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Never did I think I would ever see anything close to related to A$AP on HN. I love this place.
Hah, for the past day, I've been trying to somehow submit the Helicopter music video / album as a whole to HN. Glad someone figured out the angle was Gaussian.
And nearly a Carti post at the top of HN
yeah that had me do a double take lol
I run a programming company and one of my sales people was surprised to see I liked soundcloud rap. I was like:

What did you expect?

>Classical music?

Nah I like hype, helps when things are slow.

I know right? I'm into both things tech and hip hop, didn't expect them to collide
Be sure to watch the video itself* - it’s really a great piece of work. The energy is frenetic and it’s got this beautiful balance of surrealism from the effects and groundedness from the human performances.

* (Mute it if you don’t like the music, just like the rest of us will if you complain about the music)

Similarly, the music video for Taylor Swif[0] (another track by A$AP Rocky) is just as surrealistic and weird in the best way possible, but with an eastern european flavor of it (which is obviously intentional and makes sense, given the filming location and being very on-the-nose with the theme).

0. https://youtu.be/5URefVYaJrA

Watch the video to the very end: the final splat is not a gaussian one.
so basically despite the higher resource requirements like 10TB of data for 30 minutes of footage, the compositing is so much faster and more flexible and those resources can be deleted or moved to long term storage in the cloud very quickly and the project can move on

fascinating

I wouldn't have normally read this and watched the video, but my Claude sessions were already executing a plan

the tl;dr is that all the actors were scanned in a 3D point cloud system and then "NeRF"'d which means to extrapolate any missing data about their transposed 3D model

this was then more easily placed into the video than trying to compose and place 2D actors layer by layer

> and then "NeRF"'d which means to extrapolate any missing data about their transposed 3D model

Not sure if it's you or the original article but that's a slightly misleading summary of NeRFs.

Gaussian splatting is not NeRF (neural radiance field), but it is a type of radiance field, and supports novel view synthesis. The difference is in an explicit point cloud representation (Gaussian splatting), versus a process that needs to be inferred by a neural network.
To be honest it looks like it was rendered in an old version of Unreal Engine. That may be an intentional choice - I wonder how realistic guassian splatting can look? Can you redo lights, shadows, remove or move parts of the scene, while preserving the original fidelity and realism?

The way TV/movie production is going (record 100s of hours of footage from multiple angles and edit it all in post) I wonder if this is the end state. Gaussian splatting for the humans and green screens for the rest?

Yes, they talk about this in the article and that’s exactly what they did.
The aesthetic here is at least partially an intentional choice to lean into the artifacts produced by Gaussian splatting, particularly dynamic (4DGS) splatting. There is temporal inconsistency when capturing performances like this, which are exacerbated by relighting.

That said, the technology is rapidly advancing and this type of volumetric capture is definitely sticking around.

The quality can also be really good, especially for static environments: https://www.linkedin.com/posts/christoph-schindelar-79515351....

Knowing what I know about the artist in this video this was probably more about the novelty of the technology and the creative freedom it offers rather than it is budget.
For me it felt more like higher detail version of Teardown, the voxel-based 3d demolition game. Sure it's splats and not voxels, but the camera and the lighting give this strong voxel game vibe.
We will be able to have imax level 3D technically today if you feed it the correct data
I wonder if you are thinking Source engine? I was getting serious skibidi toilet vibes during several parts of this video.
Really amazing video. Unfortunately this article is like 60% over my head. Regardless, I actually love reading jargon-filled statements like this that are totally normal to the initiated but are completely inscrutable to outsiders.

    "That data was then brought into Houdini, where the post production team used CG Nomads GSOPs for manipulation and sequencing, and OTOY’s OctaneRender for final rendering. Thanks to this combination, the production team was also able to relight the splats."
Hi, I'm one of the creators of GSOPs for SideFX Houdini.

