Files
MiniCPM-o/finetune/dataset.py
2024-05-08 09:51:34 +08:00

291 lines
10 KiB
Python

import os
import math
import json
import copy
import logging
import numpy as np
import torch
from torch.nn.utils.rnn import pad_sequence
from typing import Dict, Optional, List
from PIL import Image
from dataclasses import dataclass, field
from transformers import AutoTokenizer, AutoProcessor
from torch.utils.data import Dataset
class SupervisedDataset(Dataset):
"""Dataset for supervised fine-tuning."""
def __init__(self, raw_data, transform, tokenizer, slice_config):
super(SupervisedDataset, self).__init__()
self.raw_data = raw_data
self.tokenizer = tokenizer
self.transform = transform
self.slice_config = slice_config
def __len__(self):
return len(self.raw_data)
def __getitem__(self, i) -> Dict[str, torch.Tensor]:
image = Image.open(self.raw_data[i]["image"]).convert("RGB")
ret = preprocess(image, self.raw_data[i]["conversations"], self.tokenizer, self.transform, slice_config=self.slice_config)
ret = dict(
input_ids=ret["input_ids"],
labels=ret["target"],
attention_mask=ret["input_ids"].ne(self.tokenizer.pad_token_id),
pixel_values=ret["pixel_values"],
image_bound=ret["image_bound"],
)
return ret
def data_collator(examples, padding_value=0):
input_ids = pad_sequence([example["input_ids"] for example in examples], batch_first=True, padding_value=padding_value)
targets = pad_sequence([example["labels"] for example in examples], batch_first=True, padding_value=padding_value)
attention_mask = pad_sequence([example["attention_mask"] for example in examples], batch_first=True, padding_value=padding_value)
pixel_values = [example["pixel_values"] for example in examples]
image_bound = [example["image_bound"] for example in examples]
return {"input_ids": input_ids, "labels":targets, "attention_mask": attention_mask, "image_bound": image_bound, "pixel_values": pixel_values}
def conversation_to_ids(conversation, tokenizer):
"""
for single image multi-turn conversation
conversation: [{'role': 'user', 'content': 'Describe this image'},
{'role': 'assistant', 'content': 'This is a cat.'}]
"""
raw_msg = ''
input_ids = []
context = []
for idx, msg in enumerate(conversation):
role = msg['role']
message = msg['content']
assert role in ['user', 'assistant']
if role == 'user':
prefix = '<用户>'
else:
prefix = '<AI>'
# append eos
if idx == len(conversation) - 1:
message = message + tokenizer.eos_token
prefix_ids = tokenizer.encode(prefix)[1:] # remove bos
message_ids = tokenizer.encode(message)[1:]
input_ids.append(prefix_ids)
input_ids.append(message_ids)
context.append(np.ones((len(prefix_ids),), dtype=np.int8))
if role == 'assistant':
context.append(np.zeros((len(message_ids),), dtype=np.int8))
else:
context.append(np.ones((len(message_ids),), dtype=np.int8))
raw_msg += (prefix + message)
ids = torch.from_numpy(np.hstack(input_ids, dtype=np.int32))
context = torch.from_numpy(np.hstack(context, dtype=np.int8))
# build target
target = torch.full_like(ids, -100, dtype=torch.int32)
for i in range(1, len(ids)):
if context[i] == 0:
target[i - 1] = ids[i]
if context[i] == 1 and context[i - 1] == 0:
target[i - 1] = tokenizer.eos_id
# build image bound
image_start_tokens = torch.where(ids == tokenizer.im_start_id)[0]
image_start_tokens += 1
image_end_tokens = torch.where(ids == tokenizer.im_end_id)[0]
if len(image_start_tokens) != len(image_end_tokens):
print('image start token != image end tokens')
if len(image_start_tokens)>0:
image_bound = torch.hstack([image_start_tokens.unsqueeze(-1), image_end_tokens.unsqueeze(-1)])
else:
image_bound = []
return {
'input_ids': ids,
'target': target,
'image_bound': image_bound,
'raw_msg': raw_msg,
}
def preprocess(image, conversation, tokenizer, transform, query_nums=64, slice_config=None):
"""
single image preprocess, the image will be placed at the top of the conversation
"""
conversation = copy.deepcopy(conversation)
assert len(conversation) > 1, "conversation length must large than 2"
assert conversation[0]['role'] == 'user', "the first role must be user"
if slice_config is not None:
assert isinstance(slice_config, Dict)
assert 'patch_size' in slice_config
assert 'max_slice_nums' in slice_config
assert 'scale_resolution' in slice_config
default_image_placeholder = tokenizer.im_start + tokenizer.unk_token * query_nums + tokenizer.im_end
if slice_config:
images = []
