Files
sglang/python/sglang/srt/models/yivl.py
2024-05-21 09:13:37 -07:00

104 lines
4.0 KiB
Python

"""Inference-only Yi-VL model."""
from typing import Tuple, Iterable
import torch
import torch.nn as nn
from transformers import CLIPVisionModel, LlavaConfig
from vllm.model_executor.model_loader.weight_utils import default_weight_loader
from sglang.srt.models.llava import (
LlavaLlamaForCausalLM,
monkey_path_clip_vision_embed_forward,
)
class YiVLForCausalLM(LlavaLlamaForCausalLM):
def __init__(
self, config, quant_config = None,
) -> None:
super().__init__(config, quant_config)
self.multi_modal_projector = YiVLMultiModalProjector(self.config)
self.vision_tower_subfolder = self.config.mm_vision_tower.replace(
"./", ""
) # Everything after "./"
def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
# We have to use the subfolder of the main model directory (e.g. 01-ai/Yi-VL-6B)
self.vision_tower = CLIPVisionModel.from_pretrained(
self.config._name_or_path,
torch_dtype=torch.float16,
subfolder=self.vision_tower_subfolder,
).cuda()
self.vision_tower.eval()
self.vision_feature_layer = self.config.mm_vision_select_layer
self.vision_feature_select_strategy = self.config.mm_vision_select_feature
self.image_size = self.vision_tower.config.image_size
self.patch_size = self.vision_tower.config.patch_size
self.mm_patch_merge_type = getattr(self.config, "mm_patch_merge_type", "flat")
self.image_aspect_ratio = getattr(self.config, "image_aspect_ratio", "square")
self.image_grid_pinpoints = getattr(self.config, "image_grid_pinpoints", None)
self.image_feature_len = int((self.image_size / self.patch_size) ** 2)
if self.vision_feature_select_strategy == "patch":
pass
elif self.vision_feature_select_strategy == "cls_patch":
self.image_feature_len += 1
else:
raise ValueError(f"Unexpected select feature: {self.select_feature}")
# load mm_projector
# TODO: support TP?
projector_weights = {
"model.mm_projector.0": "multi_modal_projector.linear_1",
"model.mm_projector.1": "multi_modal_projector.ln_1",
"model.mm_projector.3": "multi_modal_projector.linear_2",
"model.mm_projector.4": "multi_modal_projector.ln_2",
"model.vision_tower.vision_tower": "vision_tower", # Update the vision tower weights if we find them in the checkpoint (it may be finetuned).
}
params_dict = dict(self.named_parameters())
weights = list(weights)
for name, loaded_weight in weights:
if "projector" in name or "vision_tower" in name:
for weight_name, param_name in projector_weights.items():
if weight_name in name:
name = name.replace(weight_name, param_name)
param = params_dict[name]
weight_loader = getattr(param, "weight_loader", default_weight_loader)
weight_loader(param, loaded_weight)
# load language model
self.language_model.load_weights(weights)
monkey_path_clip_vision_embed_forward()
class YiVLMultiModalProjector(nn.Module):
def __init__(self, config: LlavaConfig):
super().__init__()
self.linear_1 = nn.Linear(
config.vision_config.hidden_size, config.text_config.hidden_size
)
self.ln_1 = nn.LayerNorm(config.text_config.hidden_size)
self.act = nn.GELU()
self.linear_2 = nn.Linear(
config.text_config.hidden_size, config.text_config.hidden_size
)
self.ln_2 = nn.LayerNorm(config.text_config.hidden_size)
def forward(self, image_features):
hidden_states = self.linear_1(image_features)
hidden_states = self.ln_1(hidden_states)
hidden_states = self.act(hidden_states)
hidden_states = self.linear_2(hidden_states)
hidden_states = self.ln_2(hidden_states)
return hidden_states
EntryClass = YiVLForCausalLM