Meta-Transformer: A Unified Framework for Multimodal Learning
Authors: name: Yiyuan Zhang, name: Kaixiong Gong, name: Kaipeng Zhang, name: Hongsheng Li, name: Yu Qiao, name: Wanli Ouyang, name: Xiangyu Yue

Multimodal learning aims to build models that can process and relate
information from multiple modalities. Despite years of development in this
field, it still remains challenging to design a unified network for processing
various modalities (e.g. natural language, 2D images, 3D point
clouds, audio, video, time series, tabular data) due to the inherent gaps among
them. In this work, we propose a framework, named Meta-Transformer, that
leverages a frozen encoder to perform multimodal perception without
any paired multimodal training data. In Meta-Transformer, the raw input data
from various modalities are mapped into a shared token space, allowing a
subsequent encoder with frozen parameters to extract high-level semantic
features of the input data. Composed of three main components: a unified data
tokenizer, a modality-shared encoder, and task-specific heads for downstream
tasks, Meta-Transformer is the first framework to perform unified learning
across 12 modalities with unpaired data. Experiments on different benchmarks
reveal that Meta-Transformer can handle a wide range of tasks including
fundamental perception (text, image, point cloud, audio, video), practical
application (X-Ray, infrared, hyperspectral, and IMU), and data mining (graph,
tabular, and time-series). Meta-Transformer indicates a promising future for
developing unified multimodal intelligence with transformers. Code will be
available at https://github.com/invictus717/MetaTransformer