コンテンツへスキップ

参考 ultralytics/data/dataset.py

注

このファイルはhttps://github.com/ultralytics/ultralytics/blob/main/ ultralytics/data/dataset .py にあります。もし問題を発見したら、Pull Request🛠️ を投稿して修正にご協力ください。ありがとうございました!



ultralytics.data.dataset.YOLODataset

ベース: BaseDataset

YOLO 形式のオブジェクト検出および/またはセグメンテーションラベルをロードするためのデータセットクラス。

パラメーター

名称 タイプ 説明 デフォルト
data dict

データセットYAML辞書。デフォルトは None です。

None
task str

現在のタスクを指定する明示的な引数。

'detect'

リターンズ

タイプ 説明
Dataset

PyTorch オブジェクト検出モデルの学習に使用できるデータセットオブジェクト。

ソースコード ultralytics/data/dataset.py
class YOLODataset(BaseDataset):
    """
    Dataset class for loading object detection and/or segmentation labels in YOLO format.

    Args:
        data (dict, optional): A dataset YAML dictionary. Defaults to None.
        task (str): An explicit arg to point current task, Defaults to 'detect'.

    Returns:
        (torch.utils.data.Dataset): A PyTorch dataset object that can be used for training an object detection model.
    """

    def __init__(self, *args, data=None, task="detect", **kwargs):
        """Initializes the YOLODataset with optional configurations for segments and keypoints."""
        self.use_segments = task == "segment"
        self.use_keypoints = task == "pose"
        self.use_obb = task == "obb"
        self.data = data
        assert not (self.use_segments and self.use_keypoints), "Can not use both segments and keypoints."
        super().__init__(*args, **kwargs)

    def cache_labels(self, path=Path("./labels.cache")):
        """
        Cache dataset labels, check images and read shapes.

        Args:
            path (Path): Path where to save the cache file. Default is Path('./labels.cache').

        Returns:
            (dict): labels.
        """
        x = {"labels": []}
        nm, nf, ne, nc, msgs = 0, 0, 0, 0, []  # number missing, found, empty, corrupt, messages
        desc = f"{self.prefix}Scanning {path.parent / path.stem}..."
        total = len(self.im_files)
        nkpt, ndim = self.data.get("kpt_shape", (0, 0))
        if self.use_keypoints and (nkpt <= 0 or ndim not in {2, 3}):
            raise ValueError(
                "'kpt_shape' in data.yaml missing or incorrect. Should be a list with [number of "
                "keypoints, number of dims (2 for x,y or 3 for x,y,visible)], i.e. 'kpt_shape: [17, 3]'"
            )
        with ThreadPool(NUM_THREADS) as pool:
            results = pool.imap(
                func=verify_image_label,
                iterable=zip(
                    self.im_files,
                    self.label_files,
                    repeat(self.prefix),
                    repeat(self.use_keypoints),
                    repeat(len(self.data["names"])),
                    repeat(nkpt),
                    repeat(ndim),
                ),
            )
            pbar = TQDM(results, desc=desc, total=total)
            for im_file, lb, shape, segments, keypoint, nm_f, nf_f, ne_f, nc_f, msg in pbar:
                nm += nm_f
                nf += nf_f
                ne += ne_f
                nc += nc_f
                if im_file:
                    x["labels"].append(
                        {
                            "im_file": im_file,
                            "shape": shape,
                            "cls": lb[:, 0:1],  # n, 1
                            "bboxes": lb[:, 1:],  # n, 4
                            "segments": segments,
                            "keypoints": keypoint,
                            "normalized": True,
                            "bbox_format": "xywh",
                        }
                    )
                if msg:
                    msgs.append(msg)
                pbar.desc = f"{desc} {nf} images, {nm + ne} backgrounds, {nc} corrupt"
            pbar.close()

        if msgs:
            LOGGER.info("\n".join(msgs))
        if nf == 0:
            LOGGER.warning(f"{self.prefix}WARNING ⚠️ No labels found in {path}. {HELP_URL}")
        x["hash"] = get_hash(self.label_files + self.im_files)
        x["results"] = nf, nm, ne, nc, len(self.im_files)
        x["msgs"] = msgs  # warnings
        save_dataset_cache_file(self.prefix, path, x, DATASET_CACHE_VERSION)
        return x

    def get_labels(self):
        """Returns dictionary of labels for YOLO training."""
        self.label_files = img2label_paths(self.im_files)
        cache_path = Path(self.label_files[0]).parent.with_suffix(".cache")
        try:
            cache, exists = load_dataset_cache_file(cache_path), True  # attempt to load a *.cache file
            assert cache["version"] == DATASET_CACHE_VERSION  # matches current version
            assert cache["hash"] == get_hash(self.label_files + self.im_files)  # identical hash
        except (FileNotFoundError, AssertionError, AttributeError):
            cache, exists = self.cache_labels(cache_path), False  # run cache ops

        # Display cache
        nf, nm, ne, nc, n = cache.pop("results")  # found, missing, empty, corrupt, total
        if exists and LOCAL_RANK in {-1, 0}:
            d = f"Scanning {cache_path}... {nf} images, {nm + ne} backgrounds, {nc} corrupt"
            TQDM(None, desc=self.prefix + d, total=n, initial=n)  # display results
            if cache["msgs"]:
                LOGGER.info("\n".join(cache["msgs"]))  # display warnings

        # Read cache
        [cache.pop(k) for k in ("hash", "version", "msgs")]  # remove items
        labels = cache["labels"]
        if not labels:
            LOGGER.warning(f"WARNING ⚠️ No images found in {cache_path}, training may not work correctly. {HELP_URL}")
        self.im_files = [lb["im_file"] for lb in labels]  # update im_files

