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Resume/ultralytics/models/yolo/detect/val.py
2025-11-08 19:15:39 +01:00

496 lines
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Python

# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license
from __future__ import annotations
import os
from pathlib import Path
from typing import Any
import numpy as np
import torch
from ultralytics.data import build_dataloader, build_yolo_dataset, converter
from ultralytics.engine.validator import BaseValidator
from ultralytics.utils import LOGGER, nms, ops
from ultralytics.utils.checks import check_requirements
from ultralytics.utils.metrics import ConfusionMatrix, DetMetrics, box_iou
from ultralytics.utils.plotting import plot_images
class DetectionValidator(BaseValidator):
"""
A class extending the BaseValidator class for validation based on a detection model.
This class implements validation functionality specific to object detection tasks, including metrics calculation,
prediction processing, and visualization of results.
Attributes:
is_coco (bool): Whether the dataset is COCO.
is_lvis (bool): Whether the dataset is LVIS.
class_map (list[int]): Mapping from model class indices to dataset class indices.
metrics (DetMetrics): Object detection metrics calculator.
iouv (torch.Tensor): IoU thresholds for mAP calculation.
niou (int): Number of IoU thresholds.
lb (list[Any]): List for storing ground truth labels for hybrid saving.
jdict (list[dict[str, Any]]): List for storing JSON detection results.
stats (dict[str, list[torch.Tensor]]): Dictionary for storing statistics during validation.
Examples:
>>> from ultralytics.models.yolo.detect import DetectionValidator
>>> args = dict(model="yolo11n.pt", data="coco8.yaml")
>>> validator = DetectionValidator(args=args)
>>> validator()
"""
def __init__(self, dataloader=None, save_dir=None, args=None, _callbacks=None) -> None:
"""
Initialize detection validator with necessary variables and settings.
Args:
dataloader (torch.utils.data.DataLoader, optional): Dataloader to use for validation.
save_dir (Path, optional): Directory to save results.
args (dict[str, Any], optional): Arguments for the validator.
_callbacks (list[Any], optional): List of callback functions.
"""
super().__init__(dataloader, save_dir, args, _callbacks)
self.is_coco = False
self.is_lvis = False
self.class_map = None
self.args.task = "detect"
self.iouv = torch.linspace(0.5, 0.95, 10) # IoU vector for mAP@0.5:0.95
self.niou = self.iouv.numel()
self.metrics = DetMetrics()
def preprocess(self, batch: dict[str, Any]) -> dict[str, Any]:
"""
Preprocess batch of images for YOLO validation.
Args:
batch (dict[str, Any]): Batch containing images and annotations.
Returns:
(dict[str, Any]): Preprocessed batch.
"""
for k, v in batch.items():
if isinstance(v, torch.Tensor):
batch[k] = v.to(self.device, non_blocking=self.device.type == "cuda")
batch["img"] = (batch["img"].half() if self.args.half else batch["img"].float()) / 255
return batch
def init_metrics(self, model: torch.nn.Module) -> None:
"""
Initialize evaluation metrics for YOLO detection validation.
Args:
model (torch.nn.Module): Model to validate.
"""
val = self.data.get(self.args.split, "") # validation path
self.is_coco = (
isinstance(val, str)
and "coco" in val
and (val.endswith(f"{os.sep}val2017.txt") or val.endswith(f"{os.sep}test-dev2017.txt"))
) # is COCO
self.is_lvis = isinstance(val, str) and "lvis" in val and not self.is_coco # is LVIS
self.class_map = converter.coco80_to_coco91_class() if self.is_coco else list(range(1, len(model.names) + 1))
self.args.save_json |= self.args.val and (self.is_coco or self.is_lvis) and not self.training # run final val
self.names = model.names
self.nc = len(model.names)
self.end2end = getattr(model, "end2end", False)
self.seen = 0
self.jdict = []
self.metrics.names = model.names
self.confusion_matrix = ConfusionMatrix(names=model.names, save_matches=self.args.plots and self.args.visualize)
def get_desc(self) -> str:
"""Return a formatted string summarizing class metrics of YOLO model."""
return ("%22s" + "%11s" * 6) % ("Class", "Images", "Instances", "Box(P", "R", "mAP50", "mAP50-95)")
def postprocess(self, preds: torch.Tensor) -> list[dict[str, torch.Tensor]]:
"""
Apply Non-maximum suppression to prediction outputs.
