the same place, align them onto a shared coordinate frame by matching points, inspect the difference through a split-screen seam, then play the captures in order as a 4D timelapse and render it to video. Your files are read locally in the browser and are never uploaded.

Modes

Align

Place matching control points on two captures — three pairs is enough — and solve for the position, rotation and scale that brings the second capture onto the first. Points can be nudged, re-placed or deleted, and every edit is undoable.

Compare

Put two aligned captures either side of a draggable seam and sweep it across the scene to read the difference between them, from one shared camera.

4D Timelapse

Play the whole set in capture order as one continuous scrub. Choose a cross-fade or a magic wavefront transition, set the pace per segment, optionally orbit the scene, and render the pass to an MP4 or WebM video with the capture name burned into the frame.

How to align two Gaussian splat captures

Drag two or more splat captures of the same place onto the page, or add them by URL.
In Align mode, pick which capture is the reference and which one is being moved.
Click the same physical feature on both captures to place a matched pair of control points.
Repeat until at least three pairs are placed, spread widely across the scene.
Press Align to solve for the transform that brings the second capture onto the first.
Check the fit in Compare mode, then export the result or play it as a 4D timelapse.

Frequently asked questions

What is Multi Splat?: Multi Splat is a free browser-based tool from Captures Studio for viewing several Gaussian splat captures together. It aligns captures of the same place onto one coordinate frame, compares them side by side, and plays them in sequence as a 4D timelapse you can render to video. Nothing is installed and no account is required.
How do I align two Gaussian splats?: Open both captures in Align mode, then click the same physical feature on each one — a corner, a fixture, a doorway — to place a matched pair of control points. Three matched pairs are the minimum; more pairs, spread widely across the scene, give a tighter fit. Press Align and Multi Splat solves for the rotation, translation and uniform scale that best brings the second capture onto the first.
Can I compare two Gaussian splat captures side by side?: Yes. Compare mode draws two captures either side of a seam you drag across the viewport, with both halves sharing a single camera so the two views can never drift apart. It is the quickest way to read what changed between two scans of the same place.
What is a 4D timelapse?: A 4D timelapse is a walkthrough of one place across time: instead of a fixed camera watching a scene change, you move freely through a 3D reconstruction while it advances from one capture date to the next. Multi Splat builds one from a set of aligned captures, hands over between them with a cross-fade or a magic wavefront transition, and can render the whole pass to a video file.
Which splat file formats can I load?: Multi Splat opens .ply, .spz, .splat and .ksplat files, plus Spark .rad files, which stream progressively so a large capture is drawable before it has finished arriving. You can drag files straight onto the page or point the tool at a URL.
Are my splat files uploaded to a server?: No. Files you drop in are read and decoded in your own browser and never leave your machine. Because of that, a share link can only carry captures that already live at a URL — a session built from local files can be worked on and exported, but not shared as a link.
Can I share a multi splat with someone else?: Yes. The whole session — every capture, its alignment, your timelapse settings and the tab you are on — is encoded into the page URL, so sharing is just copying the link. You choose whether the recipient gets an editable copy or a view-only one limited to Compare and Timelapse.
Can I export the aligned captures?: Yes. Once captures are aligned you can write them back out as .spz files with their new pose baked in, so the alignment carries into whatever you open them in next. Streaming .rad captures are the one exception and cannot be re-written.

Opening Multi Splat…

📁 Drag files here