InvokeAI/invokeai/backend/spandrel_image_to_image_model.py

64 lines
2.4 KiB
Python

from pathlib import Path
from typing import Any, Optional
import torch
from spandrel import ImageModelDescriptor, ModelLoader
from invokeai.backend.raw_model import RawModel
class SpandrelImageToImageModel(RawModel):
"""A wrapper for a Spandrel Image-to-Image model.
The main reason for having a wrapper class is to integrate with the type handling of RawModel.
"""
def __init__(self, spandrel_model: ImageModelDescriptor[Any]):
self._spandrel_model = spandrel_model
@classmethod
def load_from_file(cls, file_path: str | Path):
model = ModelLoader().load_from_file(file_path)
if not isinstance(model, ImageModelDescriptor):
raise ValueError(
f"Loaded a spandrel model of type '{type(model)}'. Only image-to-image models are supported "
"('ImageModelDescriptor')."
)
return cls(spandrel_model=model)
@classmethod
def load_from_state_dict(cls, state_dict: dict[str, torch.Tensor]):
model = ModelLoader().load_from_state_dict(state_dict)
if not isinstance(model, ImageModelDescriptor):
raise ValueError(
f"Loaded a spandrel model of type '{type(model)}'. Only image-to-image models are supported "
"('ImageModelDescriptor')."
)
return cls(spandrel_model=model)
def supports_dtype(self, dtype: torch.dtype) -> bool:
"""Check if the model supports the given dtype."""
if dtype == torch.float16:
return self._spandrel_model.supports_half
elif dtype == torch.bfloat16:
return self._spandrel_model.supports_bfloat16
elif dtype == torch.float32:
# All models support float32.
return True
else:
raise ValueError(f"Unexpected dtype '{dtype}'.")
def to(
self,
device: Optional[torch.device] = None,
dtype: Optional[torch.dtype] = None,
non_blocking: bool = False,
) -> None:
"""Note: Some models have limited dtype support. Call supports_dtype(...) to check if the dtype is supported.
Note: The non_blocking parameter is currently ignored."""
# TODO(ryand): spandrel.ImageModelDescriptor.to(...) does not support non_blocking. We will access the model
# directly if we want to apply this optimization.
self._spandrel_model.to(device=device, dtype=dtype)