Args:
preds (torch.Tensor): Raw predictions from the model.
Returns:
(list[dict[str, torch.Tensor]]): Processed predictions after NMS, where each dict contains
'bboxes', 'conf', 'cls', and 'extra' tensors.
"""
outputs = nms.non_max_suppression(
preds,
self.args.conf,
self.args.iou,
nc=0 if self.args.task == "detect" else self.nc,
multi_label=True,
agnostic=self.args.single_cls or self.args.agnostic_nms,
max_det=self.args.max_det,
end2end=self.end2end,
rotated=self.args.task == "obb",
)
return [{"bboxes": x[:, :4], "conf": x[:, 4], "cls": x[:, 5], "extra": x[:, 6:]} for x in outputs]
def _prepare_batch(self, si: int, batch: dict[str, Any]) -> dict[str, Any]:
"""
Prepare a batch of images and annotations for validation.
Args:
si (int): Batch index.
batch (dict[str, Any]): Batch data containing images and annotations.
Returns:
(dict[str, Any]): Prepared batch with processed annotations.
"""
idx = batch["batch_idx"] == si
cls = batch["cls"][idx].squeeze(-1)
bbox = batch["bboxes"][idx]
ori_shape = batch["ori_shape"][si]
imgsz = batch["img"].shape[2:]
ratio_pad = batch["ratio_pad"][si]
if cls.shape[0]:
bbox = ops.xywh2xyxy(bbox) * torch.tensor(imgsz, device=self.device)[[1, 0, 1, 0]] # target boxes
return {
"cls": cls,
"bboxes": bbox,
"ori_shape": ori_shape,
"imgsz": imgsz,
"ratio_pad": ratio_pad,
"im_file": batch["im_file"][si],
}
def _prepare_pred(self, pred: dict[str, torch.Tensor]) -> dict[str, torch.Tensor]:
"""
Prepare predictions for evaluation against ground truth.
Args:
pred (dict[str, torch.Tensor]): Post-processed predictions from the model.
Returns:
(dict[str, torch.Tensor]): Prepared predictions in native space.
"""
if self.args.single_cls:
pred["cls"] *= 0
return pred
def update_metrics(self, preds: list[dict[str, torch.Tensor]], batch: dict[str, Any]) -> None:
"""
Update metrics with new predictions and ground truth.
Args:
preds (list[dict[str, torch.Tensor]]): List of predictions from the model.
batch (dict[str, Any]): Batch data containing ground truth.
"""
for si, pred in enumerate(preds):
self.seen += 1
pbatch = self._prepare_batch(si, batch)
predn = self._prepare_pred(pred)
cls = pbatch["cls"].cpu().numpy()
no_pred = predn["cls"].shape[0] == 0
self.metrics.update_stats(
{
**self._process_batch(predn, pbatch),
"target_cls": cls,
"target_img": np.unique(cls),
"conf": np.zeros(0) if no_pred else predn["conf"].cpu().numpy(),
"pred_cls": np.zeros(0) if no_pred else predn["cls"].cpu().numpy(),
}
)
# Evaluate
if self.args.plots:
self.confusion_matrix.process_batch(predn, pbatch, conf=self.args.conf)
if self.args.visualize:
self.confusion_matrix.plot_matches(batch["img"][si], pbatch["im_file"], self.save_dir)
if no_pred:
continue
# Save
if self.args.save_json or self.args.save_txt:
predn_scaled = self.scale_preds(predn, pbatch)
if self.args.save_json:
self.pred_to_json(predn_scaled, pbatch)
if self.args.save_txt:
self.save_one_txt(
predn_scaled,
self.args.save_conf,
pbatch["ori_shape"],
self.save_dir / "labels" / f"{Path(pbatch['im_file']).stem}.txt",
)
def finalize_metrics(self) -> None:
"""Set final values for metrics speed and confusion matrix."""
