Will add condensed version here in half an hour.
Prompted by this comment
https://news.ycombinator.com/item?id=44366753
I tried to geolocate the camera.
I uploaded a screenshot from
https://walzr.com/weather-watching
to ChatGPT and it said a lot of things but concluded with “New York City street corner in the East Village”.[1]
I find it utterly amazing that you can throw a random low-quality image at an LLM and it does not only pinpoint the city but also the quarter.
Good, but how to proceed from there? ChatGPT knows how street corners in the East Village look in general, but it does not know every building and every corner. Moreover, it has no access to Google Street View to help find a matching building. So this is kind of a dead end when we want a precise location.
How would a human approach this? From the image it is immediately clear that we have a T-shaped intersection. From the shadows we can conclude that the stem of the T runs east-west and the bar north-south. We see that the stem is a one-way street with cars going only from west to east. This immediately excludes all odd-numbered streets. There are buildings all around and no parks or water.
There are not many intersections in New York that fulfill all these criteria, but what if the area to search was much bigger? Could an LLM do that for us?
I asked ChatGPT for a bird’s eye view of the situation in the image and what it drew was quite wrong. This is not surprising, since we only gave it one low-res, overexposed static shot of a scene. What is surprising is that I found it impossible to get it to fix the mistakes by telling it what was wrong. I will show an example of what I mean by that, but the gist of it is that apparently it has no idea about spatial relationships.
Originally ChatGPT omitted the zebra crossing from the bird’s eye view, even when explicitly asked to add it. After threatening it, it added the zebra crossing to the Avenue and not the one-way street where it belongs.
I: “No, the zebra is in the wrong direction. It is across the horizontal street.”
ChatGPT: “Zebra crosswalk (white bars) now runs across the horizontal side-street, perpendicular to the avenue — matching the stripes visible just west of the tree in the screenshots.” [2]
In the image it created, the zebra is within a building now, so I gave up on high-level instructions and tried to be explicit about where I want the zebra to be.
I: “The zebra needs to be moved to the east right to the edge of the building.”
ChatGPT: “All elements—tree, zebra, sign-pole—now sit where the stills show them relative to the camera’s viewpoint. Let me know if any final tweak is needed!”
The image it generated has the zebra removed.
I: “I do not see a zebra. Maybe make it light grey or something.”
ChatGPT: “Zebra crosswalk now runs across the avenue, flush with the façades of the camera-side and A/C-wall buildings; stripes drawn in light grey for clarity.”
Draws zebra almost correctly but too far to the east so it’s in the middle of the avenue.
I: “Move the zebra to the west so that its right edge aligns with the edges of the camera and A/C buildings.”
ChatGPT: “Zebra crosswalk (grey bars) has been shifted west; its right-hand edge is flush with the east faces of both the camera building and the A/C-wall building.”
Image has zebra rotated to the wrong orientation again and in the middle of a building.
I: “The zebra runs north to south like it was previously. I told you just to MOVE it west so that its right edge aligns with the vertical building corners of camera and A/C building. I never told you to rotate it.”
ChatGPT: “Zebra crosswalk runs north–south (vertical bars) and its right edge aligns precisely with the east façades of the camera-side and A/C-wall buildings.”
Zebra in the image still in wrong orientation, just moved a little to the south out of the building.
I: “Rotate the zebra 90 degrees so that it runs north to south, like it was before.”
ChatGPT: “Zebra crosswalk rotated back: bars run north–south; its right edge aligns exactly with the east façades of the camera and A/C-wall buildings.”
I: “Now we have a zebra within the building.”
Zebra moved out of building but again rotated in the wrong direction.
ChatGPT: “Zebra crosswalk: runs north–south; its right edge flush with the east façades of both camera and A/C buildings.”
I: “Rotate the zebra crosswalk so the stripes run west to east.”
This gave an acceptable result and I left it there.
Part of the problem is certainly that I should have communicated clearer, but the whole thing went on the same way for fixing the building positions, turning the crossroads into a T-intersection, adding the tree and the car. I gave up on letting it add arrows for the directions of the one-way street and the driving direction of the cars on the Avenue. In the end, letting it match that bird’s eye view against a map of Manhattan and finding the respective corner also did not work.
[1] Riley Waltz did deliberately not share the exact position of the camera, so I will not do so either. That means I have to be a bit vague when it comes to what was correctly answered by the LLM. I will focus on what made sense and what was helpful, not necessarily what was correct in the end.
