Stefan Baumann

@stefanabaumann.bsky.social

PhD Student at @compvis.bsky.social & @ellis.eu working on generative computer vision. Interested in extracting world understanding from models and more controlled generation. 🌐 https://stefan-baumann.eu/

Diffusion models treat every part of an image equally. → Same number of steps. Same compute. But images aren’t uniform. 🤔 Some regions are easy, others are hard. So why force the model to treat them the same? 🧵

Video diffusion models learn motion indirectly through pixels. But motion itself is much lower-dimensional. We introduce 64× temporally compressed motion embeddings that directly capture scene dynamics. This enables efficient planning -> 10,000× faster than video models. 🧵👇

Last year Molmo set SOTA on image benchmarks + pioneered image pointing. Millions of downloads later, Molmo 2 brings Molmo’s grounded multimodal capabilities to video 🎥—and leads many open models on challenging industry video benchmarks. 🧵

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🤔 What if you could generate an entire image using just one continuous token? 💡 It works if we leverage a self-supervised representation! Meet RepTok🦎: A generative model that encodes an image into a single continuous latent while keeping realism and semantics. 🧵 👇

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🤔 What happens when you poke a scene — and your model has to predict how the world moves in response? We built the Flow Poke Transformer (FPT) to model multi-modal scene dynamics from sparse interactions. It learns to predict the 𝘥𝘪𝘴𝘵𝘳𝘪𝘣𝘶𝘵𝘪𝘰𝘯 of motion itself 🧵👇

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“Everyone knows” what an autoencoder is… but there's an important complementary picture missing from most introductory material. In short: we emphasize how autoencoders are implemented—but not always what they represent (and some of the implications of that representation).🧵

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I'm calling it now, GSPO will be the next big hype in LLM RL algos after GRPO. It makes so much more sense intuitively to work on a sequence rather than on a token level when our rewards are on a sequence level.

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What I like to do when considering a new dataset is to train a simple classifier and look at 'the most confident errors'. Recently with NICO: Apart from a class, the images have a context, one of them is 'autumn'. There is also a pumpkin class. Surprise surprise, many autumn images contain pumpkins.

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How to schedule a meeting? When you ask for a meeting with others, you are asking for their time. You are asking for their most valuable, finite resource to benefit yourself (e.g., for advice, networking, questions, and opportunities). Here are some tips that I found useful.

Do you like the power of diffusion features for semantic correspondence but dread running an expensive ~1B model to get them? What if you could have even better features at a fraction of the cost? If this sounds enticing, take a look at this paper! ⬇️

Frank Fundel@frankfundel.bsky.social · 2y ago

Did you know you can distill the capabilities of a large diffusion model into a small ViT? ⚗️ We showed exactly that for a fundamental task: semantic correspondence📍 A thread 🧵👇

Ever wondered if diffusion features could do better without all the noise? 🤔 Turns out they can! We show how adapting the backbone unlocks clean, powerful features for better results across the board. 🚀🧹 Check it out! ⬇️

Nick Stracke@rmsnorm.bsky.social · 2y ago

🤔 Why do we extract diffusion features from noisy images? Isn’t that destroying information? Yes, it is - but we found a way to do better. 🚀 Here’s how we unlock better features, no noise, no hassle. 📝 Project Page: compvis.github.io/cleandift 💻 Code: github.com/CompVis/clea... 🧵👇

Blog post link: diffusionflow.github.io/ Despite seeming similar, there is some confusion in the community about the exact connection between the two frameworks. We aim to clear up the confusion by showing how to convert one framework to another, for both training and sampling.

Diffusion Meets Flow Matching

Flow matching and diffusion models are two popular frameworks in generative modeling. Despite seeming similar, there is some confusion in the community about their exact connection. In this post, we a...

diffusionflow.github.io