
Multimodal @Apple, previously at @EPFL_en, @RIKEN_AIP
Joined October 2018
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Have you ever been bothered by the constraints of fixed-sized 2D-grid tokenizers? We present FlexTok, a flexible-length 1D tokenizer that enables autoregressive models to describe images in a coarse-to-fine manner.
flextok.epfl.ch
arxiv.org/abs/2502.13967
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Great opportunity to work on exciting topics like encoder-free multimodal pre-training, accurate scaling laws, and building better data mixtures. Join us here in Zurich!
🇨🇭 We're hiring a research intern at Apple Zurich! Come work on multimodal pretraining and scaling laws with us (9+ months, could start asap).
📩 Send your CV and representative work to [email protected]
Roman Bachmann retweeted
A major question in multimodal modeling is how to leverage strong pre-trained models, such as industry-scale LLMs and VLMs, during training to avoid starting from scratch. This is important as the demand for rich and domain-specific multimodal models continues to increase, while training them from scratch is obviously impractical due to limited data and compute.
The so-called “any-to-any” multimodal models can model a large diverse dictionary of modalities. That’s good. Their downside is that their architectures are often not decoder-only, which has limited their performance in practice and prevents them from leveraging strong pre-trained decoder-only models as priors.
We are releasing MODUS (@icmlconf '26) a decoder-only any-to-any multimodal model to address some of these questions. A single transformer decoder predicts any modality from any others with no modality-specific heads, losses, or task pipelines. We show efficient adaptation of established models, e.g., BAGEL, to rich any-to-any multimodal modeling.
We are releasing 14B to 77B parameter models. All materials are open-source. The download links and demos here modus-multimodal.epfl.ch/
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Roman Bachmann retweeted
Flying to Seoul to present our #ICML2026 Spotlight VideoFlexTok! Poster Session 4 (14:30-16:15) on Wednesday, poster 3001. Come say hi!
Also don’t miss the expo talk by @oguzhanthefatih on Monday on (Video)FlexTok!
Are all videos worth the same number of tokens? Whether rich in motion or visually minimal, standard 3D-grid tokenizers treat them equally. We present VideoFlexTok, which represents videos using a flexible-length, coarse-to-fine sequence of tokens.
Page: videoflextok.epfl.ch
Demo: huggingface.co/spaces/EPFL-V…
Paper: arxiv.org/abs/2604.12887
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Roman Bachmann retweeted
Heading to ICML 2026 in Seoul! 🇰🇷
🎙️I’ll be giving an Expo Talk on Monday on VideoFlexTok (Spotlight), our work on flexible-length, coarse-to-fine video tokenization: videoflextok.epfl.ch
We’ll also present the following papers:
• (1D) Ordered Tokens Enable Efficient Test-Time Search soto.epfl.ch
• MODUS: Decoder-only Any-to-Any Modeling of Diverse Modalities modus-multimodal.epfl.ch
Come say hi! We’re hiring interns and full-time researchers at Apple in Zürich. If you’re interested, let’s chat at ICML or send your CV and relevant work to [email protected].
Happening tomorrow morning! Join us at the Any-to-Any Multimodal Learning workshop with a fantastic lineup of speakers!
We're hiring for MINT-Zürich 🇨🇭 @Apple , interns + full-time to build multimodal foundation models, with research across pre-training, post-training, agents, and world models!
Email us at [email protected] with CV + relevant work, and apply to jobs.apple.com/en-us/details…
At #CVPR2026 in Denver this week btw, feel free to say hi 👋
Roman Bachmann retweeted
Test-time scaling, reasoning, and generally search-like processes clearly drive significant gains in LLMs. Largely owed to the structure of language. One would think the same could apply to non-linguistic domains, like image generation, but that obviously depends on whether the structure of the domain's representation lends itself to search.
1D ordered tokens (e.g., image FlexTok, video FlexTok) seem like a natural fit since they enable a step-by-step coarse-to-fine generation. We investigated that and found they indeed enable search and scale far better with test-time compute than 2D grids. See the visuals on the webpage. Appearing in @icmlconf 2026.
🔗 soto.epfl.ch
📄 arxiv.org/abs/2604.15453,
Excited to release Weblica! Two recipes for scaling visual web-agent training, bypassing live-web slowness and irreproducibility: deterministic HTTP cache replay, and generating thousands of diverse synthetic envs automatically using Claude Code.
Excited to share Weblica, a framework for scalable and reproducible training environments for visual web agents!
📄 arxiv.org/abs/2605.06761
What I find especially exciting: producing this many diverse, interactive environments would have been prohibitively expensive not long ago. Strong coding agents have made this tractable; Weblica spans thousands of sites across varied domains, capabilities, and visual styles.
