File size: 4,613 Bytes
34f251f
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
from typing import Optional

from transformers import AutoModelForCausalLM, AutoTokenizer, AutoConfig
import torch

from .phEYE import phEYE
from .wrapper_lm import phEYELMMixin
from .utils import extend_instance
from .encoder import Encoder


def create_model_and_transforms(
    clip_vision_encoder_path: str,
    lang_decoder_path: str,
    tokenizer_path: str,
    dtype,
    cross_attn_every_n_layers: int = 1,
    use_local_files: bool = False,
    decoder_layers_attr_name: str = None,
    freeze_lm_embeddings: bool = True,
    cache_dir: Optional[str] = None,
    level: int = 2,
    encoder_dtype : torch.dtype = None,
    decoder_dtype : torch.dtype = None,
    use_dropout : bool = False,
    **pheye_kwargs,
):
    """
    Initialize a phEYE model from a pretrained vision encoder and language encoder.
    Appends special tokens to the tokenizer and freezes backbones.

    Args:
        clip_vision_encoder_path (str): path to pretrained clip model (e.g. "ViT-B-32")
        clip_vision_encoder_pretrained (str): name of pretraining dataset for clip model (e.g. "laion2b_s32b_b79k")
        lang_encoder_path (str): path to pretrained language encoder
        tokenizer_path (str): path to pretrained tokenizer
        cross_attn_every_n_layers (int, optional): determines how often to add a cross-attention layer. Defaults to 1.
        use_local_files (bool, optional): whether to use local files. Defaults to False.
        decoder_layers_attr_name (str, optional): name of the decoder layers attribute. Defaults to None.
        freeze_lm_embeddings (bool, optional): whether to freeze LM input embeddings when configuring Perceiver.
        cache_dir (str, optional): path to cache directory for downloading OpenClip/HF weights.
    Returns:
        phEYE: phEYE model from pretrained vision and language encoders
        Image processor: Pipeline to preprocess input images
        Tokenizer: A tokenizer for the language model
    """

    vision_encoder = Encoder(clip_vision_encoder_path, level=level, dtype=encoder_dtype, use_dropout=use_dropout)


    text_tokenizer = AutoTokenizer.from_pretrained(
        tokenizer_path,
        local_files_only=use_local_files,
        trust_remote_code=True,
        cache_dir=cache_dir,
    )

    if text_tokenizer.pad_token is None:
        text_tokenizer.pad_token = text_tokenizer.eos_token
    
    #print(lang_decoder_path)
    lang_config = AutoConfig.from_pretrained(lang_decoder_path)
    #print(lang_config)
    lang_encoder = AutoModelForCausalLM.from_config(
        lang_config,
        #local_files_only=use_local_files,
        #trust_remote_code=True,
        torch_dtype=decoder_dtype
)

    lang_encoder.config.decoder_start_token_id = None
    lang_encoder.config.pad_token_id = text_tokenizer.pad_token_id

    # convert LM to phEYELM
    extend_instance(lang_encoder, phEYELMMixin)

    if decoder_layers_attr_name is None:
        decoder_layers_attr_name = _infer_decoder_layers_attr_name(lang_encoder)
    lang_encoder.set_decoder_layers_attr_name(decoder_layers_attr_name)

    model = phEYE(
        vision_encoder,
        lang_encoder,
        vis_dim=vision_encoder.vision_model.config.hidden_size,
        cross_attn_every_n_layers=cross_attn_every_n_layers,
        dtype=dtype,
        **pheye_kwargs,
    )

    # Freeze all parameters
    model.lang_encoder.requires_grad_(False)
    assert sum(p.numel() for p in model.lang_encoder.parameters() if p.requires_grad) == 0

    # Unfreeze perceiver, cross_attn_layers, and LM input embeddings
    model.lang_encoder.cross_attn_layers.requires_grad_(True)
    if not freeze_lm_embeddings:
        model.lang_encoder.get_input_embeddings().requires_grad_(True)

    print(
        f"phEYE model initialized with {sum(p.numel() for p in model.parameters() if p.requires_grad)} trainable parameters"
    )

    return model, text_tokenizer


def _infer_decoder_layers_attr_name(model):
    for k in __KNOWN_DECODER_LAYERS_ATTR_NAMES:
        if k.lower() in model.__class__.__name__.lower():
            return __KNOWN_DECODER_LAYERS_ATTR_NAMES[k]

    raise ValueError(
        f"We require the attribute name for the nn.ModuleList in the decoder storing the transformer block layers. Please supply this string manually."
    )


__KNOWN_DECODER_LAYERS_ATTR_NAMES = {
    "opt": "model.decoder.layers",
    "gpt": "transformer.h",
    "gpt-j": "transformer.h",
    "pythia": "gpt_neox.layers",
    "llama": "model.layers",
    "gptneoxforcausallm": "gpt_neox.layers",
    "mpt": "transformer.blocks",
    "mosaicgpt": "transformer.blocks",
    "phi" : "model.layers"
}