        # Check if the dataset is all boxes or all segments
        lengths = ((len(lb["cls"]), len(lb["bboxes"]), len(lb["segments"])) for lb in labels)
        len_cls, len_boxes, len_segments = (sum(x) for x in zip(*lengths))
        if len_segments and len_boxes != len_segments:
            LOGGER.warning(
                f"WARNING ⚠️ Box and segment counts should be equal, but got len(segments) = {len_segments}, "
                f"len(boxes) = {len_boxes}. To resolve this only boxes will be used and all segments will be removed. "
                "To avoid this please supply either a detect or segment dataset, not a detect-segment mixed dataset."
            )
            for lb in labels:
                lb["segments"] = []
        if len_cls == 0:
            LOGGER.warning(f"WARNING ⚠️ No labels found in {cache_path}, training may not work correctly. {HELP_URL}")
        return labels

    def build_transforms(self, hyp=None):
        """Builds and appends transforms to the list."""
        if self.augment:
            hyp.mosaic = hyp.mosaic if self.augment and not self.rect else 0.0
            hyp.mixup = hyp.mixup if self.augment and not self.rect else 0.0
            transforms = v8_transforms(self, self.imgsz, hyp)
        else:
            transforms = Compose([LetterBox(new_shape=(self.imgsz, self.imgsz), scaleup=False)])
        transforms.append(
            Format(
                bbox_format="xywh",
                normalize=True,
                return_mask=self.use_segments,
                return_keypoint=self.use_keypoints,
                return_obb=self.use_obb,
                batch_idx=True,
                mask_ratio=hyp.mask_ratio,
                mask_overlap=hyp.overlap_mask,
                bgr=hyp.bgr if self.augment else 0.0,  # only affect training.
            )
        )
        return transforms

    def close_mosaic(self, hyp):
        """Sets mosaic, copy_paste and mixup options to 0.0 and builds transformations."""
        hyp.mosaic = 0.0  # set mosaic ratio=0.0
        hyp.copy_paste = 0.0  # keep the same behavior as previous v8 close-mosaic
        hyp.mixup = 0.0  # keep the same behavior as previous v8 close-mosaic
        self.transforms = self.build_transforms(hyp)

    def update_labels_info(self, label):
        """
        Custom your label format here.

        Note:
            cls is not with bboxes now, classification and semantic segmentation need an independent cls label
            Can also support classification and semantic segmentation by adding or removing dict keys there.
        """
        bboxes = label.pop("bboxes")
        segments = label.pop("segments", [])
        keypoints = label.pop("keypoints", None)
        bbox_format = label.pop("bbox_format")
        normalized = label.pop("normalized")

        # NOTE: do NOT resample oriented boxes
        segment_resamples = 100 if self.use_obb else 1000
        if len(segments) > 0:
            # list[np.array(1000, 2)] * num_samples
            # (N, 1000, 2)
            segments = np.stack(resample_segments(segments, n=segment_resamples), axis=0)
        else:
            segments = np.zeros((0, segment_resamples, 2), dtype=np.float32)
        label["instances"] = Instances(bboxes, segments, keypoints, bbox_format=bbox_format, normalized=normalized)
        return label

    @staticmethod
    def collate_fn(batch):
        """Collates data samples into batches."""
        new_batch = {}
        keys = batch[0].keys()
        values = list(zip(*[list(b.values()) for b in batch]))
        for i, k in enumerate(keys):
            value = values[i]
            if k == "img":
                value = torch.stack(value, 0)
            if k in {"masks", "keypoints", "bboxes", "cls", "segments", "obb"}:
                value = torch.cat(value, 0)
            new_batch[k] = value
        new_batch["batch_idx"] = list(new_batch["batch_idx"])
        for i in range(len(new_batch["batch_idx"])):
            new_batch["batch_idx"][i] += i  # add target image index for build_targets()
        new_batch["batch_idx"] = torch.cat(new_batch["batch_idx"], 0)
        return new_batch

__init__(*args, data=None, task='detect', **kwargs)

YOLODataset を初期化し、セグメントとキーポイントを任意に設定します。

ソースコード ultralytics/data/dataset.py
def __init__(self, *args, data=None, task="detect", **kwargs):
    """Initializes the YOLODataset with optional configurations for segments and keypoints."""
    self.use_segments = task == "segment"
    self.use_keypoints = task == "pose"
    self.use_obb = task == "obb"
    self.data = data
    assert not (self.use_segments and self.use_keypoints), "Can not use both segments and keypoints."
    super().__init__(*args, **kwargs)

build_transforms(hyp=None)

トランスフォームを構築し、リストに追加する。

ソースコード ultralytics/data/dataset.py
def build_transforms(self, hyp=None):
    """Builds and appends transforms to the list."""
    if self.augment:
        hyp.mosaic = hyp.mosaic if self.augment and not self.rect else 0.0
        hyp.mixup = hyp.mixup if self.augment and not self.rect else 0.0
        transforms = v8_transforms(self, self.imgsz, hyp)
    else:
        transforms = Compose([LetterBox(new_shape=(self.imgsz, self.imgsz), scaleup=False)])
    transforms.append(
        Format(
            bbox_format="xywh",
            normalize=True,
            return_mask=self.use_segments,
            return_keypoint=self.use_keypoints,
            return_obb=self.use_obb,
            batch_idx=True,
            mask_ratio=hyp.mask_ratio,
            mask_overlap=hyp.overlap_mask,
            bgr=hyp.bgr if self.augment else 0.0,  # only affect training.
        )
    )
    return transforms

cache_labels(path=Path('./labels.cache'))

データセットのラベルをキャッシュし、画像をチェックし、形状を読み取る。

パラメーター

名称 タイプ 説明 デフォルト
path Path

キャッシュ・ファイルを保存するパス。デフォルトはPath('./labels.cache')です。

Path('./labels.cache')

リターンズ

タイプ 説明
dict

ラベル

ソースコード ultralytics/data/dataset.py
def cache_labels(self, path=Path("./labels.cache")):
    """
    Cache dataset labels, check images and read shapes.

