286 lines
11 KiB
Python
286 lines
11 KiB
Python
|
# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
|
||
|
|
||
|
import os
|
||
|
import random
|
||
|
from pathlib import Path
|
||
|
from typing import Any, Iterator
|
||
|
|
||
|
import numpy as np
|
||
|
import torch
|
||
|
from PIL import Image
|
||
|
from torch.utils.data import dataloader, distributed
|
||
|
|
||
|
from ultralytics.data.dataset import GroundingDataset, YOLODataset, YOLOMultiModalDataset
|
||
|
from ultralytics.data.loaders import (
|
||
|
LOADERS,
|
||
|
LoadImagesAndVideos,
|
||
|
LoadPilAndNumpy,
|
||
|
LoadScreenshots,
|
||
|
LoadStreams,
|
||
|
LoadTensor,
|
||
|
SourceTypes,
|
||
|
autocast_list,
|
||
|
)
|
||
|
from ultralytics.data.utils import IMG_FORMATS, PIN_MEMORY, VID_FORMATS
|
||
|
from ultralytics.utils import RANK, colorstr
|
||
|
from ultralytics.utils.checks import check_file
|
||
|
|
||
|
|
||
|
class InfiniteDataLoader(dataloader.DataLoader):
|
||
|
"""
|
||
|
Dataloader that reuses workers for infinite iteration.
|
||
|
|
||
|
This dataloader extends the PyTorch DataLoader to provide infinite recycling of workers, which improves efficiency
|
||
|
for training loops that need to iterate through the dataset multiple times without recreating workers.
|
||
|
|
||
|
Attributes:
|
||
|
batch_sampler (_RepeatSampler): A sampler that repeats indefinitely.
|
||
|
iterator (Iterator): The iterator from the parent DataLoader.
|
||
|
|
||
|
Methods:
|
||
|
__len__: Return the length of the batch sampler's sampler.
|
||
|
__iter__: Create a sampler that repeats indefinitely.
|
||
|
__del__: Ensure workers are properly terminated.
|
||
|
reset: Reset the iterator, useful when modifying dataset settings during training.
|
||
|
|
||
|
Examples:
|
||
|
Create an infinite dataloader for training
|
||
|
>>> dataset = YOLODataset(...)
|
||
|
>>> dataloader = InfiniteDataLoader(dataset, batch_size=16, shuffle=True)
|
||
|
>>> for batch in dataloader: # Infinite iteration
|
||
|
>>> train_step(batch)
|
||
|
"""
|
||
|
|
||
|
def __init__(self, *args: Any, **kwargs: Any):
|
||
|
"""Initialize the InfiniteDataLoader with the same arguments as DataLoader."""
|
||
|
super().__init__(*args, **kwargs)
|
||
|
object.__setattr__(self, "batch_sampler", _RepeatSampler(self.batch_sampler))
|
||
|
self.iterator = super().__iter__()
|
||
|
|
||
|
def __len__(self) -> int:
|
||
|
"""Return the length of the batch sampler's sampler."""
|
||
|
return len(self.batch_sampler.sampler)
|
||
|
|
||
|
def __iter__(self) -> Iterator:
|
||
|
"""Create an iterator that yields indefinitely from the underlying iterator."""
|
||
|
for _ in range(len(self)):
|
||
|
yield next(self.iterator)
|
||
|
|
||
|
def __del__(self):
|
||
|
"""Ensure that workers are properly terminated when the dataloader is deleted."""
|
||
|
try:
|
||
|
if not hasattr(self.iterator, "_workers"):
|
||
|
return
|
||
|
for w in self.iterator._workers: # force terminate
|
||
|
if w.is_alive():
|
||
|
w.terminate()
|
||
|
self.iterator._shutdown_workers() # cleanup
|
||
|
except Exception:
|
||
|
pass
|
||
|
|
||
|
def reset(self):
|
||
|
"""Reset the iterator to allow modifications to the dataset during training."""
|
||
|
self.iterator = self._get_iterator()
|
||
|
|
||
|
|
||
|
class _RepeatSampler:
|
||
|
"""
|
||
|
Sampler that repeats forever for infinite iteration.
|
||
|
|
||
|
This sampler wraps another sampler and yields its contents indefinitely, allowing for infinite iteration
|
||
|
over a dataset without recreating the sampler.
|
||
|
|
||
|
Attributes:
|
||
|
sampler (Dataset.sampler): The sampler to repeat.
|
||
|
"""
|
||
|
|
||
|
def __init__(self, sampler: Any):
|
||
|
"""Initialize the _RepeatSampler with a sampler to repeat indefinitely."""
|
||
|
self.sampler = sampler
|
||
|
|
||
|
def __iter__(self) -> Iterator:
|
||
|
"""Iterate over the sampler indefinitely, yielding its contents."""
