minimind-v/model/model_vlm.py

307 lines
12 KiB
Python

import os
import torch
import warnings
from transformers.generation.utils import GenerateOutput
from .model_minimind import *
from typing import Optional, Tuple, List, Callable
from torch import nn
from transformers import CLIPProcessor, CLIPModel, GenerationConfig, LogitsProcessorList, StoppingCriteriaList
from typing import List
warnings.filterwarnings('ignore')
class VLMConfig(MiniMindConfig):
model_type = "minimind-v"
def __init__(
self,
image_special_token: str = '@' * 196,
image_ids: List = [34] * 196,
**kwargs,
):
self.image_special_token = image_special_token
self.image_ids = image_ids
super().__init__(**kwargs)
class VisionProj(nn.Module):
def __init__(self, ve_hidden_size=768, hidden_size=512):
super().__init__()
self.ve_hidden_size = ve_hidden_size
self.hidden_size = hidden_size
self.vision_proj = nn.Sequential(
nn.Linear(self.ve_hidden_size, self.hidden_size)
)
def forward(self, image_encoders):
vision_proj = self.vision_proj(image_encoders)
return vision_proj
# 继承自语言模型
class MiniMindVLM(MiniMindForCausalLM):
config_class = VLMConfig
def __init__(self, params: VLMConfig = None, vision_model_path="./model/vision_model/clip-vit-base-patch16"):
super().__init__(params)
if not params: params = VLMConfig()
self.params = params
self.vision_encoder, self.processor = self.__class__.get_vision_model(vision_model_path)
self.vision_proj = VisionProj(hidden_size=params.hidden_size)
@staticmethod
def get_vision_model(model_path: str):
from transformers import logging as hf_logging
hf_logging.set_verbosity_error()
if not os.path.exists(model_path):
return None, None
model = CLIPModel.from_pretrained(model_path)
processor = CLIPProcessor.from_pretrained(model_path)
# 冻结 vision_encoder 的所有参数
for param in model.parameters():
param.requires_grad = False
return model.eval(), processor
@staticmethod
def image2tensor(image, processor):
if image.mode in ['RGBA', 'LA']: image = image.convert('RGB')
inputs = processor(images=image, return_tensors="pt")['pixel_values']
return inputs
@staticmethod
def get_image_embeddings(image_tensors, vision_model):
with torch.no_grad():
outputs = vision_model.vision_model(pixel_values=image_tensors)
img_embedding = outputs.last_hidden_state[:, 1:, :].squeeze()
return img_embedding
def count_vision_proj(self, tokens, h, vision_tensors=None, seqlen=512):
def find_indices(tokens, image_ids):
image_ids_tensor = torch.tensor(image_ids).to(tokens.device)
len_image_ids = len(image_ids)
if len_image_ids > tokens.size(1):
return None
tokens_view = tokens.unfold(1, len_image_ids, 1)
matches = (tokens_view == image_ids_tensor).all(dim=2)
return {
batch_idx: [(idx.item(), idx.item() + len_image_ids - 1) for idx in
matches[batch_idx].nonzero(as_tuple=True)[0]]
for batch_idx in range(tokens.size(0)) if matches[batch_idx].any()
} or None
image_indices = find_indices(tokens, self.params.image_ids)
if vision_tensors is not None and image_indices:
vision_proj = self.vision_proj(vision_tensors)
if len(vision_proj.shape) == 3:
vision_proj = vision_proj.unsqueeze(0)
new_h = []
for i in range(h.size(0)):
if i in image_indices:
h_i = h[i]
img_idx = 0
for start_idx, end_idx in image_indices[i]:
if img_idx < vision_proj.size(1):
h_i = torch.cat((h_i[:start_idx], vision_proj[i][img_idx], h_i[end_idx + 1:]), dim=0)[
:seqlen]
img_idx += 1
new_h.append(h_i)
else:
new_h.append(h[i])
return torch.stack(new_h, dim=0)
return h
def forward(self,
input_ids: Optional[torch.Tensor] = None,
attention_mask: Optional[torch.Tensor] = None,
past_key_values: Optional[List[Tuple[torch.Tensor, torch.Tensor]]] = None,
use_cache: bool = False,
logits_to_keep: Union[int, torch.Tensor] = 0,
pixel_values: Optional[torch.FloatTensor] = None,
**args):
batch_size, seq_length = input_ids.shape
past_key_values = past_key_values or [None] * len(self.model.layers)
start_pos = past_key_values[0][0].shape[1] if past_key_values[0] is not None else 0
hidden_states = self.model.dropout(self.model.embed_tokens(input_ids))
if pixel_values is not None and start_pos == 0:
if len(pixel_values.shape) == 6:
pixel_values = pixel_values.squeeze(2)
bs, num, c, im_h, im_w = pixel_values.shape
stack_dim = 1 if bs > 1 else 0
vision_tensors = torch.stack([
MiniMindVLM.get_image_embeddings(pixel_values[:, i, :, :, :], self.vision_encoder)