The gist is that Gaussian splats can replicate reality quite effectively with many 3D ellipsoids (stored as a type of point cloud). Houdini is software that excels at manipulating vast numbers of points, and renderers (such as Octane) can now leverage this type of data to integrate with traditional computer graphics primitives, lights, and techniques.

Reminds me of Kurtwood Smith’s piping sales pitch in The Patriot
My bad! I am the author. Gaussian splatting allows you to take a series of normal 2D images or a video and reconstruct very lifelike 3D from it. It’s a type of radiance field, like NeRFs or voxel based methods like Plenoxels!
Super cool to read but can someone eli5 what Gaussian splatting is (and/or radiance fields?) specifically to how the article talks about it finally being "mature enough"? What's changed that this is now possible?
I found this VFX breakdown of the recent Superman movie to have a great explanation of what it is and what it makes possible: https://youtu.be/eyAVWH61R8E?t=232

tl;dr eli5: Instead of capturing spots of color as they would appear to a camera, they capture spots of color and where they exist in the world. By combining multiple cameras doing this, you can make a 3D works from footage that you can then zoom a virtual camera round.

For the ELI5, Gaussian splatting represents the scene as millions of tiny, blurry colored blobs in 3D space and renders by quickly "splatting" them onto the screen, making it much faster than computing an image by querying a neural net model like radiance fields.

I'm not up on how things have changed recently

Gaussian splatting is a way to record 3-dimensional video. You capture a scene from many angles simultaneously and then combine all of those into a single representation. Ideally, that representation is good enough that you can then, post-production, simulate camera angles you didn't originally record.

For example, the camera orbits around the performers in this music video are difficult to imagine in real space. Even if you could pull it off using robotic motion control arms, it would require that the entire choreography is fixed in place before filming. This video clearly takes advantage of being able to direct whatever camera motion the artist wanted in the 3d virtual space of the final composed scene.

To do this, the representation needs to estimate the radiance field, i.e. the amount and color of light visible at every point in your 3d volume, viewed from every angle. It's not possible to do this at high resolution by breaking that space up into voxels, those scale badly, O(n^3). You could attempt to guess at some mesh geometry and paint textures on to it compatible with the camera views, but that's difficult to automate.

Gaussian splatting estimates these radiance fields by assuming that the radiance is build from millions of fuzzy, colored balls positioned, stretched, and rotated in space. These are the Gaussian splats.

Once you have that representation, constructing a novel camera angle is as simple as positioning and angling your virtual camera and then recording the colors and positions of all the splats that are visible.

It turns out that this approach is pretty amenable to techniques similar to modern deep learning. You basically train the positions/shapes/rotations of the splats via gradient descent. It's mostly been explored in research labs but lately production-oriented tools have been built for popular 3d motion graphics tools like Houdini, making it more available.

It’s a point cloud where each point is a semitransparent blob that can have a view dependent color: color changes depending on direction you look at them. Allowing to capture reflections, iridescence…

You generate the point clouds from multiple images of a scene or an object and some machine learning magic

1. Create a point cloud from a scene (either via lidar, or via photogrammetry from multiple images)

2. Replace each point of the point cloud with a fuzzy ellipsoid, that has a bunch of parameters for its position + size + orientation + view-dependent color (via spherical harmonics up to some low order)

3. If you render these ellipsoids using a differentiable renderer, then you can subtract the resulting image from the ground truth (i.e. your original photos), and calculate the partial derivatives of the error with respect to each of the millions of ellipsoid parameters that you fed into the renderer.

4. Now you can run gradient descent using the differentiable renderer, which makes your fuzzy ellipsoids converge to something closely reproducing the ground truth images (from multiple angles).

5. Since the ellipsoids started at the 3D point cloud's positions, the 3D structure of the scene will likely be preserved during gradient descent, thus the resulting scene will support novel camera angles with plausible-looking results.

I assume that the differentiable renderer is only given its position and viewing angle at any one time (in order to be able to generalize to new viewing angles)?

Is it a fully connected NN?

Pretty sure most of this could be filmed with a camera drone and preprogrammed flight path...