|
||
|
while True:
|
||
|
yield from iter(self.sampler)
|
||
|
|
||
|
|
||
|
def seed_worker(worker_id: int): # noqa
|
||
|
"""Set dataloader worker seed for reproducibility across worker processes."""
|
||
|
worker_seed = torch.initial_seed() % 2**32
|
||
|
np.random.seed(worker_seed)
|
||
|
random.seed(worker_seed)
|
||
|
|
||
|
|
||
|
def build_yolo_dataset(cfg, img_path, batch, data, mode="train", rect=False, stride=32, multi_modal=False):
|
||
|
"""Build and return a YOLO dataset based on configuration parameters."""
|
||
|
dataset = YOLOMultiModalDataset if multi_modal else YOLODataset
|
||
|
return dataset(
|
||
|
img_path=img_path,
|
||
|
imgsz=cfg.imgsz,
|
||
|
batch_size=batch,
|
||
|
augment=mode == "train", # augmentation
|
||
|
hyp=cfg, # TODO: probably add a get_hyps_from_cfg function
|
||
|
rect=cfg.rect or rect, # rectangular batches
|
||
|
cache=cfg.cache or None,
|
||
|
single_cls=cfg.single_cls or False,
|
||
|
stride=int(stride),
|
||
|
pad=0.0 if mode == "train" else 0.5,
|
||
|
prefix=colorstr(f"{mode}: "),
|
||
|
task=cfg.task,
|
||
|
classes=cfg.classes,
|
||
|
data=data,
|
||
|
fraction=cfg.fraction if mode == "train" else 1.0,
|
||
|
)
|
||
|
|
||
|
|
||
|
def build_grounding(cfg, img_path, json_file, batch, mode="train", rect=False, stride=32):
|
||
|
"""Build and return a GroundingDataset based on configuration parameters."""
|
||
|
return GroundingDataset(
|
||
|
img_path=img_path,
|
||
|
json_file=json_file,
|
||
|
imgsz=cfg.imgsz,
|
||
|
batch_size=batch,
|
||
|
augment=mode == "train", # augmentation
|
||
|
hyp=cfg, # TODO: probably add a get_hyps_from_cfg function
|
||
|
rect=cfg.rect or rect, # rectangular batches
|
||
|
cache=cfg.cache or None,
|
||
|
single_cls=cfg.single_cls or False,
|
||
|
stride=int(stride),
|
||
|
pad=0.0 if mode == "train" else 0.5,
|
||
|
prefix=colorstr(f"{mode}: "),
|
||
|
task=cfg.task,
|
||
|
classes=cfg.classes,
|
||
|
fraction=cfg.fraction if mode == "train" else 1.0,
|
||
|
)
|
||
|
|
||
|
|
||
|
def build_dataloader(dataset, batch: int, workers: int, shuffle: bool = True, rank: int = -1, drop_last: bool = False):
|
||
|
"""
|
||
|
Create and return an InfiniteDataLoader or DataLoader for training or validation.
|
||
|
|
||
|
Args:
|
||
|
dataset (Dataset): Dataset to load data from.
|
||
|
batch (int): Batch size for the dataloader.
|
||
|
workers (int): Number of worker threads for loading data.
|
||
|
shuffle (bool, optional): Whether to shuffle the dataset.
|
||
|
rank (int, optional): Process rank in distributed training. -1 for single-GPU training.
|
||
|
drop_last (bool, optional): Whether to drop the last incomplete batch.
|
||
|
|
||
|
Returns:
|
||
|
(InfiniteDataLoader): A dataloader that can be used for training or validation.
|
||
|
|
||
|
Examples:
|
||
|
Create a dataloader for training
|
||
|
>>> dataset = YOLODataset(...)
|
||
|
>>> dataloader = build_dataloader(dataset, batch=16, workers=4, shuffle=True)
|
||
|
"""
|
||
|
batch = min(batch, len(dataset))
|
||
|
nd = torch.cuda.device_count() # number of CUDA devices
|
||
|
nw = min(os.cpu_count() // max(nd, 1), workers) # number of workers
|
||
|
sampler = None if rank == -1 else distributed.DistributedSampler(dataset, shuffle=shuffle)
|
||
|
generator = torch.Generator()
|
||
|
generator.manual_seed(6148914691236517205 + RANK)
|
||
|
return InfiniteDataLoader(
|
||
|
dataset=dataset,
|
||
|
batch_size=batch,
|
||
|
shuffle=shuffle and sampler is None,
|
||
|
num_workers=nw,
|
||
|
sampler=sampler,
|
||
|
pin_memory=PIN_MEMORY,
|
||
|
collate_fn=getattr(dataset, "collate_fn", None),
|
||
|
worker_init_fn=seed_worker,
|
||
|
generator=generator,
|
||
|
drop_last=drop_last,
|
||
|
)
|
||
|
|
||
|
|
||
|
def check_source(source):
|
||
|
"""
|
||
|
Check the type of input source and return corresponding flag values.