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Roman Bachmann retweeted
This study will be presented at @iclr_conf on Thursday at 15:15. Much has progressed since we did the study a few months ago, but many of the observations are still relevant. fm-vision-evals.epfl.ch/
We benchmarked leading multimodal foundation models (GPT-4o, Claude 3.5 Sonnet, Gemini, Llama, etc.) on standard computer vision tasks—from segmentation to surface normal estimation—using standard datasets like COCO and ImageNet.
These models have made remarkable progress; however, it is unclear exactly where they stand in terms of understanding vision in detail. Especially when it comes to tasks beyond question-answering. How well do they understand an object's segments or geometry?
Our analyses yield an assessment that is quantitatively and qualitatively detailed and is compatible with evaluations developed in the field of computer vision over the past decades.
Observed trends:
🔹 The foundation models consistently underperform task-specific SOTA models across all tasks. However, they are respectable generalists, which is remarkable as they are presumably trained primarily on image-text-based tasks.
🔹 They perform semantic tasks notably better than geometric ones.
🔹 GPT-4o performs the best among non-reasoning models, getting the top position in 4 out of 6 tasks.
🔹 Reasoning models, e.g., o3, show improvements in geometric tasks.
🔹 The 'image generation' models, e.g., GPT-40 Image Generation, which have been natively trained multimodally, exhibit quirks. E.g., hallucinated objects, misalignment between the input and output, etc.
🔹 While the prompting techniques affect performance, better models exhibit less sensitivity to variations in prompts. We control for the variance introduced by the prompting methods in our experiments.
🌐 Detailed analyses, visualizations: fm-vision-evals.epfl.ch
⌨️ code: github.com/EPFL-VILAB/fm-vis…
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Roman Bachmann retweeted
Are all videos worth the same number of tokens? Whether rich in motion or visually minimal, standard 3D-grid tokenizers treat them equally. We present VideoFlexTok, which represents videos using a flexible-length, coarse-to-fine sequence of tokens.
Page: videoflextok.epfl.ch
Demo: huggingface.co/spaces/EPFL-V…
Paper: arxiv.org/abs/2604.12887
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Roman Bachmann retweeted
🚀 Any-to-Any Multimodal Learning Workshop @ CVPR 2026
Exploring unified learning across vision, language, audio, 3D, video, and beyond.
📷 a2a-mml-2026.vercel.app
📷 Submission deadline: March 01, 2026
#Multimodal #AnyToAny #CVPR2026
🚨 Join us at #CVPR2026 in Denver! If you're working on any-to-any multimodal learning, we'd love to see your submissions.
🔗 a2a-mml-2026.vercel.app/
📅 Deadline: March 1st AOE
🚀 Any-to-Any Multimodal Learning Workshop @ CVPR 2026
Exploring unified learning across vision, language, audio, 3D, video, and beyond.
🔗 a2a-mml-2026.vercel.app
📢 Call for papers!
📆 Submission deadline: March 01, 2026
#CVPR2026 #Multimodal #AnyToAny
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Roman Bachmann retweeted
📢 Phillip Isola @phillip_isola, Saining Xie @sainingxie, and I @zamir_ar are hiring joint postdocs in machine learning with a focus on multimodal learning. What brings us together is our shared interest in multimodality and our intention to move the boundaries of current approaches in this area. Our team has access to substantial compute resources through the Swiss National Supercomputing Centre Swiss AI initiative and our industry partners. The postdocs will work at the intersection of our groups. For now the positions will be based at EPFL with visiting stays at MIT and NYU, and will be co-advised by two or all three of us.
🔗 Apply here if interested: forms.gle/BXvNpqCtgk7Z1ncs5
Roman Bachmann retweeted
I'll give a workshop talk on multimodel modeling at #NeurIPS2025 covering: Any-to-Any modeling (4M image version, 3D version, and video version), FlexTok (image version, video version, and generation by search on tokens), and Specialization of multimodal models.
flextok.epfl.ch/
4m.epfl.ch/
tst-vision.epfl.ch/
Multimodal Superintelligence Workshop.
Roman Bachmann retweeted
We will continue to hire international interns through the Summer@EPFL program. Many of our great past projects had an intern contributing to them:
viper.epfl.ch/
visual-morphology.epfl.ch/
4m.epfl.ch/
clipasso.github.io/clipasso/
omnidata.vision/
Deadline the end of this week.
summer.epfl.ch/
Roman Bachmann retweeted
Two talks today (Monday) at @ICCVConference:
1. How many pixels do we need to see?
3:10 PM-3:50 PM at 305 A.
responsible-imaging.github.i…
2. Multimodal Scene Understanding.
4:40 PM-5:10 PM at 325 B.
s3dsgr.github.io/





