Did the Gaussian splatting actually make it any cheaper? Especially considering that it needed 50+ fixed camera angles to splat properly, and extensive post-processing work both computationally and human labour, a camera drone just seems easier.

Flying a camera drone with such proximity and acceleration would be a safety nightmare.
If it was achievable, cheaper, and of equal quality then it would have been done that way. Surely it would’ve been done that way a long time ago too. Drone paths have been around a lot longer than this technology.

There’s no proof of your claim and this video is proof of the opposite.

I think you’re missing the point

Volumetric capture like this allows you to decide on the camera angles in post-production

A drone path would not allow for such seamless transitions, never mind the planning required to nail all that choreography, effects, etc.

This approach is 100% flexible, and I'm sure at least part of the magic came from the process of play and experimentation in post.

> Pretty sure most of this could be filmed with a camera drone and preprogrammed flight path

This is a “Dropbox is just ftp and rsync” level comment. There’s a shot in there where Rocky is sitting on top of the spinning blades of a helicopter and the camera smoothly transitions from flying around the room to solidly rotating along with the blades, so it’s fixed relative to rocky. Not only would programming a camera drone to follow this path be extremely difficult (and wouldn’t look as good), but just setting up the stunt would be cost prohibitive.

This is just one example of the hundreds you could come up with.

This might be the first time I'm stumbling on Dunning Kruger on HN, no offense.
Can somebody explain to me what was actually scanned? Only the actors doing movements like push ups, or whole scenes / rooms?
How did Rhianna look him in the eyes and say "yes babe, good album, release it, this is what the people wanted after 7 years, it is pleasing to listen to and enjoyable"?
> One recurring reaction to the video has been confusion. Viewers assume the imagery is AI-generated. According to Evercoast, that couldn’t be further from the truth. Every stunt, every swing, every fall was physically performed and captured in real space. What makes it feel synthetic is the freedom volumetric capture affords.

No, it’s simply the framerate.

In another setting, it looks like ass, but lo-fi, glitchy shit is perfectly compatible with hip-hop aesthetic. Good track though.
Hi,

I'm David Rhodes, Co-founder of CG Nomads, developer of GSOPs (Gaussian Splatting Operators) for SideFX Houdini. GSOPs was used in combination with OTOY OctaneRender to produce this music video.

If you're interested in the technology and its capabilities, learn more at https://www.cgnomads.com/ or AMA.

Try GSOPs yourself: https://github.com/cgnomads/GSOPs (example content included).

This reminds me about how Soulja Boy just used a cracked copy of Fruity Loops and a cheap microphone and recorded all his songs that made him millions.[1] Edit: Ok this was a big team of VFX producers who did this. Still, prices are coming down dramatically in general, but yeah that idea is a bit of an underfit to this case.

[1] https://www.youtube.com/watch?v=f1rjhVe59ek

Dang, it's been cool watching gaussian splats go from tech demo to real workflow.
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"The team also used Blender heavily for layout and previs, converting splat sequences into lightweight proxy caches for scene planning."
Both of my worlds are colliding with this article. I love reading about how deeply technical products/artifacts get used in art.
aren't music videos supposed to have music?
A$AP Rocky’s music videos has been always great.
Too bad, but I managed to watch about 30 seconds of the video before getting motion sickness.

Seems like a really cool technology, though.

I wonder if anyone else got the same response, or it's just me.

Tangential, but I've been exploring gaussian splatting as a photographic/artistic medium for a while, and love the expressionistic quality of the model output when deprived of data.

https://bayardrandel.com/gaussographs/

A very cool aesthetic and application of technology, thank you for sharing.
They really said it’s capturing everything when A$AP Rocky’s Gaussian splatted mouth in that video be looking worse than AI generated video lol
The end result is really interesting. As others have pointed out, it looks sort of like it was rendered by an early 2000s game engine. There’s a cohesiveness to the art direction that you just can’t get from green screens and the like. In service of some of the worst music made by human brains, but still really cool tech.