|
||
|
|
||
|
Args:
|
||
|
source (str | int | Path | list | tuple | np.ndarray | PIL.Image | torch.Tensor): The input source to check.
|
||
|
|
||
|
Returns:
|
||
|
source (str | int | Path | list | tuple | np.ndarray | PIL.Image | torch.Tensor): The processed source.
|
||
|
webcam (bool): Whether the source is a webcam.
|
||
|
screenshot (bool): Whether the source is a screenshot.
|
||
|
from_img (bool): Whether the source is an image or list of images.
|
||
|
in_memory (bool): Whether the source is an in-memory object.
|
||
|
tensor (bool): Whether the source is a torch.Tensor.
|
||
|
|
||
|
Examples:
|
||
|
Check a file path source
|
||
|
>>> source, webcam, screenshot, from_img, in_memory, tensor = check_source("image.jpg")
|
||
|
|
||
|
Check a webcam source
|
||
|
>>> source, webcam, screenshot, from_img, in_memory, tensor = check_source(0)
|
||
|
"""
|
||
|
webcam, screenshot, from_img, in_memory, tensor = False, False, False, False, False
|
||
|
if isinstance(source, (str, int, Path)): # int for local usb camera
|
||
|
source = str(source)
|
||
|
source_lower = source.lower()
|
||
|
is_file = source_lower.rpartition(".")[-1] in (IMG_FORMATS | VID_FORMATS)
|
||
|
is_url = source_lower.startswith(("https://", "http://", "rtsp://", "rtmp://", "tcp://"))
|
||
|
webcam = source.isnumeric() or source.endswith(".streams") or (is_url and not is_file)
|
||
|
screenshot = source_lower == "screen"
|
||
|
if is_url and is_file:
|
||
|
source = check_file(source) # download
|
||
|
elif isinstance(source, LOADERS):
|
||
|
in_memory = True
|
||
|
elif isinstance(source, (list, tuple)):
|
||
|
source = autocast_list(source) # convert all list elements to PIL or np arrays
|
||
|
from_img = True
|
||
|
elif isinstance(source, (Image.Image, np.ndarray)):
|
||
|
from_img = True
|
||
|
elif isinstance(source, torch.Tensor):
|
||
|
tensor = True
|
||
|
else:
|
||
|
raise TypeError("Unsupported image type. For supported types see https://docs.ultralytics.com/modes/predict")
|
||
|
|
||
|
return source, webcam, screenshot, from_img, in_memory, tensor
|
||
|
|
||
|
|
||
|
def load_inference_source(source=None, batch: int = 1, vid_stride: int = 1, buffer: bool = False, channels: int = 3):
|
||
|
"""
|
||
|
Load an inference source for object detection and apply necessary transformations.
|
||
|
|
||
|
Args:
|
||
|
source (str | Path | torch.Tensor | PIL.Image | np.ndarray, optional): The input source for inference.
|
||
|
batch (int, optional): Batch size for dataloaders.
|
||
|
vid_stride (int, optional): The frame interval for video sources.
|
||
|
buffer (bool, optional): Whether stream frames will be buffered.
|
||
|
channels (int, optional): The number of input channels for the model.
|
||
|
|
||
|
Returns:
|
||
|
(Dataset): A dataset object for the specified input source with attached source_type attribute.
|
||
|
|
||
|
Examples:
|
||
|
Load an image source for inference
|
||
|
>>> dataset = load_inference_source("image.jpg", batch=1)
|
||
|
|
||
|
Load a video stream source
|
||
|
>>> dataset = load_inference_source("rtsp://example.com/stream", vid_stride=2)
|
||
|
"""
|
||
|
source, stream, screenshot, from_img, in_memory, tensor = check_source(source)
|
||
|
source_type = source.source_type if in_memory else SourceTypes(stream, screenshot, from_img, tensor)
|
||
|
|
||
|
# Dataloader
|
||
|
if tensor:
|
||
|
dataset = LoadTensor(source)
|
||
|
elif in_memory:
|
||
|
dataset = source
|
||
|
elif stream:
|
||
|
dataset = LoadStreams(source, vid_stride=vid_stride, buffer=buffer, channels=channels)
|
||
|
elif screenshot:
|
||
|
dataset = LoadScreenshots(source, channels=channels)
|
||
|
elif from_img:
|
||
|
dataset = LoadPilAndNumpy(source, channels=channels)
|
||
|
else:
|
||
|
dataset = LoadImagesAndVideos(source, batch=batch, vid_stride=vid_stride, channels=channels)
|
||
|
|
||
|
# Attach source types to the dataset
|
||
|
setattr(dataset, "source_type", source_type)
|
||
|
|
||
|
return dataset
|