if self.args.plots:
for normalize in True, False:
self.confusion_matrix.plot(save_dir=self.save_dir, normalize=normalize, on_plot=self.on_plot)
self.metrics.speed = self.speed
self.metrics.confusion_matrix = self.confusion_matrix
self.metrics.save_dir = self.save_dir
def get_stats(self) -> dict[str, Any]:
"""
Calculate and return metrics statistics.
Returns:
(dict[str, Any]): Dictionary containing metrics results.
"""
self.metrics.process(save_dir=self.save_dir, plot=self.args.plots, on_plot=self.on_plot)
self.metrics.clear_stats()
return self.metrics.results_dict
def print_results(self) -> None:
"""Print training/validation set metrics per class."""
pf = "%22s" + "%11i" * 2 + "%11.3g" * len(self.metrics.keys) # print format
LOGGER.info(pf % ("all", self.seen, self.metrics.nt_per_class.sum(), *self.metrics.mean_results()))
if self.metrics.nt_per_class.sum() == 0:
LOGGER.warning(f"no labels found in {self.args.task} set, can not compute metrics without labels")
# Print results per class
if self.args.verbose and not self.training and self.nc > 1 and len(self.metrics.stats):
for i, c in enumerate(self.metrics.ap_class_index):
LOGGER.info(
pf
% (
self.names[c],
self.metrics.nt_per_image[c],
self.metrics.nt_per_class[c],
*self.metrics.class_result(i),
)
)
def _process_batch(self, preds: dict[str, torch.Tensor], batch: dict[str, Any]) -> dict[str, np.ndarray]:
"""
Return correct prediction matrix.
Args:
preds (dict[str, torch.Tensor]): Dictionary containing prediction data with 'bboxes' and 'cls' keys.
batch (dict[str, Any]): Batch dictionary containing ground truth data with 'bboxes' and 'cls' keys.
Returns:
(dict[str, np.ndarray]): Dictionary containing 'tp' key with correct prediction matrix of shape (N, 10) for 10 IoU levels.
"""
if batch["cls"].shape[0] == 0 or preds["cls"].shape[0] == 0:
return {"tp": np.zeros((preds["cls"].shape[0], self.niou), dtype=bool)}
iou = box_iou(batch["bboxes"], preds["bboxes"])
return {"tp": self.match_predictions(preds["cls"], batch["cls"], iou).cpu().numpy()}
def build_dataset(self, img_path: str, mode: str = "val", batch: int | None = None) -> torch.utils.data.Dataset:
"""
Build YOLO Dataset.
Args:
img_path (str): Path to the folder containing images.
mode (str): `train` mode or `val` mode, users are able to customize different augmentations for each mode.
batch (int, optional): Size of batches, this is for `rect`.
Returns:
(Dataset): YOLO dataset.
"""
return build_yolo_dataset(self.args, img_path, batch, self.data, mode=mode, stride=self.stride)
def get_dataloader(self, dataset_path: str, batch_size: int) -> torch.utils.data.DataLoader:
"""
Construct and return dataloader.
Args:
dataset_path (str): Path to the dataset.
batch_size (int): Size of each batch.
Returns:
(torch.utils.data.DataLoader): Dataloader for validation.
"""
dataset = self.build_dataset(dataset_path, batch=batch_size, mode="val")
return build_dataloader(
dataset, batch_size, self.args.workers, shuffle=False, rank=-1, drop_last=self.args.compile
)
def plot_val_samples(self, batch: dict[str, Any], ni: int) -> None:
"""
Plot validation image samples.