    Args:
        path (Path): Path where to save the cache file. Default is Path('./labels.cache').

    Returns:
        (dict): labels.
    """
    x = {"labels": []}
    nm, nf, ne, nc, msgs = 0, 0, 0, 0, []  # number missing, found, empty, corrupt, messages
    desc = f"{self.prefix}Scanning {path.parent / path.stem}..."
    total = len(self.im_files)
    nkpt, ndim = self.data.get("kpt_shape", (0, 0))
    if self.use_keypoints and (nkpt <= 0 or ndim not in {2, 3}):
        raise ValueError(
            "'kpt_shape' in data.yaml missing or incorrect. Should be a list with [number of "
            "keypoints, number of dims (2 for x,y or 3 for x,y,visible)], i.e. 'kpt_shape: [17, 3]'"
        )
    with ThreadPool(NUM_THREADS) as pool:
        results = pool.imap(
            func=verify_image_label,
            iterable=zip(
                self.im_files,
                self.label_files,
                repeat(self.prefix),
                repeat(self.use_keypoints),
                repeat(len(self.data["names"])),
                repeat(nkpt),
                repeat(ndim),
            ),
        )
        pbar = TQDM(results, desc=desc, total=total)
        for im_file, lb, shape, segments, keypoint, nm_f, nf_f, ne_f, nc_f, msg in pbar:
            nm += nm_f
            nf += nf_f
            ne += ne_f
            nc += nc_f
            if im_file:
                x["labels"].append(
                    {
                        "im_file": im_file,
                        "shape": shape,
                        "cls": lb[:, 0:1],  # n, 1
                        "bboxes": lb[:, 1:],  # n, 4
                        "segments": segments,
                        "keypoints": keypoint,
                        "normalized": True,
                        "bbox_format": "xywh",
                    }
                )
            if msg:
                msgs.append(msg)
            pbar.desc = f"{desc} {nf} images, {nm + ne} backgrounds, {nc} corrupt"
        pbar.close()

    if msgs:
        LOGGER.info("\n".join(msgs))
    if nf == 0:
        LOGGER.warning(f"{self.prefix}WARNING ⚠️ No labels found in {path}. {HELP_URL}")
    x["hash"] = get_hash(self.label_files + self.im_files)
    x["results"] = nf, nm, ne, nc, len(self.im_files)
    x["msgs"] = msgs  # warnings
    save_dataset_cache_file(self.prefix, path, x, DATASET_CACHE_VERSION)
    return x

close_mosaic(hyp)

モザイク、copy_paste、mixup のオプションを 0.0 に設定し、トランスフォームを構築する。

ソースコード ultralytics/data/dataset.py
def close_mosaic(self, hyp):
    """Sets mosaic, copy_paste and mixup options to 0.0 and builds transformations."""
    hyp.mosaic = 0.0  # set mosaic ratio=0.0
    hyp.copy_paste = 0.0  # keep the same behavior as previous v8 close-mosaic
    hyp.mixup = 0.0  # keep the same behavior as previous v8 close-mosaic
    self.transforms = self.build_transforms(hyp)

collate_fn(batch) staticmethod

データサンプルをバッチにまとめる。

ソースコード ultralytics/data/dataset.py
@staticmethod
def collate_fn(batch):
    """Collates data samples into batches."""
    new_batch = {}
    keys = batch[0].keys()
    values = list(zip(*[list(b.values()) for b in batch]))
    for i, k in enumerate(keys):
        value = values[i]
        if k == "img":
            value = torch.stack(value, 0)
        if k in {"masks", "keypoints", "bboxes", "cls", "segments", "obb"}:
            value = torch.cat(value, 0)
        new_batch[k] = value
    new_batch["batch_idx"] = list(new_batch["batch_idx"])
    for i in range(len(new_batch["batch_idx"])):
        new_batch["batch_idx"][i] += i  # add target image index for build_targets()
    new_batch["batch_idx"] = torch.cat(new_batch["batch_idx"], 0)
    return new_batch

get_labels()

YOLO トレーニング用のラベルの辞書を返す。

ソースコード ultralytics/data/dataset.py
def get_labels(self):
    """Returns dictionary of labels for YOLO training."""
    self.label_files = img2label_paths(self.im_files)
    cache_path = Path(self.label_files[0]).parent.with_suffix(".cache")
    try:
        cache, exists = load_dataset_cache_file(cache_path), True  # attempt to load a *.cache file
        assert cache["version"] == DATASET_CACHE_VERSION  # matches current version
        assert cache["hash"] == get_hash(self.label_files + self.im_files)  # identical hash
    except (FileNotFoundError, AssertionError, AttributeError):
        cache, exists = self.cache_labels(cache_path), False  # run cache ops

    # Display cache
    nf, nm, ne, nc, n = cache.pop("results")  # found, missing, empty, corrupt, total
    if exists and LOCAL_RANK in {-1, 0}:
        d = f"Scanning {cache_path}... {nf} images, {nm + ne} backgrounds, {nc} corrupt"
        TQDM(None, desc=self.prefix + d, total=n, initial=n)  # display results
        if cache["msgs"]:
            LOGGER.info("\n".join(cache["msgs"]))  # display warnings

