dino-clips / dino /main_dino.py
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# Copyright (c) Facebook, Inc. and its affiliates.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import argparse
import os
import sys
import datetime
import time
import math
import json
from pathlib import Path
import numpy as np
from PIL import Image
import torch
import torch.nn as nn
import torch.distributed as dist
import torch.backends.cudnn as cudnn
import torch.nn.functional as F
from torchvision import datasets, transforms
from torchvision import models as torchvision_models
import utils
import vision_transformer as vits
from vision_transformer import DINOHead
torchvision_archs = sorted(name for name in torchvision_models.__dict__
if name.islower() and not name.startswith("__")
and callable(torchvision_models.__dict__[name]))
def get_args_parser():
parser = argparse.ArgumentParser('DINO', add_help=False)
# Model parameters
parser.add_argument('--arch', default='vit_small', type=str,
choices=['vit_tiny', 'vit_small', 'vit_base', 'xcit', 'deit_tiny', 'deit_small'] \
+ torchvision_archs + torch.hub.list("facebookresearch/xcit"),
help="""Name of architecture to train. For quick experiments with ViTs,
we recommend using vit_tiny or vit_small.""")
parser.add_argument('--patch_size', default=16, type=int, help="""Size in pixels
of input square patches - default 16 (for 16x16 patches). Using smaller
values leads to better performance but requires more memory. Applies only
for ViTs (vit_tiny, vit_small and vit_base). If <16, we recommend disabling
mixed precision training (--use_fp16 false) to avoid unstabilities.""")
parser.add_argument('--out_dim', default=65536, type=int, help="""Dimensionality of
the DINO head output. For complex and large datasets large values (like 65k) work well.""")
parser.add_argument('--norm_last_layer', default=True, type=utils.bool_flag,
help="""Whether or not to weight normalize the last layer of the DINO head.
Not normalizing leads to better performance but can make the training unstable.
In our experiments, we typically set this paramater to False with vit_small and True with vit_base.""")
parser.add_argument('--momentum_teacher', default=0.996, type=float, help="""Base EMA
parameter for teacher update. The value is increased to 1 during training with cosine schedule.
We recommend setting a higher value with small batches: for example use 0.9995 with batch size of 256.""")
parser.add_argument('--use_bn_in_head', default=False, type=utils.bool_flag,
help="Whether to use batch normalizations in projection head (Default: False)")
# Temperature teacher parameters
parser.add_argument('--warmup_teacher_temp', default=0.04, type=float,
help="""Initial value for the teacher temperature: 0.04 works well in most cases.
Try decreasing it if the training loss does not decrease.""")
parser.add_argument('--teacher_temp', default=0.04, type=float, help="""Final value (after linear warmup)
of the teacher temperature. For most experiments, anything above 0.07 is unstable. We recommend
starting with the default value of 0.04 and increase this slightly if needed.""")
parser.add_argument('--warmup_teacher_temp_epochs', default=0, type=int,
help='Number of warmup epochs for the teacher temperature (Default: 30).')
# Training/Optimization parameters
parser.add_argument('--use_fp16', type=utils.bool_flag, default=True, help="""Whether or not
to use half precision for training. Improves training time and memory requirements,
but can provoke instability and slight decay of performance. We recommend disabling
mixed precision if the loss is unstable, if reducing the patch size or if training with bigger ViTs.""")
parser.add_argument('--weight_decay', type=float, default=0.04, help="""Initial value of the
weight decay. With ViT, a smaller value at the beginning of training works well.""")
parser.add_argument('--weight_decay_end', type=float, default=0.4, help="""Final value of the
weight decay. We use a cosine schedule for WD and using a larger decay by
the end of training improves performance for ViTs.""")
parser.add_argument('--clip_grad', type=float, default=3.0, help="""Maximal parameter
gradient norm if using gradient clipping. Clipping with norm .3 ~ 1.0 can
help optimization for larger ViT architectures. 0 for disabling.""")
parser.add_argument('--batch_size_per_gpu', default=64, type=int,
help='Per-GPU batch-size : number of distinct images loaded on one GPU.')