Args:
batch (dict[str, Any]): Batch containing images and annotations.
ni (int): Batch index.
"""
plot_images(
labels=batch,
paths=batch["im_file"],
fname=self.save_dir / f"val_batch{ni}_labels.jpg",
names=self.names,
on_plot=self.on_plot,
)
def plot_predictions(
self, batch: dict[str, Any], preds: list[dict[str, torch.Tensor]], ni: int, max_det: int | None = None
) -> None:
"""
Plot predicted bounding boxes on input images and save the result.
Args:
batch (dict[str, Any]): Batch containing images and annotations.
preds (list[dict[str, torch.Tensor]]): List of predictions from the model.
ni (int): Batch index.
max_det (Optional[int]): Maximum number of detections to plot.
"""
# TODO: optimize this
for i, pred in enumerate(preds):
pred["batch_idx"] = torch.ones_like(pred["conf"]) * i # add batch index to predictions
keys = preds[0].keys()
max_det = max_det or self.args.max_det
batched_preds = {k: torch.cat([x[k][:max_det] for x in preds], dim=0) for k in keys}
# TODO: fix this
batched_preds["bboxes"][:, :4] = ops.xyxy2xywh(batched_preds["bboxes"][:, :4]) # convert to xywh format
plot_images(
images=batch["img"],
labels=batched_preds,
paths=batch["im_file"],
fname=self.save_dir / f"val_batch{ni}_pred.jpg",
names=self.names,
on_plot=self.on_plot,
) # pred
def save_one_txt(self, predn: dict[str, torch.Tensor], save_conf: bool, shape: tuple[int, int], file: Path) -> None:
"""
Save YOLO detections to a txt file in normalized coordinates in a specific format.
Args:
predn (dict[str, torch.Tensor]): Dictionary containing predictions with keys 'bboxes', 'conf', and 'cls'.
save_conf (bool): Whether to save confidence scores.
shape (tuple[int, int]): Shape of the original image (height, width).
file (Path): File path to save the detections.
"""
from ultralytics.engine.results import Results
Results(
np.zeros((shape[0], shape[1]), dtype=np.uint8),
path=None,
names=self.names,
boxes=torch.cat([predn["bboxes"], predn["conf"].unsqueeze(-1), predn["cls"].unsqueeze(-1)], dim=1),
).save_txt(file, save_conf=save_conf)
def pred_to_json(self, predn: dict[str, torch.Tensor], pbatch: dict[str, Any]) -> None:
"""
Serialize YOLO predictions to COCO json format.
Args:
predn (dict[str, torch.Tensor]): Predictions dictionary containing 'bboxes', 'conf', and 'cls' keys
with bounding box coordinates, confidence scores, and class predictions.
pbatch (dict[str, Any]): Batch dictionary containing 'imgsz', 'ori_shape', 'ratio_pad', and 'im_file'.
Examples:
>>> result = {
... "image_id": 42,
... "file_name": "42.jpg",
... "category_id": 18,
... "bbox": [258.15, 41.29, 348.26, 243.78],
... "score": 0.236,
... }
"""
path = Path(pbatch["im_file"])
stem = path.stem
image_id = int(stem) if stem.isnumeric() else stem
box = ops.xyxy2xywh(predn["bboxes"]) # xywh
box[:, :2] -= box[:, 2:] / 2 # xy center to top-left corner
for b, s, c in zip(box.tolist(), predn["conf"].tolist(), predn["cls"].tolist()):
self.jdict.append(
{
"image_id": image_id,
"file_name": path.name,
"category_id": self.class_map[int(c)],
"bbox": [round(x, 3) for x in b],
"score": round(s, 5),
}
)
def scale_preds(self, predn: dict[str, torch.Tensor], pbatch: dict[str, Any]) -> dict[str, torch.Tensor]:
"""Scales predictions to the original image size."""
return {
**predn,
"bboxes": ops.scale_boxes(
pbatch["imgsz"],
predn["bboxes"].clone(),
pbatch["ori_shape"],
ratio_pad=pbatch["ratio_pad"],
),
}
def eval_json(self, stats: dict[str, Any]) -> dict[str, Any]:
"""
Evaluate YOLO output in JSON format and return performance statistics.
