Goto

Collaborating Authors

 Ghosh, Soham


Pixtral 12B

arXiv.org Artificial Intelligence

We introduce Pixtral-12B, a 12--billion-parameter multimodal language model. Pixtral-12B is trained to understand both natural images and documents, achieving leading performance on various multimodal benchmarks, surpassing a number of larger models. Unlike many open-source models, Pixtral is also a cutting-edge text model for its size, and does not compromise on natural language performance to excel in multimodal tasks. Pixtral uses a new vision encoder trained from scratch, which allows it to ingest images at their natural resolution and aspect ratio. This gives users flexibility on the number of tokens used to process an image. Pixtral is also able to process any number of images in its long context window of 128K tokens. Pixtral 12B substanially outperforms other open models of similar sizes (Llama-3.2 11B \& Qwen-2-VL 7B). It also outperforms much larger open models like Llama-3.2 90B while being 7x smaller. We further contribute an open-source benchmark, MM-MT-Bench, for evaluating vision-language models in practical scenarios, and provide detailed analysis and code for standardized evaluation protocols for multimodal LLMs. Pixtral-12B is released under Apache 2.0 license.


VideoCoCa: Video-Text Modeling with Zero-Shot Transfer from Contrastive Captioners

arXiv.org Artificial Intelligence

Given a well-pretrained imagetext reuses a pretrained image-text contrastive captioner foundation model, it is natural to question whether any (CoCa) model and adapt it to video-text tasks with minimal heavy video-specific adaptor or many video-specific data is extra training. While previous works adapt image-text needed when transferring to video-text modelling models with various cross-frame fusion modules, we find In this paper, we explore an efficient approach to establish that the generative attentional pooling and contrastive attentional a foundational video-text model for tasks including pooling layers in CoCa are instantly adaptable to open-vocabulary video classification, text-to-video retrieval, flattened frame embeddings, yielding state-of-the-art results video captioning and video question-answering. We on zero-shot video classification and zero-shot text-to-video present VideoCoCa, a minimalist approach that extends retrieval. Furthermore, we explore lightweight finetuning the image-text contrastive captioners (CoCa) [68] to videotext on top of VideoCoCa, and achieve strong results on video tasks. The design principle of VideoCoCa is to maximally question-answering and video captioning.


Concurrent Meta Reinforcement Learning

arXiv.org Artificial Intelligence

State-of-the-art meta reinforcement learning algorithms typically assume the setting of a single agent interacting with its environment in a sequential manner. A negative side-effect of this sequential execution paradigm is that, as the environment becomes more and more challenging, and thus requiring more interaction episodes for the meta-learner, it needs the agent to reason over longer and longer time-scales. To combat the difficulty of long time-scale credit assignment, we propose an alternative parallel framework, which we name "Concurrent Meta-Reinforcement Learning" (CMRL), that transforms the temporal credit assignment problem into a multi-agent reinforcement learning one. In this multi-agent setting, a set of parallel agents are executed in the same environment and each of these "rollout" agents are given the means to communicate with each other. The goal of the communication is to coordinate, in a collaborative manner, the most efficient exploration of the shared task the agents are currently assigned. This coordination therefore represents the meta-learning aspect of the framework, as each agent can be assigned or assign itself a particular section of the current task's state space. This framework is in contrast to standard RL methods that assume that each parallel rollout occurs independently, which can potentially waste computation if many of the rollouts end up sampling the same part of the state space. Furthermore, the parallel setting enables us to define several reward sharing functions and auxiliary losses that are non-trivial to apply in the sequential setting. We demonstrate the effectiveness of our proposed CMRL at improving over sequential methods in a variety of challenging tasks.