parser.add_argument('--epochs', default=100, type=int, help='Number of epochs of training.')
parser.add_argument('--freeze_last_layer', default=1, type=int, help="""Number of epochs
during which we keep the output layer fixed. Typically doing so during
the first epoch helps training. Try increasing this value if the loss does not decrease.""")
parser.add_argument("--lr", default=0.0005, type=float, help="""Learning rate at the end of
linear warmup (highest LR used during training). The learning rate is linearly scaled
with the batch size, and specified here for a reference batch size of 256.""")
parser.add_argument("--warmup_epochs", default=10, type=int,
help="Number of epochs for the linear learning-rate warm up.")
parser.add_argument('--min_lr', type=float, default=1e-6, help="""Target LR at the
end of optimization. We use a cosine LR schedule with linear warmup.""")
parser.add_argument('--optimizer', default='adamw', type=str,
choices=['adamw', 'sgd', 'lars'], help="""Type of optimizer. We recommend using adamw with ViTs.""")
parser.add_argument('--drop_path_rate', type=float, default=0.1, help="stochastic depth rate")
# Multi-crop parameters
parser.add_argument('--global_crops_scale', type=float, nargs='+', default=(0.4, 1.),
help="""Scale range of the cropped image before resizing, relatively to the origin image.
Used for large global view cropping. When disabling multi-crop (--local_crops_number 0), we
recommand using a wider range of scale ("--global_crops_scale 0.14 1." for example)""")
parser.add_argument('--local_crops_number', type=int, default=8, help="""Number of small
local views to generate. Set this parameter to 0 to disable multi-crop training.
When disabling multi-crop we recommend to use "--global_crops_scale 0.14 1." """)
parser.add_argument('--local_crops_scale', type=float, nargs='+', default=(0.05, 0.4),
help="""Scale range of the cropped image before resizing, relatively to the origin image.
Used for small local view cropping of multi-crop.""")
# Misc
parser.add_argument('--data_path', default='/path/to/imagenet/train/', type=str,
help='Please specify path to the ImageNet training data.')
parser.add_argument('--output_dir', default=".", type=str, help='Path to save logs and checkpoints.')
parser.add_argument('--saveckp_freq', default=20, type=int, help='Save checkpoint every x epochs.')
parser.add_argument('--seed', default=0, type=int, help='Random seed.')
parser.add_argument('--num_workers', default=10, type=int, help='Number of data loading workers per GPU.')
parser.add_argument("--dist_url", default="env://", type=str, help="""url used to set up
distributed training; see https://pytorch.org/docs/stable/distributed.html""")
parser.add_argument("--local_rank", default=0, type=int, help="Please ignore and do not set this argument.")
return parser
def train_dino(args):
utils.init_distributed_mode(args)
utils.fix_random_seeds(args.seed)
print("git:\n {}\n".format(utils.get_sha()))
print("\n".join("%s: %s" % (k, str(v)) for k, v in sorted(dict(vars(args)).items())))
cudnn.benchmark = True
# ============ preparing data ... ============
transform = DataAugmentationDINO(
args.global_crops_scale,
args.local_crops_scale,
args.local_crops_number,
)
dataset = datasets.ImageFolder(args.data_path, transform=transform)
sampler = torch.utils.data.DistributedSampler(dataset, shuffle=True)
data_loader = torch.utils.data.DataLoader(
dataset,
sampler=sampler,
batch_size=args.batch_size_per_gpu,
num_workers=args.num_workers,
pin_memory=True,
drop_last=True,
)
print(f"Data loaded: there are {len(dataset)} images.")