    # Read cache
    [cache.pop(k) for k in ("hash", "version", "msgs")]  # remove items
    labels = cache["labels"]
    if not labels:
        LOGGER.warning(f"WARNING ⚠️ No images found in {cache_path}, training may not work correctly. {HELP_URL}")
    self.im_files = [lb["im_file"] for lb in labels]  # update im_files

    # Check if the dataset is all boxes or all segments
    lengths = ((len(lb["cls"]), len(lb["bboxes"]), len(lb["segments"])) for lb in labels)
    len_cls, len_boxes, len_segments = (sum(x) for x in zip(*lengths))
    if len_segments and len_boxes != len_segments:
        LOGGER.warning(
            f"WARNING ⚠️ Box and segment counts should be equal, but got len(segments) = {len_segments}, "
            f"len(boxes) = {len_boxes}. To resolve this only boxes will be used and all segments will be removed. "
            "To avoid this please supply either a detect or segment dataset, not a detect-segment mixed dataset."
        )
        for lb in labels:
            lb["segments"] = []
    if len_cls == 0:
        LOGGER.warning(f"WARNING ⚠️ No labels found in {cache_path}, training may not work correctly. {HELP_URL}")
    return labels

update_labels_info(label)

ラベルフォーマットのカスタマイズはこちらから。

注

分類とセマンティックセグメンテーションには、独立したclsラベルが必要です。 dictキーを追加または削除することで、分類とセマンティックセグメンテーションをサポートすることもできる。

ソースコード ultralytics/data/dataset.py
def update_labels_info(self, label):
    """
    Custom your label format here.

    Note:
        cls is not with bboxes now, classification and semantic segmentation need an independent cls label
        Can also support classification and semantic segmentation by adding or removing dict keys there.
    """
    bboxes = label.pop("bboxes")
    segments = label.pop("segments", [])
    keypoints = label.pop("keypoints", None)
    bbox_format = label.pop("bbox_format")
    normalized = label.pop("normalized")

    # NOTE: do NOT resample oriented boxes
    segment_resamples = 100 if self.use_obb else 1000
    if len(segments) > 0:
        # list[np.array(1000, 2)] * num_samples
        # (N, 1000, 2)
        segments = np.stack(resample_segments(segments, n=segment_resamples), axis=0)
    else:
        segments = np.zeros((0, segment_resamples, 2), dtype=np.float32)
    label["instances"] = Instances(bboxes, segments, keypoints, bbox_format=bbox_format, normalized=normalized)
    return label



ultralytics.data.dataset.YOLOMultiModalDataset

ベース: YOLODataset

YOLO 形式のオブジェクト検出および/またはセグメンテーションラベルをロードするためのデータセットクラス。

パラメーター

名称 タイプ 説明 デフォルト
data dict

データセットYAML辞書。デフォルトは None です。

None
task str

現在のタスクを指定する明示的な引数。

'detect'

リターンズ

タイプ 説明
Dataset

PyTorch オブジェクト検出モデルの学習に使用できるデータセットオブジェクト。

ソースコード ultralytics/data/dataset.py
class YOLOMultiModalDataset(YOLODataset):
    """
    Dataset class for loading object detection and/or segmentation labels in YOLO format.

    Args:
        data (dict, optional): A dataset YAML dictionary. Defaults to None.
        task (str): An explicit arg to point current task, Defaults to 'detect'.

    Returns:
        (torch.utils.data.Dataset): A PyTorch dataset object that can be used for training an object detection model.
    """

    def __init__(self, *args, data=None, task="detect", **kwargs):
        """Initializes a dataset object for object detection tasks with optional specifications."""
        super().__init__(*args, data=data, task=task, **kwargs)

    def update_labels_info(self, label):
        """Add texts information for multi modal model training."""
        labels = super().update_labels_info(label)
        # NOTE: some categories are concatenated with its synonyms by `/`.
        labels["texts"] = [v.split("/") for _, v in self.data["names"].items()]
        return labels

    def build_transforms(self, hyp=None):
        """Enhances data transformations with optional text augmentation for multi-modal training."""
        transforms = super().build_transforms(hyp)
        if self.augment:
            # NOTE: hard-coded the args for now.
            transforms.insert(-1, RandomLoadText(max_samples=min(self.data["nc"], 80), padding=True))
        return transforms

__init__(*args, data=None, task='detect', **kwargs)

オブジェクト検出タスク用のデータセットオブジェクトをオプション指定で初期化する。

ソースコード ultralytics/data/dataset.py
def __init__(self, *args, data=None, task="detect", **kwargs):
    """Initializes a dataset object for object detection tasks with optional specifications."""
    super().__init__(*args, data=data, task=task, **kwargs)

build_transforms(hyp=None)

マルチモーダルトレーニングのためのオプションのテキスト補強でデータ変換を強化。

ソースコード ultralytics/data/dataset.py
def build_transforms(self, hyp=None):
    """Enhances data transformations with optional text augmentation for multi-modal training."""
    transforms = super().build_transforms(hyp)
    if self.augment:
        # NOTE: hard-coded the args for now.
        transforms.insert(-1, RandomLoadText(max_samples=min(self.data["nc"], 80), padding=True))
    return transforms

update_labels_info(label)

