  Current large vision-language models (VLMs) often encounter challenges such
as insufficient capabilities of a single visual component and excessively long
visual tokens. These issues can limit the model's effectiveness in accurately
interpreting complex visual information and over-lengthy contextual
information. Addressing these challenges is crucial for enhancing the
performance and applicability of VLMs. This paper proposes the use of ensemble
experts technique to synergizes the capabilities of individual visual encoders,
including those skilled in image-text matching, OCR, image segmentation, etc.
This technique introduces a fusion network to unify the processing of outputs
from different visual experts, while bridging the gap between image encoders
and pre-trained LLMs. In addition, we explore different positional encoding
schemes to alleviate the waste of positional encoding caused by lengthy image
feature sequences, effectively addressing the issue of position overflow and
length limitations. For instance, in our implementation, this technique
significantly reduces the positional occupancy in models like SAM, from a
substantial 4096 to a more efficient and manageable 64 or even down to 1.
Experimental results demonstrate that VLMs with multiple experts exhibit
consistently superior performance over isolated visual encoders and mark a
significant performance boost as more experts are integrated. We have
open-sourced the training code used in this report. All of these resources can
be found on our project website.