for i in range(num)
], dim=stack_dim)
hidden_states = self.count_vision_proj(tokens=input_ids, h=hidden_states, vision_tensors=vision_tensors,
seqlen=input_ids.shape[1])
position_embeddings = (
self.model.freqs_cos[start_pos:start_pos + seq_length],
self.model.freqs_sin[start_pos:start_pos + seq_length]
)
presents = []
for layer_idx, (layer, past_key_value) in enumerate(zip(self.model.layers, past_key_values)):
hidden_states, present = layer(
hidden_states,
position_embeddings,
past_key_value=past_key_value,
use_cache=use_cache,
attention_mask=attention_mask
)
presents.append(present)
hidden_states = self.model.norm(hidden_states)
aux_loss = sum(
layer.mlp.aux_loss
for layer in self.model.layers
if isinstance(layer.mlp, MOEFeedForward)
)
slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
logits = self.lm_head(hidden_states[:, slice_indices, :])
self.OUT.__setitem__('last_hidden_state', hidden_states)
self.OUT.__setitem__('logits', logits)
self.OUT.__setitem__('aux_loss', aux_loss)
self.OUT.__setitem__('past_key_values', presents)
return self.OUT
## 以下函数使用gpt生成
def sample_logits(self, logits: torch.Tensor, temperature: float = 1.0, top_p: float = 1.0) -> torch.Tensor:
if temperature != 1.0:
logits = logits / (temperature + 1e-6)
probs = F.softmax(logits, dim=-1)
if top_p < 1.0:
sorted_probs, sorted_indices = torch.sort(probs, descending=True)
cumulative_probs = torch.cumsum(sorted_probs, dim=-1)
sorted_indices_to_remove = cumulative_probs > top_p
sorted_indices_to_remove[:, 1:] = sorted_indices_to_remove[:, :-1].clone()
sorted_indices_to_remove[:, 0] = False
indices_to_remove = torch.zeros_like(probs, dtype=torch.bool)
indices_to_remove.scatter_(1, sorted_indices, sorted_indices_to_remove)
probs = probs.masked_fill(indices_to_remove, 0.0)
probs = probs / probs.sum(dim=-1, keepdim=True)
return torch.multinomial(probs, num_samples=1)
@torch.inference_mode()
def generate(
self,
input_ids: torch.LongTensor,
pixel_values: Optional[torch.FloatTensor] = None,
max_new_tokens: Optional[int] = 128,
do_sample: bool = False,
temperature: float = 1.0,
top_p: float = 1.0,
num_return_sequences: int = 1,
attention_mask: Optional[torch.Tensor] = None,
pad_token_id: int = 0,
eos_token_id: int = 2,
streamer=None,
use_cache: bool = True,
**kwargs
) -> Union[GenerateOutput, torch.LongTensor]:
generated = []
for batch_idx in range(input_ids.size(0)):
input_ids_i = input_ids[batch_idx][input_ids[batch_idx] != pad_token_id].unsqueeze(0)
pixel_values_i = pixel_values[batch_idx:batch_idx + 1] if pixel_values is not None else None
for _ in range(num_return_sequences):
output = self._stream(
input_ids=input_ids_i,
pixel_values=pixel_values_i,
eos_token_id=eos_token_id,
max_new_tokens=max_new_tokens,
temperature=temperature,
top_p=top_p,
use_cache=use_cache,
do_sample=do_sample,
streamer=streamer,
)
tokens = []
for t in output:
if streamer is None:
tokens.append(t[:, -1:])
if tokens:
result = torch.cat(tokens, dim=1)
full_sequence = torch.cat([input_ids_i, result], dim=1)
else:
full_sequence = input_ids_i
generated.append(full_sequence)
max_len = max(seq.shape[1] for seq in generated)
generated = [
torch.cat([
seq,
torch.full((1, max_len - seq.shape[1]), pad_token_id, dtype=seq.dtype, device=seq.device)
], dim=1)
for seq in generated
]
return torch.cat(generated, dim=0)
def _stream(
self,
input_ids: torch.LongTensor,
pixel_values: Optional[torch.FloatTensor] = None,
eos_token_id: Optional[int] = 2,
max_new_tokens: int = 128,
temperature: float = 1.0,
top_p: float = 1.0,
do_sample: bool = False,
streamer=None,
use_cache: bool = True,
**kwargs
):
past_key_values = None
first_pass = True
start_pos = input_ids.shape[1]
for _ in range(max_new_tokens):
if first_pass:
out = self(
input_ids=input_ids,
pixel_values=pixel_values,
past_key_values=None,
use_cache=use_cache,
**kwargs
)
first_pass = False
else:
out = self(
input_ids=input_ids[:, -1:], # only last token
past_key_values=past_key_values,
use_cache=use_cache,
**kwargs
)
logits = out.logits[:, -1, :]
past_key_values = out.past_key_values
if do_sample:
next_token = self.sample_logits(logits)
else:
next_token = torch.argmax(logits, dim=-1, keepdim=True)
input_ids = torch.cat([input_ids, next_token], dim=1)
if streamer is not None:
streamer.put(next_token)
yield input_ids[:, start_pos:]
if next_token.item() == eos_token_id:
break