# ============ building student and teacher networks ... ============
# we changed the name DeiT-S for ViT-S to avoid confusions
args.arch = args.arch.replace("deit", "vit")
# if the network is a Vision Transformer (i.e. vit_tiny, vit_small, vit_base)
if args.arch in vits.__dict__.keys():
student = vits.__dict__[args.arch](
patch_size=args.patch_size,
drop_path_rate=args.drop_path_rate, # stochastic depth
)
teacher = vits.__dict__[args.arch](patch_size=args.patch_size)
embed_dim = student.embed_dim
# if the network is a XCiT
elif args.arch in torch.hub.list("facebookresearch/xcit"):
student = torch.hub.load('facebookresearch/xcit', args.arch,
pretrained=False, drop_path_rate=args.drop_path_rate)
teacher = torch.hub.load('facebookresearch/xcit', args.arch, pretrained=False)
embed_dim = student.embed_dim
# otherwise, we check if the architecture is in torchvision models
elif args.arch in torchvision_models.__dict__.keys():
student = torchvision_models.__dict__[args.arch]()
teacher = torchvision_models.__dict__[args.arch]()
embed_dim = student.fc.weight.shape[1]
else:
print(f"Unknow architecture: {args.arch}")
# multi-crop wrapper handles forward with inputs of different resolutions
student = utils.MultiCropWrapper(student, DINOHead(
embed_dim,
args.out_dim,
use_bn=args.use_bn_in_head,
norm_last_layer=args.norm_last_layer,
))
teacher = utils.MultiCropWrapper(
teacher,
DINOHead(embed_dim, args.out_dim, args.use_bn_in_head),
)
# move networks to gpu
student, teacher = student.cuda(), teacher.cuda()
# synchronize batch norms (if any)
if utils.has_batchnorms(student):
student = nn.SyncBatchNorm.convert_sync_batchnorm(student)
teacher = nn.SyncBatchNorm.convert_sync_batchnorm(teacher)
# we need DDP wrapper to have synchro batch norms working...
teacher = nn.parallel.DistributedDataParallel(teacher, device_ids=[args.gpu])
teacher_without_ddp = teacher.module
else:
# teacher_without_ddp and teacher are the same thing
teacher_without_ddp = teacher
student = nn.parallel.DistributedDataParallel(student, device_ids=[args.gpu])
# teacher and student start with the same weights
teacher_without_ddp.load_state_dict(student.module.state_dict())
# there is no backpropagation through the teacher, so no need for gradients
for p in teacher.parameters():
p.requires_grad = False
print(f"Student and Teacher are built: they are both {args.arch} network.")
# ============ preparing loss ... ============
dino_loss = DINOLoss(
args.out_dim,
args.local_crops_number + 2, # total number of crops = 2 global crops + local_crops_number
args.warmup_teacher_temp,
args.teacher_temp,
args.warmup_teacher_temp_epochs,
args.epochs,
).cuda()
# ============ preparing optimizer ... ============
params_groups = utils.get_params_groups(student)
if args.optimizer == "adamw":
optimizer = torch.optim.AdamW(params_groups) # to use with ViTs
elif args.optimizer == "sgd":
optimizer = torch.optim.SGD(params_groups, lr=0, momentum=0.9) # lr is set by scheduler
elif args.optimizer == "lars":
optimizer = utils.LARS(params_groups) # to use with convnet and large batches
# for mixed precision training
fp16_scaler = None
if args.use_fp16:
fp16_scaler = torch.cuda.amp.GradScaler()
# ============ init schedulers ... ============
lr_schedule = utils.cosine_scheduler(
args.lr * (args.batch_size_per_gpu * utils.get_world_size()) / 256., # linear scaling rule
args.min_lr,
args.epochs, len(data_loader),
warmup_epochs=args.warmup_epochs,
)
wd_schedule = utils.cosine_scheduler(
args.weight_decay,
args.weight_decay_end,
args.epochs, len(data_loader),
)
# momentum parameter is increased to 1. during training with a cosine schedule
momentum_schedule = utils.cosine_scheduler(args.momentum_teacher, 1,
args.epochs, len(data_loader))
print(f"Loss, optimizer and schedulers ready.")