マルチモーダルモデルトレーニングのためのテキスト情報を追加。

ソースコード ultralytics/data/dataset.py
def update_labels_info(self, label):
    """Add texts information for multi modal model training."""
    labels = super().update_labels_info(label)
    # NOTE: some categories are concatenated with its synonyms by `/`.
    labels["texts"] = [v.split("/") for _, v in self.data["names"].items()]
    return labels



ultralytics.data.dataset.GroundingDataset

ベース: YOLODataset

ソースコード ultralytics/data/dataset.py
class GroundingDataset(YOLODataset):
    def __init__(self, *args, task="detect", json_file, **kwargs):
        """Initializes a GroundingDataset for object detection, loading annotations from a specified JSON file."""
        assert task == "detect", "`GroundingDataset` only support `detect` task for now!"
        self.json_file = json_file
        super().__init__(*args, task=task, data={}, **kwargs)

    def get_img_files(self, img_path):
        """The image files would be read in `get_labels` function, return empty list here."""
        return []

    def get_labels(self):
        """Loads annotations from a JSON file, filters, and normalizes bounding boxes for each image."""
        labels = []
        LOGGER.info("Loading annotation file...")
        with open(self.json_file, "r") as f:
            annotations = json.load(f)
        images = {f'{x["id"]:d}': x for x in annotations["images"]}
        imgToAnns = defaultdict(list)
        for ann in annotations["annotations"]:
            imgToAnns[ann["image_id"]].append(ann)
        for img_id, anns in TQDM(imgToAnns.items(), desc=f"Reading annotations {self.json_file}"):
            img = images[f"{img_id:d}"]
            h, w, f = img["height"], img["width"], img["file_name"]
            im_file = Path(self.img_path) / f
            if not im_file.exists():
                continue
            self.im_files.append(str(im_file))
            bboxes = []
            cat2id = {}
            texts = []
            for ann in anns:
                if ann["iscrowd"]:
                    continue
                box = np.array(ann["bbox"], dtype=np.float32)
                box[:2] += box[2:] / 2
                box[[0, 2]] /= float(w)
                box[[1, 3]] /= float(h)
                if box[2] <= 0 or box[3] <= 0:
                    continue

                cat_name = " ".join([img["caption"][t[0] : t[1]] for t in ann["tokens_positive"]])
                if cat_name not in cat2id:
                    cat2id[cat_name] = len(cat2id)
                    texts.append([cat_name])
                cls = cat2id[cat_name]  # class
                box = [cls] + box.tolist()
                if box not in bboxes:
                    bboxes.append(box)
            lb = np.array(bboxes, dtype=np.float32) if len(bboxes) else np.zeros((0, 5), dtype=np.float32)
            labels.append(
                {
                    "im_file": im_file,
                    "shape": (h, w),
                    "cls": lb[:, 0:1],  # n, 1
                    "bboxes": lb[:, 1:],  # n, 4
                    "normalized": True,
                    "bbox_format": "xywh",
                    "texts": texts,
                }
            )
        return labels

    def build_transforms(self, hyp=None):
        """Configures augmentations for training with optional text loading; `hyp` adjusts augmentation intensity."""
        transforms = super().build_transforms(hyp)
        if self.augment:
            # NOTE: hard-coded the args for now.
            transforms.insert(-1, RandomLoadText(max_samples=80, padding=True))
        return transforms

__init__(*args, task='detect', json_file, **kwargs)

オブジェクト検出用のGroundingDatasetを初期化し、指定されたJSONファイルからアノテーションを読み込みます。

ソースコード ultralytics/data/dataset.py
def __init__(self, *args, task="detect", json_file, **kwargs):
    """Initializes a GroundingDataset for object detection, loading annotations from a specified JSON file."""
    assert task == "detect", "`GroundingDataset` only support `detect` task for now!"
    self.json_file = json_file
    super().__init__(*args, task=task, data={}, **kwargs)

build_transforms(hyp=None)

オプションのテキストロードでトレーニングのオーグメントを設定します; hyp 補強強度を調整する。

ソースコード ultralytics/data/dataset.py
def build_transforms(self, hyp=None):
    """Configures augmentations for training with optional text loading; `hyp` adjusts augmentation intensity."""
    transforms = super().build_transforms(hyp)
    if self.augment:
        # NOTE: hard-coded the args for now.
        transforms.insert(-1, RandomLoadText(max_samples=80, padding=True))
    return transforms

get_img_files(img_path)

画像ファイルは get_labels 関数は、ここで空のリストを返す。

ソースコード ultralytics/data/dataset.py
def get_img_files(self, img_path):
    """The image files would be read in `get_labels` function, return empty list here."""
    return []

get_labels()

JSONファイルからアノテーションを読み込み、フィルタリングし、各画像のバウンディングボックスを正規化します。

ソースコード ultralytics/data/dataset.py
def get_labels(self):
    """Loads annotations from a JSON file, filters, and normalizes bounding boxes for each image."""
    labels = []
    LOGGER.info("Loading annotation file...")
    with open(self.json_file, "r") as f:
        annotations = json.load(f)
    images = {f'{x["id"]:d}': x for x in annotations["images"]}
    imgToAnns = defaultdict(list)
    for ann in annotations["annotations"]:
        imgToAnns[ann["image_id"]].append(ann)
    for img_id, anns in TQDM(imgToAnns.items(), desc=f"Reading annotations {self.json_file}"):
        img = images[f"{img_id:d}"]
        h, w, f = img["height"], img["width"], img["file_name"]
        im_file = Path(self.img_path) / f
        if not im_file.exists():
            continue
        self.im_files.append(str(im_file))
        bboxes = []
        cat2id = {}
        texts = []
        for ann in anns:
            if ann["iscrowd"]:
                continue
            box = np.array(ann["bbox"], dtype=np.float32)
            box[:2] += box[2:] / 2
            box[[0, 2]] /= float(w)
            box[[1, 3]] /= float(h)
            if box[2] <= 0 or box[3] <= 0:
                continue