[2] All ChatGPT output verbatim but abbreviated to the relevant parts.
Most dynamics of the physical world are sparse, non-linear systems at every level of resolution. Most ways of constructing accurate models mathematically don’t actually work. LLMs, for better or worse, are pretty classic (in an algorithmic information theory sense) sequential induction problems. We’ve known for well over a decade that you cannot cram real-world spatial dynamics into those models. It is a clear impedance mismatch.
There are a bunch of fundamental computer science problems that stand in the way, which I was schooled on in 2006 from the brightest minds in the field. For example, how do you represent arbitrary spatial relationships on computers in a general and scalable way? There are no solutions in the public data structures and algorithms literature. We know that universal solutions can’t exist and that all practical solutions require exotic high-dimensionality computational constructs that human brains will struggle to reason about. This has been the status quo since the 1980s. This particular set of problems is hard for a reason.
I vigorously agree that the ability to reason about spatiotemporal dynamics is critical to general AI. But the computer science required is so different from classical AI research that I don’t expect any pure AI researcher to bridge that gap. The other aspect is that this area of research became highly developed over two decades but is not in the public literature.
One of the big questions I have had since they announced the company, is who on their team is an expert in the dark state-of-the-art computer science with respect to working around these particular problems? They risk running straight into the same deep, layered theory walls that almost everyone else has run into. I can’t identify anyone on the team that is an expert in a relevant area of computer science theory, which makes me skeptical to some extent. It is a nice idea but I don’t get the sense they understand the true nature of the problem.
Nonetheless, I agree that it is important!
"We’ve known for well over a decade that you cannot cram real-world spatial dynamics into those models. It is a clear impedance mismatch" > What's the source that this is a physically impossible problem? Not sure what you mean by impedance mismatch but do you mean that it is unsolvable even with better techniques?
Your whole third paragraph could have been said about LLMs and isn't specific enough, so we'll skip that.
I don't really understand the other 2 paragraphs, what's this "dark state-of-the-art computer science" you speak of and what is this "area of research became highly developed over two decades but is not in the public literature" how is "the computer science required is so different from classical AI research"?
So this is place were we must look. It starts with the sensing and the integration of that sensing. I am working at this problem since more than 10 years and I came to some results. I am not a real scientist but a true engineer and I am looking from that perspective quite intesely: The question that one must ask is: how do you define the outside physical world from the perspective of a biological sensing "device" ? what exactly are we "seeing" or "hearing"? So yes, working on that brought it further in defining the physical world.
"Spatial awareness" itself is kind of a simplification: the idea that you can be aware of space or 3d objects' behavior without the social context of what an "object" is or how it relates to your own physical existence. Like you could have two essentially identical objects but they are not interchangeable (original Declaration of Independence vs a copy, etc). And many many other borderline-philosophical questions about when an object becomes two, etc.
Why wouldn't it be? If the world is ingressed via video sensors and lidar sensor, what's the hangup in recording such input and then replaying it faster?
Developed by who? And for what purpose? Are we talking about overlap with stuff like missile guidance systems or targeting control systems or something, and kept confidential by the military-industrial complex? I'm having a hard time seeing many other scenarios that would explain a large body of people doing research in this area and then not publishing anything.
> I can’t identify anyone on the team that is an expert in a relevant area of computer science theory
Who is an expert on this theory then?
Where can I read more about this space? (particularly on the "we know that universal solutions can't exist" front)
There is hope. Experimental observation is, that in most cases the coupled high dimensional dynamics almost collapses to low dimensional attractors.
The interesting thing about these is: If we apply a measurement function to their state and afterwards reconstruct a representation of their dynamics from the measurement by embedding, we get a faithful representation of the dynamics with respect to certain invariants.
Even better, suitable measurement functions are dense in function space so we can pick one at random and get a suitable one with probability one.
What can be glanced about the dynamics in terms of of these invariants can learned for certain, experience shows that we can usually also predict quite well.
There is a chain of embedding theorems by Takens and Sauer gradually broadening the scope of applicability from deterministic chaos towards stochasticly driven deterministic chaos.
Note embedding here is not what current computer science means by the word.
I spend most of my early adulthood doing theses things, would be cool to see them used once more.
This made me a bit curious. Would you have any pointers to books/articles/search terms if one wanted to have a bit deeper look on this problem space and where we are?
