imaginAIry/imaginairy/vendored/blip/blip_nlvr.py
Bryce 316114e660 docs: add docstrings
Wrote an openai script and custom prompt to generate them.
2023-12-15 14:32:01 -08:00

119 lines
4.0 KiB
Python

"""Classes for visual-language reasoning"""
import torch
import torch.nn.functional as F
from models.blip import create_vit, init_tokenizer, is_url
from models.med import BertConfig
from models.nlvr_encoder import BertModel
from models.vit import interpolate_pos_embed
from timm.models.hub import download_cached_file
from torch import nn
class BLIP_NLVR(nn.Module):
def __init__(
self,
med_config="configs/med_config.json",
image_size=480,
vit="base",
vit_grad_ckpt=False,
vit_ckpt_layer=0,
):
"""
Args:
med_config (str): path for the mixture of encoder-decoder model's configuration file
image_size (int): input image size
vit (str): model size of vision transformer.
"""
super().__init__()
self.visual_encoder, vision_width = create_vit(
vit, image_size, vit_grad_ckpt, vit_ckpt_layer, drop_path_rate=0.1
)
self.tokenizer = init_tokenizer()
med_config = BertConfig.from_json_file(med_config)
med_config.encoder_width = vision_width
self.text_encoder = BertModel(config=med_config, add_pooling_layer=False)
self.cls_head = nn.Sequential(
nn.Linear(
self.text_encoder.config.hidden_size,
self.text_encoder.config.hidden_size,
),
nn.ReLU(),
nn.Linear(self.text_encoder.config.hidden_size, 2),
)
def forward(self, image, text, targets, train=True):
image_embeds = self.visual_encoder(image)
image_atts = torch.ones(image_embeds.size()[:-1], dtype=torch.long).to(
image.device
)
image0_embeds, image1_embeds = torch.split(image_embeds, targets.size(0))
text = self.tokenizer(text, padding="longest", return_tensors="pt").to(
image.device
)
text.input_ids[:, 0] = self.tokenizer.enc_token_id
output = self.text_encoder(
text.input_ids,
attention_mask=text.attention_mask,
encoder_hidden_states=[image0_embeds, image1_embeds],
encoder_attention_mask=[
image_atts[: image0_embeds.size(0)],
image_atts[image0_embeds.size(0) :],
],
return_dict=True,
)
hidden_state = output.last_hidden_state[:, 0, :]
prediction = self.cls_head(hidden_state)
if train:
loss = F.cross_entropy(prediction, targets)
return loss
else:
return prediction
def blip_nlvr(pretrained="", **kwargs):
model = BLIP_NLVR(**kwargs)
if pretrained:
model, msg = load_checkpoint(model, pretrained)
print("missing keys:")
print(msg.missing_keys)
return model
def load_checkpoint(model, url_or_filename):
if is_url(url_or_filename):
cached_file = download_cached_file(
url_or_filename, check_hash=False, progress=True
)
checkpoint = torch.load(cached_file, map_location="cpu")
elif os.path.isfile(url_or_filename):
checkpoint = torch.load(url_or_filename, map_location="cpu")
else:
raise RuntimeError("checkpoint url or path is invalid")
state_dict = checkpoint["model"]
state_dict["visual_encoder.pos_embed"] = interpolate_pos_embed(
state_dict["visual_encoder.pos_embed"], model.visual_encoder
)
for key in list(state_dict.keys()):
if "crossattention.self." in key:
new_key0 = key.replace("self", "self0")
new_key1 = key.replace("self", "self1")
state_dict[new_key0] = state_dict[key]
state_dict[new_key1] = state_dict[key]
elif "crossattention.output.dense." in key:
new_key0 = key.replace("dense", "dense0")
new_key1 = key.replace("dense", "dense1")
state_dict[new_key0] = state_dict[key]
state_dict[new_key1] = state_dict[key]
msg = model.load_state_dict(state_dict, strict=False)
print("load checkpoint from %s" % url_or_filename)
return model, msg