            cat_name = " ".join([img["caption"][t[0] : t[1]] for t in ann["tokens_positive"]])
            if cat_name not in cat2id:
                cat2id[cat_name] = len(cat2id)
                texts.append([cat_name])
            cls = cat2id[cat_name]  # class
            box = [cls] + box.tolist()
            if box not in bboxes:
                bboxes.append(box)
        lb = np.array(bboxes, dtype=np.float32) if len(bboxes) else np.zeros((0, 5), dtype=np.float32)
        labels.append(
            {
                "im_file": im_file,
                "shape": (h, w),
                "cls": lb[:, 0:1],  # n, 1
                "bboxes": lb[:, 1:],  # n, 4
                "normalized": True,
                "bbox_format": "xywh",
                "texts": texts,
            }
        )
    return labels



ultralytics.data.dataset.YOLOConcatDataset

ベース: ConcatDataset

複数のデータセットを連結したデータセット。

このクラスは、さまざまな既存のデータセットを組み立てるのに便利です。

ソースコード ultralytics/data/dataset.py
class YOLOConcatDataset(ConcatDataset):
    """
    Dataset as a concatenation of multiple datasets.

    This class is useful to assemble different existing datasets.
    """

    @staticmethod
    def collate_fn(batch):
        """Collates data samples into batches."""
        return YOLODataset.collate_fn(batch)

collate_fn(batch) staticmethod

データサンプルをバッチにまとめる。

ソースコード ultralytics/data/dataset.py
@staticmethod
def collate_fn(batch):
    """Collates data samples into batches."""
    return YOLODataset.collate_fn(batch)



ultralytics.data.dataset.SemanticDataset

ベース: BaseDataset

セマンティック・セグメンテーション・データセット。

このクラスは、セマンティックセグメンテーションタスクで使用するデータセットの処理を担当します。このクラスは クラスの機能を継承します。

注

このクラスは現在プレースホルダーであり、セマンティック・セグメンテーション・タスクをサポートするメソッドと属性を追加する必要がある。 セマンティックセグメンテーションタスクをサポートするためのメソッドと属性を設定する必要があります。

ソースコード ultralytics/data/dataset.py
class SemanticDataset(BaseDataset):
    """
    Semantic Segmentation Dataset.

    This class is responsible for handling datasets used for semantic segmentation tasks. It inherits functionalities
    from the BaseDataset class.

    Note:
        This class is currently a placeholder and needs to be populated with methods and attributes for supporting
        semantic segmentation tasks.
    """

    def __init__(self):
        """Initialize a SemanticDataset object."""
        super().__init__()

__init__()

SemanticDatasetオブジェクトを初期化します。

ソースコード ultralytics/data/dataset.py
def __init__(self):
    """Initialize a SemanticDataset object."""
    super().__init__()



ultralytics.data.dataset.ClassificationDataset

torchvision ImageFolder を拡張し、YOLO 分類タスクをサポートします。 拡張、キャッシュ、検証などの機能を提供します。ディープラーニングモデルをトレーニングするための大規模なデータセットを効率的に処理するように設計されています。 オプションの画像変換とキャッシングメカニズムにより、学習を高速化します。

このクラスは、torchvision と Albumentations ライブラリの両方を使った補強が可能で、トレーニング中の IO オーバーヘッドを削減するために、RAM やディスクに画像をキャッシュすることができます。 をサポートします。さらに、データの整合性と一貫性を保証するために を実装しています。

属性:

名称 タイプ 説明
cache_ram bool

RAMでのキャッシュが有効かどうかを示す。

cache_disk bool

ディスク上のキャッシュが有効かどうかを示す。

samples list

タプルのリストで、それぞれ画像へのパス、クラスインデックス、.npyキャッシュファイルへのパス(ディスクにキャッシュする場合)、およびオプションとしてロードされた画像配列(RAMにキャッシュする場合)を含みます。 ファイルへのパス(ディスクにキャッシュする場合)、およびオプションとしてロードされたイメージ配列(RAMにキャッシュする場合)を含むタプルのリストです。

torch_transforms callable

PyTorch 画像に適用する変換。

ソースコード ultralytics/data/dataset.py
class ClassificationDataset:
    """
    Extends torchvision ImageFolder to support YOLO classification tasks, offering functionalities like image
    augmentation, caching, and verification. It's designed to efficiently handle large datasets for training deep
    learning models, with optional image transformations and caching mechanisms to speed up training.

    This class allows for augmentations using both torchvision and Albumentations libraries, and supports caching images
    in RAM or on disk to reduce IO overhead during training. Additionally, it implements a robust verification process
    to ensure data integrity and consistency.

    Attributes:
        cache_ram (bool): Indicates if caching in RAM is enabled.
        cache_disk (bool): Indicates if caching on disk is enabled.
        samples (list): A list of tuples, each containing the path to an image, its class index, path to its .npy cache
                        file (if caching on disk), and optionally the loaded image array (if caching in RAM).
        torch_transforms (callable): PyTorch transforms to be applied to the images.
    """

    def __init__(self, root, args, augment=False, prefix=""):
        """
        Initialize YOLO object with root, image size, augmentations, and cache settings.