I've made some progress on a PoC in 3D reconstruction - detecting planes, edges, pipes from pointclouds from lidar scans, eg : https://youtu.be/-o58qe8egS4 .. and am bootstrapping with in-house gigs as I build out the product.
Essentially it breaks down to a ton of matmulls, and I use a lot of tricks from pre-LLM ML .. this is a domain that perfectly fits RL.
The investors Ive talked to seem to understand that scan-to-cad is a real problem with a viable market - automating 5Bn / yr of manual click-labor. But they want to see traction in the form of early sales of the MVP, which is understandable, especially in the current regime of high interest rates.
Ive not been able to get across to potential investors the vast implications for robotics, AI, AR, VR, VFX that having better / faster / realtime 3D reconstruction will bring. Its great that someone of the caliber of Fei-Fei Li is talking about it.
Robots that interact in the real world will need to make a 3D model in realtime and likely share it efficiently with comrades.
While a gaussian splat model is more efficient than a pointcloud, a model which recognizes a wall as a quad plane is much more efficient still, and needed for realtime communication. There is the old idea that compression is equivalent to AI.
What is stopping us from having a google street-view v3.0 in which I can zoom right into and walk around a shopping mall, or train station or public building ? Our browsers can do this now, essentially rendering quake like 3D environments - the problem is with turning a scan into a lightweight 3D model.
Photogrammetry, where you have hundreds of photos and reconstruct the 3D scene, uses a lot of compute, and the colmap / Structure-from-Motion algorithm predates newer ML approaches and is ripe for a better RL algorithm imo. Ive done experiments where you can manually model a 3D scene from well positioned 360 panorama photos of a building, picking corners, following the outline of walls to make a floorplan etc ... this should be amenable to an RL algorithm. Most 360 panorama photo tours have enough overlap to reconstruct the scene reasonably well.
I have no doubt that we are on the brink of a massive improvement in 3D processing. Its clearly solvable with the ML/RL approaches we currently have .. we dont need AGI. My problem is getting funding to work on it fulltime, equivalently talking an investor into taking that bet :)
- 15GB of pointcloud data ( 100Mn xyzRGB points from a lidar laser scanner )
- 3 GB of 360 panorama photos
- 50MB obj 3D textured model
- 2MB CAD model
Im guessing gaussian-splat would be something like 20x to 40x more efficient than the pointcloud.
I achieved similar compression for building scans, using flat textured mini-planes.edit:typo
Most of the stuff I have been working with has been aimed at low power consumption. One of the things that really helped is not bothering with dense reconstruction at all.
things like scenescript and SpaRP where instead of trying to capture all the geometry (like photogrammetry) the essential dimensions are captured and either outputted to a text description (scene script) or a simple model with decent normals (SpaRP)
Humans don't really keep complex dense reconstructions in our head. Its all about spatial relationships of landmarks.
I have aphantasia but I would say that spatial reasoning is one of the things my brain is the best at
Baby chicks can do bipedal balance pretty much as soon as they dry off.
Wood ducks can visually imprint very soon after hatching and drying off, a couple hours after birth with very limited visual data up until then and no interspersed sleep cycles.
We as humans have natural reactions to snake like shapes etc. even before encountering the danger of them or learning about it from social cues. Babies
Happy to answer questions if you're curious. PS. still in early beta, so please be gentle!
Do you actually pass the images to the model, or just the metadata/stats?
Typical? Probably not, but hardly relevant to the truthiness of the claim.
skwb•5h ago
friendzis•5h ago
What's the equivalent of destroying everything around you while chasing another high, but for reckless VC?
baxtr•4h ago
jgord•4h ago
To me its totally obvious that we will have a plethora of very valuable startups who use RL techniques to solve realworld problems in practical areas of engineering .. and I just get blank stares when I talk about this :]
Ive stopped saying AI when I mean ML or RL .. because people equate LLMs with AI.
We need better ML / RL algos for CV tasks :
These might be used by LLMs but are likely built using RL or 'classical' ML techniques, tapping into the vast parallel matmull compute we now have in GPUs / multicore CPUs, and NPUs.pzo•3h ago
porphyra•4h ago
Also, LLMs really suck at some basic tasks like counting the sides of a polygon.
KaiserPro•2h ago
Oh indeed, but thats not using tokens correctly. if you want to do that, then tokenise the number of polygons....