Args:
stats (dict[str, Any]): Current statistics dictionary.
Returns:
(dict[str, Any]): Updated statistics dictionary with COCO/LVIS evaluation results.
"""
pred_json = self.save_dir / "predictions.json" # predictions
anno_json = (
self.data["path"]
/ "annotations"
/ ("instances_val2017.json" if self.is_coco else f"lvis_v1_{self.args.split}.json")
) # annotations
return self.coco_evaluate(stats, pred_json, anno_json)
def coco_evaluate(
self,
stats: dict[str, Any],
pred_json: str,
anno_json: str,
iou_types: str | list[str] = "bbox",
suffix: str | list[str] = "Box",
) -> dict[str, Any]:
"""
Evaluate COCO/LVIS metrics using faster-coco-eval library.
Performs evaluation using the faster-coco-eval library to compute mAP metrics
for object detection. Updates the provided stats dictionary with computed metrics
including mAP50, mAP50-95, and LVIS-specific metrics if applicable.
Args:
stats (dict[str, Any]): Dictionary to store computed metrics and statistics.
pred_json (str | Path]): Path to JSON file containing predictions in COCO format.
anno_json (str | Path]): Path to JSON file containing ground truth annotations in COCO format.
iou_types (str | list[str]]): IoU type(s) for evaluation. Can be single string or list of strings.
Common values include "bbox", "segm", "keypoints". Defaults to "bbox".
suffix (str | list[str]]): Suffix to append to metric names in stats dictionary. Should correspond
to iou_types if multiple types provided. Defaults to "Box".
Returns:
(dict[str, Any]): Updated stats dictionary containing the computed COCO/LVIS evaluation metrics.
"""
if self.args.save_json and (self.is_coco or self.is_lvis) and len(self.jdict):
LOGGER.info(f"\nEvaluating faster-coco-eval mAP using {pred_json} and {anno_json}...")
try:
for x in pred_json, anno_json:
assert x.is_file(), f"{x} file not found"
iou_types = [iou_types] if isinstance(iou_types, str) else iou_types
suffix = [suffix] if isinstance(suffix, str) else suffix
check_requirements("faster-coco-eval>=1.6.7")
from faster_coco_eval import COCO, COCOeval_faster
anno = COCO(anno_json)
pred = anno.loadRes(pred_json)
for i, iou_type in enumerate(iou_types):
val = COCOeval_faster(
anno, pred, iouType=iou_type, lvis_style=self.is_lvis, print_function=LOGGER.info
)
val.params.imgIds = [int(Path(x).stem) for x in self.dataloader.dataset.im_files] # images to eval
val.evaluate()
val.accumulate()
val.summarize()
# update mAP50-95 and mAP50
stats[f"metrics/mAP50({suffix[i][0]})"] = val.stats_as_dict["AP_50"]
stats[f"metrics/mAP50-95({suffix[i][0]})"] = val.stats_as_dict["AP_all"]
if self.is_lvis:
stats[f"metrics/APr({suffix[i][0]})"] = val.stats_as_dict["APr"]
stats[f"metrics/APc({suffix[i][0]})"] = val.stats_as_dict["APc"]
stats[f"metrics/APf({suffix[i][0]})"] = val.stats_as_dict["APf"]
if self.is_lvis:
stats["fitness"] = stats["metrics/mAP50-95(B)"] # always use box mAP50-95 for fitness
except Exception as e:
LOGGER.warning(f"faster-coco-eval unable to run: {e}")
return stats