        Args:
            root (str): Path to the dataset directory where images are stored in a class-specific folder structure.
            args (Namespace): Configuration containing dataset-related settings such as image size, augmentation
                parameters, and cache settings. It includes attributes like `imgsz` (image size), `fraction` (fraction
                of data to use), `scale`, `fliplr`, `flipud`, `cache` (disk or RAM caching for faster training),
                `auto_augment`, `hsv_h`, `hsv_s`, `hsv_v`, and `crop_fraction`.
            augment (bool, optional): Whether to apply augmentations to the dataset. Default is False.
            prefix (str, optional): Prefix for logging and cache filenames, aiding in dataset identification and
                debugging. Default is an empty string.
        """
        import torchvision  # scope for faster 'import ultralytics'

        # Base class assigned as attribute rather than used as base class to allow for scoping slow torchvision import
        self.base = torchvision.datasets.ImageFolder(root=root)
        self.samples = self.base.samples
        self.root = self.base.root

        # Initialize attributes
        if augment and args.fraction < 1.0:  # reduce training fraction
            self.samples = self.samples[: round(len(self.samples) * args.fraction)]
        self.prefix = colorstr(f"{prefix}: ") if prefix else ""
        self.cache_ram = args.cache is True or str(args.cache).lower() == "ram"  # cache images into RAM
        self.cache_disk = str(args.cache).lower() == "disk"  # cache images on hard drive as uncompressed *.npy files
        self.samples = self.verify_images()  # filter out bad images
        self.samples = [list(x) + [Path(x[0]).with_suffix(".npy"), None] for x in self.samples]  # file, index, npy, im
        scale = (1.0 - args.scale, 1.0)  # (0.08, 1.0)
        self.torch_transforms = (
            classify_augmentations(
                size=args.imgsz,
                scale=scale,
                hflip=args.fliplr,
                vflip=args.flipud,
                erasing=args.erasing,
                auto_augment=args.auto_augment,
                hsv_h=args.hsv_h,
                hsv_s=args.hsv_s,
                hsv_v=args.hsv_v,
            )
            if augment
            else classify_transforms(size=args.imgsz, crop_fraction=args.crop_fraction)
        )

    def __getitem__(self, i):
        """Returns subset of data and targets corresponding to given indices."""
        f, j, fn, im = self.samples[i]  # filename, index, filename.with_suffix('.npy'), image
        if self.cache_ram:
            if im is None:  # Warning: two separate if statements required here, do not combine this with previous line
                im = self.samples[i][3] = cv2.imread(f)
        elif self.cache_disk:
            if not fn.exists():  # load npy
                np.save(fn.as_posix(), cv2.imread(f), allow_pickle=False)
            im = np.load(fn)
        else:  # read image
            im = cv2.imread(f)  # BGR
        # Convert NumPy array to PIL image
        im = Image.fromarray(cv2.cvtColor(im, cv2.COLOR_BGR2RGB))
        sample = self.torch_transforms(im)
        return {"img": sample, "cls": j}

    def __len__(self) -> int:
        """Return the total number of samples in the dataset."""
        return len(self.samples)

    def verify_images(self):
        """Verify all images in dataset."""
        desc = f"{self.prefix}Scanning {self.root}..."
        path = Path(self.root).with_suffix(".cache")  # *.cache file path

        with contextlib.suppress(FileNotFoundError, AssertionError, AttributeError):
            cache = load_dataset_cache_file(path)  # attempt to load a *.cache file
            assert cache["version"] == DATASET_CACHE_VERSION  # matches current version
            assert cache["hash"] == get_hash([x[0] for x in self.samples])  # identical hash
            nf, nc, n, samples = cache.pop("results")  # found, missing, empty, corrupt, total
            if LOCAL_RANK in {-1, 0}:
                d = f"{desc} {nf} images, {nc} corrupt"
                TQDM(None, desc=d, total=n, initial=n)
                if cache["msgs"]:
                    LOGGER.info("\n".join(cache["msgs"]))  # display warnings
            return samples

        # Run scan if *.cache retrieval failed
        nf, nc, msgs, samples, x = 0, 0, [], [], {}
        with ThreadPool(NUM_THREADS) as pool:
            results = pool.imap(func=verify_image, iterable=zip(self.samples, repeat(self.prefix)))
            pbar = TQDM(results, desc=desc, total=len(self.samples))
            for sample, nf_f, nc_f, msg in pbar:
                if nf_f:
                    samples.append(sample)
                if msg:
                    msgs.append(msg)
                nf += nf_f
                nc += nc_f
                pbar.desc = f"{desc} {nf} images, {nc} corrupt"
            pbar.close()
        if msgs:
            LOGGER.info("\n".join(msgs))
        x["hash"] = get_hash([x[0] for x in self.samples])
        x["results"] = nf, nc, len(samples), samples
        x["msgs"] = msgs  # warnings
        save_dataset_cache_file(self.prefix, path, x, DATASET_CACHE_VERSION)
        return samples

__getitem__(i)

指定されたインデックスに対応するデータとターゲットのサブセットを返します。

ソースコード ultralytics/data/dataset.py
def __getitem__(self, i):
    """Returns subset of data and targets corresponding to given indices."""
    f, j, fn, im = self.samples[i]  # filename, index, filename.with_suffix('.npy'), image
    if self.cache_ram:
        if im is None:  # Warning: two separate if statements required here, do not combine this with previous line
            im = self.samples[i][3] = cv2.imread(f)
    elif self.cache_disk:
        if not fn.exists():  # load npy
            np.save(fn.as_posix(), cv2.imread(f), allow_pickle=False)
        im = np.load(fn)
    else:  # read image
        im = cv2.imread(f)  # BGR
    # Convert NumPy array to PIL image
    im = Image.fromarray(cv2.cvtColor(im, cv2.COLOR_BGR2RGB))
    sample = self.torch_transforms(im)
    return {"img": sample, "cls": j}

__init__(root, args, augment=False, prefix='')

ルート、画像サイズ、オーグメンテーション、キャッシュ設定でYOLO オブジェクトを初期化する。

パラメーター

名称 タイプ 説明 デフォルト
root str

クラス固有のフォルダ構造で画像が保存されているデータセットディレクトリへのパス。

必須
args Namespace

画像サイズ、オーグメンテーション・パラメータ、キャッシュ設定など、データセット関連の設定を含むコンフィギュレーション。 パラメータ、キャッシュ設定などのデータセット関連の設定が含まれます。以下のような属性が含まれます imgsz (画像サイズ)、 fraction (使用するデータの 使用するデータの割合)、 scale, fliplr, flipud, cache (高速トレーニングのためのディスクまたはRAMキャッシング)、 auto_augment, hsv_h, hsv_s, hsv_vそして crop_fraction.