# ============ optionally resume training ... ============
to_restore = {"epoch": 0}
utils.restart_from_checkpoint(
os.path.join(args.output_dir, "checkpoint.pth"),
run_variables=to_restore,
student=student,
teacher=teacher,
optimizer=optimizer,
fp16_scaler=fp16_scaler,
dino_loss=dino_loss,
)
start_epoch = to_restore["epoch"]
start_time = time.time()
print("Starting DINO training !")
for epoch in range(start_epoch, args.epochs):
data_loader.sampler.set_epoch(epoch)
# ============ training one epoch of DINO ... ============
train_stats = train_one_epoch(student, teacher, teacher_without_ddp, dino_loss,
data_loader, optimizer, lr_schedule, wd_schedule, momentum_schedule,
epoch, fp16_scaler, args)
# ============ writing logs ... ============
save_dict = {
'student': student.state_dict(),
'teacher': teacher.state_dict(),
'optimizer': optimizer.state_dict(),
'epoch': epoch + 1,
'args': args,
'dino_loss': dino_loss.state_dict(),
}
if fp16_scaler is not None:
save_dict['fp16_scaler'] = fp16_scaler.state_dict()
utils.save_on_master(save_dict, os.path.join(args.output_dir, 'checkpoint.pth'))
if args.saveckp_freq and epoch % args.saveckp_freq == 0:
utils.save_on_master(save_dict, os.path.join(args.output_dir, f'checkpoint{epoch:04}.pth'))
log_stats = {**{f'train_{k}': v for k, v in train_stats.items()},
'epoch': epoch}
if utils.is_main_process():
with (Path(args.output_dir) / "log.txt").open("a") as f:
f.write(json.dumps(log_stats) + "\n")
total_time = time.time() - start_time
total_time_str = str(datetime.timedelta(seconds=int(total_time)))
print('Training time {}'.format(total_time_str))
def train_one_epoch(student, teacher, teacher_without_ddp, dino_loss, data_loader,
optimizer, lr_schedule, wd_schedule, momentum_schedule,epoch,
fp16_scaler, args):
metric_logger = utils.MetricLogger(delimiter=" ")
header = 'Epoch: [{}/{}]'.format(epoch, args.epochs)
for it, (images, _) in enumerate(metric_logger.log_every(data_loader, 10, header)):
# update weight decay and learning rate according to their schedule
it = len(data_loader) * epoch + it # global training iteration
for i, param_group in enumerate(optimizer.param_groups):
param_group["lr"] = lr_schedule[it]
if i == 0: # only the first group is regularized
param_group["weight_decay"] = wd_schedule[it]
# move images to gpu
images = [im.cuda(non_blocking=True) for im in images]
# teacher and student forward passes + compute dino loss
with torch.cuda.amp.autocast(fp16_scaler is not None):
teacher_output = teacher(images[:2]) # only the 2 global views pass through the teacher
student_output = student(images)
loss = dino_loss(student_output, teacher_output, epoch)
if not math.isfinite(loss.item()):
print("Loss is {}, stopping training".format(loss.item()), force=True)
sys.exit(1)
# student update
optimizer.zero_grad()
param_norms = None
if fp16_scaler is None:
loss.backward()
if args.clip_grad:
param_norms = utils.clip_gradients(student, args.clip_grad)
utils.cancel_gradients_last_layer(epoch, student,
args.freeze_last_layer)
optimizer.step()
else:
fp16_scaler.scale(loss).backward()
if args.clip_grad:
fp16_scaler.unscale_(optimizer) # unscale the gradients of optimizer's assigned params in-place
param_norms = utils.clip_gradients(student, args.clip_grad)
utils.cancel_gradients_last_layer(epoch, student,
args.freeze_last_layer)
fp16_scaler.step(optimizer)
fp16_scaler.update()
# EMA update for the teacher
with torch.no_grad():
m = momentum_schedule[it] # momentum parameter
for param_q, param_k in zip(student.module.parameters(), teacher_without_ddp.parameters()):
param_k.data.mul_(m).add_((1 - m) * param_q.detach().data)
# logging
torch.cuda.synchronize()
metric_logger.update(loss=loss.item())
metric_logger.update(lr=optimizer.param_groups[0]["lr"])
metric_logger.update(wd=optimizer.param_groups[0]["weight_decay"])
# gather the stats from all processes
metric_logger.synchronize_between_processes()
print("Averaged stats:", metric_logger)
return {k: meter.global_avg for k, meter in metric_logger.meters.items()}
class DINOLoss(nn.Module):
def __init__(self, out_dim, ncrops, warmup_teacher_temp, teacher_temp,
warmup_teacher_temp_epochs, nepochs, student_temp=0.1,
center_momentum=0.9):
super().__init__()
self.student_temp = student_temp
self.center_momentum = center_momentum
self.ncrops = ncrops
self.register_buffer("center", torch.zeros(1, out_dim))
# we apply a warm up for the teacher temperature because
# a too high temperature makes the training instable at the beginning
self.teacher_temp_schedule = np.concatenate((
np.linspace(warmup_teacher_temp,
teacher_temp, warmup_teacher_temp_epochs),
np.ones(nepochs - warmup_teacher_temp_epochs) * teacher_temp
))
def forward(self, student_output, teacher_output, epoch):
"""
Cross-entropy between softmax outputs of the teacher and student networks.