source_image, patches, best_grid = slice_image(
image, slice_config['max_slice_nums'], slice_config['scale_resolution'], slice_config['patch_size']
)
images.append(source_image)
image_placeholder = default_image_placeholder
if len(patches) > 0:
for i in range(len(patches)):
for j in range(len(patches[0])):
images.append(patches[i][j])
image_placeholder += get_grid_placeholder(
tokenizer, best_grid, query_nums
)
images = [transform(i) for i in images]
else:
images = [transform(image)]
image_placeholder = default_image_placeholder
if '<image>' in conversation[0]['content']:
conversation[0]['content'] = conversation[0]['content'].replace('<image>', image_placeholder)
else:
conversation[0]['content'] = image_placeholder + '\n' + conversation[0]['content']
input_dict = conversation_to_ids(conversation, tokenizer)
input_dict['pixel_values'] = images
return input_dict
def slice_image(
image, max_slice_nums=9, scale_resolution=448, patch_size=14, never_split=False
):
original_size = image.size
original_width, original_height = original_size
log_ratio = math.log(original_width / original_height)
ratio = original_width * original_height / (scale_resolution * scale_resolution)
multiple = min(math.ceil(ratio), max_slice_nums)
source_image = None
best_grid = None
patches = []
if multiple <= 1 or never_split:
# dont need to slice, upsample
best_size = find_best_resize(
original_size, scale_resolution, patch_size, allow_upscale=True
)
source_image = image.resize(best_size, Image.Resampling.BICUBIC)
else:
candidate_split_grids_nums = []
for i in [multiple - 1, multiple, multiple + 1]:
if i == 1 or i > max_slice_nums:
continue
candidate_split_grids_nums.append(i)
# source image, down-sampling and ensure divided by patch_size
best_resize = find_best_resize(original_size, scale_resolution, patch_size)
source_image = image.copy().resize(best_resize, Image.Resampling.BICUBIC)
candidate_grids = []
# find best grid
for split_grids_nums in candidate_split_grids_nums:
m = 1
while m <= split_grids_nums:
if split_grids_nums % m == 0:
candidate_grids.append([m, split_grids_nums // m])
m += 1
best_grid = [1, 1]
min_error = float("inf")
for grid in candidate_grids:
error = abs(log_ratio - math.log(grid[0] / grid[1]))
if error < min_error:
best_grid = grid
min_error = error
refine_size = get_refine_size(
original_size, best_grid, scale_resolution, patch_size, allow_upscale=True
)
refine_image = image.resize(refine_size, Image.Resampling.BICUBIC)
patches = split_to_patches(refine_image, best_grid)
return source_image, patches, best_grid
def ensure_divide(length, patch_size):
return max(round(length / patch_size) * patch_size, patch_size)
def find_best_resize(original_size, scale_resolution, patch_size, allow_upscale=False):
width, height = original_size
if (width * height > scale_resolution * scale_resolution) or allow_upscale:
r = width / height
height = int(scale_resolution / math.sqrt(r))
width = int(height * r)
best_width = ensure_divide(width, patch_size)
best_height = ensure_divide(height, patch_size)
return (best_width, best_height)
def get_refine_size(
original_size, grid, scale_resolution, patch_size, allow_upscale=False
):
width, height = original_size
grid_x, grid_y = grid
refine_width = ensure_divide(width, grid_x)
refine_height = ensure_divide(height, grid_y)
grid_width = refine_width / grid_x
grid_height = refine_height / grid_y
best_grid_size = find_best_resize(
(grid_width, grid_height),
scale_resolution,
patch_size,
allow_upscale=allow_upscale,
)
refine_size = (best_grid_size[0] * grid_x, best_grid_size[1] * grid_y)
return refine_size
def split_to_patches(image, grid):
patches = []
width, height = image.size
grid_x = int(width / grid[0])
grid_y = int(height / grid[1])
for i in range(0, height, grid_y):
images = []
for j in range(0, width, grid_x):
box = (j, i, j + grid_x, i + grid_y)
patch = image.crop(box)
images.append(patch)
patches.append(images)
return patches
def get_grid_placeholder(tokenizer, grid, query_num):
image_placeholder = (
tokenizer.im_start + tokenizer.unk_token * query_num + tokenizer.im_end
)
cols = grid[0]
rows = grid[1]
slices = []
for i in range(rows):
lines = []
for j in range(cols):
lines.append(image_placeholder)
slices.append("".join(lines))
slice_placeholder = tokenizer.slice_start + "\n".join(slices) + tokenizer.slice_end
return slice_placeholder