必須
augment bool

データセットにオーグメントを適用するかどうか。デフォルトはFalse。

False
prefix str

ロギングとキャッシュのファイル名のプレフィックス。 デバッグに役立ちます。デフォルトは空文字列。

''
ソースコード ultralytics/data/dataset.py
def __init__(self, root, args, augment=False, prefix=""):
    """
    Initialize YOLO object with root, image size, augmentations, and cache settings.

    Args:
        root (str): Path to the dataset directory where images are stored in a class-specific folder structure.
        args (Namespace): Configuration containing dataset-related settings such as image size, augmentation
            parameters, and cache settings. It includes attributes like `imgsz` (image size), `fraction` (fraction
            of data to use), `scale`, `fliplr`, `flipud`, `cache` (disk or RAM caching for faster training),
            `auto_augment`, `hsv_h`, `hsv_s`, `hsv_v`, and `crop_fraction`.
        augment (bool, optional): Whether to apply augmentations to the dataset. Default is False.
        prefix (str, optional): Prefix for logging and cache filenames, aiding in dataset identification and
            debugging. Default is an empty string.
    """
    import torchvision  # scope for faster 'import ultralytics'

    # Base class assigned as attribute rather than used as base class to allow for scoping slow torchvision import
    self.base = torchvision.datasets.ImageFolder(root=root)
    self.samples = self.base.samples
    self.root = self.base.root

    # Initialize attributes
    if augment and args.fraction < 1.0:  # reduce training fraction
        self.samples = self.samples[: round(len(self.samples) * args.fraction)]
    self.prefix = colorstr(f"{prefix}: ") if prefix else ""
    self.cache_ram = args.cache is True or str(args.cache).lower() == "ram"  # cache images into RAM
    self.cache_disk = str(args.cache).lower() == "disk"  # cache images on hard drive as uncompressed *.npy files
    self.samples = self.verify_images()  # filter out bad images
    self.samples = [list(x) + [Path(x[0]).with_suffix(".npy"), None] for x in self.samples]  # file, index, npy, im
    scale = (1.0 - args.scale, 1.0)  # (0.08, 1.0)
    self.torch_transforms = (
        classify_augmentations(
            size=args.imgsz,
            scale=scale,
            hflip=args.fliplr,
            vflip=args.flipud,
            erasing=args.erasing,
            auto_augment=args.auto_augment,
            hsv_h=args.hsv_h,
            hsv_s=args.hsv_s,
            hsv_v=args.hsv_v,
        )
        if augment
        else classify_transforms(size=args.imgsz, crop_fraction=args.crop_fraction)
    )

__len__()

データセットに含まれるサンプルの総数を返す.

ソースコード ultralytics/data/dataset.py
def __len__(self) -> int:
    """Return the total number of samples in the dataset."""
    return len(self.samples)

verify_images()

データセットのすべての画像を検証する。

ソースコード ultralytics/data/dataset.py
def verify_images(self):
    """Verify all images in dataset."""
    desc = f"{self.prefix}Scanning {self.root}..."
    path = Path(self.root).with_suffix(".cache")  # *.cache file path

    with contextlib.suppress(FileNotFoundError, AssertionError, AttributeError):
        cache = load_dataset_cache_file(path)  # attempt to load a *.cache file
        assert cache["version"] == DATASET_CACHE_VERSION  # matches current version
        assert cache["hash"] == get_hash([x[0] for x in self.samples])  # identical hash
        nf, nc, n, samples = cache.pop("results")  # found, missing, empty, corrupt, total
        if LOCAL_RANK in {-1, 0}:
            d = f"{desc} {nf} images, {nc} corrupt"
            TQDM(None, desc=d, total=n, initial=n)
            if cache["msgs"]:
                LOGGER.info("\n".join(cache["msgs"]))  # display warnings
        return samples

    # Run scan if *.cache retrieval failed
    nf, nc, msgs, samples, x = 0, 0, [], [], {}
    with ThreadPool(NUM_THREADS) as pool:
        results = pool.imap(func=verify_image, iterable=zip(self.samples, repeat(self.prefix)))
        pbar = TQDM(results, desc=desc, total=len(self.samples))
        for sample, nf_f, nc_f, msg in pbar:
            if nf_f:
                samples.append(sample)
            if msg:
                msgs.append(msg)
            nf += nf_f
            nc += nc_f
            pbar.desc = f"{desc} {nf} images, {nc} corrupt"
        pbar.close()
    if msgs:
        LOGGER.info("\n".join(msgs))
    x["hash"] = get_hash([x[0] for x in self.samples])
    x["results"] = nf, nc, len(samples), samples
    x["msgs"] = msgs  # warnings
    save_dataset_cache_file(self.prefix, path, x, DATASET_CACHE_VERSION)
    return samples





Created 2023-11-12, Updated 2024-06-02
Authors: glenn-jocher (6), Burhan-Q (1), Laughing-q (1)