"""
student_out = student_output / self.student_temp
student_out = student_out.chunk(self.ncrops)
# teacher centering and sharpening
temp = self.teacher_temp_schedule[epoch]
teacher_out = F.softmax((teacher_output - self.center) / temp, dim=-1)
teacher_out = teacher_out.detach().chunk(2)
total_loss = 0
n_loss_terms = 0
for iq, q in enumerate(teacher_out):
for v in range(len(student_out)):
if v == iq:
# we skip cases where student and teacher operate on the same view
continue
loss = torch.sum(-q * F.log_softmax(student_out[v], dim=-1), dim=-1)
total_loss += loss.mean()
n_loss_terms += 1
total_loss /= n_loss_terms
self.update_center(teacher_output)
return total_loss
@torch.no_grad()
def update_center(self, teacher_output):
"""
Update center used for teacher output.
"""
batch_center = torch.sum(teacher_output, dim=0, keepdim=True)
dist.all_reduce(batch_center)
batch_center = batch_center / (len(teacher_output) * dist.get_world_size())
# ema update
self.center = self.center * self.center_momentum + batch_center * (1 - self.center_momentum)
class DataAugmentationDINO(object):
def __init__(self, global_crops_scale, local_crops_scale, local_crops_number):
flip_and_color_jitter = transforms.Compose([
transforms.RandomHorizontalFlip(p=0.5),
transforms.RandomApply(
[transforms.ColorJitter(brightness=0.4, contrast=0.4, saturation=0.2, hue=0.1)],
p=0.8
),
transforms.RandomGrayscale(p=0.2),
])
normalize = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.485, 0.456, 0.406), (0.229, 0.224, 0.225)),
])
# first global crop
self.global_transfo1 = transforms.Compose([
transforms.RandomResizedCrop(224, scale=global_crops_scale, interpolation=Image.BICUBIC),
flip_and_color_jitter,
utils.GaussianBlur(1.0),
normalize,
])
# second global crop
self.global_transfo2 = transforms.Compose([
transforms.RandomResizedCrop(224, scale=global_crops_scale, interpolation=Image.BICUBIC),
flip_and_color_jitter,
utils.GaussianBlur(0.1),
utils.Solarization(0.2),
normalize,
])
# transformation for the local small crops
self.local_crops_number = local_crops_number
self.local_transfo = transforms.Compose([
transforms.RandomResizedCrop(96, scale=local_crops_scale, interpolation=Image.BICUBIC),
flip_and_color_jitter,
utils.GaussianBlur(p=0.5),
normalize,
])
def __call__(self, image):
crops = []
crops.append(self.global_transfo1(image))
crops.append(self.global_transfo2(image))
for _ in range(self.local_crops_number):
crops.append(self.local_transfo(image))
return crops
if __name__ == '__main__':
parser = argparse.ArgumentParser('DINO', parents=[get_args_parser()])
args = parser.parse_args()
Path(args.output_dir).mkdir(parents=True, exist_ok=True)
train_dino(args)