in_channels=3,
channels=(320, 640, 1280, 1280),
num_res_blocks=2,
downscale_factor=16,
adapter_type="full_adapter_xl",
)
```  
The [optimizer](https://github.com/huggingface/diffusers/blob/aab6de22c33cc01fb7bc81c0807d6109e2c998c9/examples/t2i_adapter/train_t2i_adapter_sdxl.py#L952) is initialized for the T2I-Adapter parameters:  
```py
params_to_optimize = t2iadapter.parameters()
optimizer = optimizer_class(
params_to_optimize,
lr=args.learning_rate,
betas=(args.adam_beta1, args.adam_beta2),