Spaces:
Sleeping
Sleeping
""" OpenAI pretrained model functions | |
Adapted from https://github.com/openai/CLIP. Originally MIT License, Copyright (c) 2021 OpenAI. | |
""" | |
import os | |
import warnings | |
from typing import Union, List | |
import torch | |
from .model import build_model_from_openai_state_dict | |
from .pretrained import get_pretrained_url, list_pretrained_tag_models, download_pretrained_from_url | |
__all__ = ["list_openai_models", "load_openai_model"] | |
def list_openai_models() -> List[str]: | |
"""Returns the names of available CLIP models""" | |
return list_pretrained_tag_models('openai') | |
def load_openai_model( | |
name: str, | |
device: Union[str, torch.device] = "cuda" if torch.cuda.is_available() else "cpu", | |
jit=True, | |
cache_dir=None, | |
): | |
"""Load a CLIP model | |
Parameters | |
---------- | |
name : str | |
A model name listed by `clip.available_models()`, or the path to a model checkpoint containing the state_dict | |
device : Union[str, torch.device] | |
The device to put the loaded model | |
jit : bool | |
Whether to load the optimized JIT model (default) or more hackable non-JIT model. | |
cache_dir : Optional[str] | |
The directory to cache the downloaded model weights | |
Returns | |
------- | |
model : torch.nn.Module | |
The CLIP model | |
preprocess : Callable[[PIL.Image], torch.Tensor] | |
A torchvision transform that converts a PIL image into a tensor that the returned model can take as its input | |
""" | |
if get_pretrained_url(name, 'openai'): | |
model_path = download_pretrained_from_url(get_pretrained_url(name, 'openai'), cache_dir=cache_dir) | |
elif os.path.isfile(name): | |
model_path = name | |
else: | |
raise RuntimeError(f"Model {name} not found; available models = {list_openai_models()}") | |
try: | |
# loading JIT archive | |
model = torch.jit.load(model_path, map_location=device if jit else "cpu").eval() | |
state_dict = None | |
except RuntimeError: | |
# loading saved state dict | |
if jit: | |
warnings.warn(f"File {model_path} is not a JIT archive. Loading as a state dict instead") | |
jit = False | |
state_dict = torch.load(model_path, map_location="cpu") | |
if not jit: | |
try: | |
model = build_model_from_openai_state_dict(state_dict or model.state_dict()).to(device) | |
except KeyError: | |
sd = {k[7:]: v for k, v in state_dict["state_dict"].items()} | |
model = build_model_from_openai_state_dict(sd).to(device) | |
if str(device) == "cpu": | |
model.float() | |
return model | |
# patch the device names | |
device_holder = torch.jit.trace(lambda: torch.ones([]).to(torch.device(device)), example_inputs=[]) | |
device_node = [n for n in device_holder.graph.findAllNodes("prim::Constant") if "Device" in repr(n)][-1] | |
def patch_device(module): | |
try: | |
graphs = [module.graph] if hasattr(module, "graph") else [] | |
except RuntimeError: | |
graphs = [] | |
if hasattr(module, "forward1"): | |
graphs.append(module.forward1.graph) | |
for graph in graphs: | |
for node in graph.findAllNodes("prim::Constant"): | |
if "value" in node.attributeNames() and str(node["value"]).startswith("cuda"): | |
node.copyAttributes(device_node) | |
model.apply(patch_device) | |
patch_device(model.encode_image) | |
patch_device(model.encode_text) | |
# patch dtype to float32 on CPU | |
if str(device) == "cpu": | |
float_holder = torch.jit.trace(lambda: torch.ones([]).float(), example_inputs=[]) | |
float_input = list(float_holder.graph.findNode("aten::to").inputs())[1] | |
float_node = float_input.node() | |
def patch_float(module): | |
try: | |
graphs = [module.graph] if hasattr(module, "graph") else [] | |
except RuntimeError: | |
graphs = [] | |
if hasattr(module, "forward1"): | |
graphs.append(module.forward1.graph) | |
for graph in graphs: | |
for node in graph.findAllNodes("aten::to"): | |
inputs = list(node.inputs()) | |
for i in [1, 2]: # dtype can be the second or third argument to aten::to() | |
if inputs[i].node()["value"] == 5: | |
inputs[i].node().copyAttributes(float_node) | |
model.apply(patch_float) | |
patch_float(model.encode_image) | |
patch_float(model.encode_text) | |
model.float() | |
# ensure image_size attr available at consistent location for both jit and non-jit | |
model.visual.image_size = model.input_resolution.item() | |
return model | |