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ultralytics.models.sam.predict.Predictor

Bases : BasePredictor

Classe de prédicteur pour le modèle Segment Anything (SAM), étendant BasePredictor.

La classe fournit une interface pour l'inférence de modèle adaptée aux tâches de segmentation d'images. Grâce à son architecture avancée et à ses capacités de segmentation, elle facilite la génération de masques flexibles et en temps réel. flexible et en temps réel. La classe est capable de travailler avec différents types d'invites tels que les boîtes de délimitation, les points et les masques à faible résolution, les points et les masques à faible résolution.

Attributs :

Nom Type Description
cfg dict

Dictionnaire de configuration spécifiant les paramètres liés au modèle et aux tâches.

overrides dict

Dictionnaire contenant des valeurs qui remplacent la configuration par défaut.

_callbacks dict

Dictionnaire de fonctions de rappel définies par l'utilisateur pour augmenter le comportement.

args namespace

Espace de noms pour contenir les arguments de la ligne de commande ou d'autres variables opérationnelles.

im Tensor

Image d'entrée prétraitée tensor.

features Tensor

Les caractéristiques des images extraites sont utilisées pour l'inférence.

prompts dict

Collection de divers types de prompteurs, tels que les boîtes de délimitation et les points.

segment_all bool

Indicateur permettant de contrôler si l'on doit segmenter tous les objets de l'image ou seulement ceux qui sont spécifiés.

Code source dans ultralytics/models/sam/predict.py
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class Predictor(BasePredictor):
    """
    Predictor class for the Segment Anything Model (SAM), extending BasePredictor.

    The class provides an interface for model inference tailored to image segmentation tasks.
    With advanced architecture and promptable segmentation capabilities, it facilitates flexible and real-time
    mask generation. The class is capable of working with various types of prompts such as bounding boxes,
    points, and low-resolution masks.

    Attributes:
        cfg (dict): Configuration dictionary specifying model and task-related parameters.
        overrides (dict): Dictionary containing values that override the default configuration.
        _callbacks (dict): Dictionary of user-defined callback functions to augment behavior.
        args (namespace): Namespace to hold command-line arguments or other operational variables.
        im (torch.Tensor): Preprocessed input image tensor.
        features (torch.Tensor): Extracted image features used for inference.
        prompts (dict): Collection of various prompt types, such as bounding boxes and points.
        segment_all (bool): Flag to control whether to segment all objects in the image or only specified ones.
    """

    def __init__(self, cfg=DEFAULT_CFG, overrides=None, _callbacks=None):
        """
        Initialize the Predictor with configuration, overrides, and callbacks.

        The method sets up the Predictor object and applies any configuration overrides or callbacks provided. It
        initializes task-specific settings for SAM, such as retina_masks being set to True for optimal results.

        Args:
            cfg (dict): Configuration dictionary.
            overrides (dict, optional): Dictionary of values to override default configuration.
            _callbacks (dict, optional): Dictionary of callback functions to customize behavior.
        """
        if overrides is None:
            overrides = {}
        overrides.update(dict(task="segment", mode="predict", imgsz=1024))
        super().__init__(cfg, overrides, _callbacks)
        self.args.retina_masks = True
        self.im = None
        self.features = None
        self.prompts = {}
        self.segment_all = False

    def preprocess(self, im):
        """
        Preprocess the input image for model inference.

        The method prepares the input image by applying transformations and normalization.
        It supports both torch.Tensor and list of np.ndarray as input formats.

        Args:
            im (torch.Tensor | List[np.ndarray]): BCHW tensor format or list of HWC numpy arrays.

        Returns:
            (torch.Tensor): The preprocessed image tensor.
        """
        if self.im is not None:
            return self.im
        not_tensor = not isinstance(im, torch.Tensor)
        if not_tensor:
            im = np.stack(self.pre_transform(im))
            im = im[..., ::-1].transpose((0, 3, 1, 2))
            im = np.ascontiguousarray(im)
            im = torch.from_numpy(im)

        im = im.to(self.device)
        im = im.half() if self.model.fp16 else im.float()
        if not_tensor:
            im = (im - self.mean) / self.std
        return im

    def pre_transform(self, im):
        """
        Perform initial transformations on the input image for preprocessing.

        The method applies transformations such as resizing to prepare the image for further preprocessing.
        Currently, batched inference is not supported; hence the list length should be 1.

        Args:
            im (List[np.ndarray]): List containing images in HWC numpy array format.

        Returns:
            (List[np.ndarray]): List of transformed images.
        """
        assert len(im) == 1, "SAM model does not currently support batched inference"
        letterbox = LetterBox(self.args.imgsz, auto=False, center=False)
        return [letterbox(image=x) for x in im]

    def inference(self, im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False, *args, **kwargs):
        """
        Perform image segmentation inference based on the given input cues, using the currently loaded image. This
        method leverages SAM's (Segment Anything Model) architecture consisting of image encoder, prompt encoder, and
        mask decoder for real-time and promptable segmentation tasks.

        Args:
            im (torch.Tensor): The preprocessed input image in tensor format, with shape (N, C, H, W).
            bboxes (np.ndarray | List, optional): Bounding boxes with shape (N, 4), in XYXY format.
            points (np.ndarray | List, optional): Points indicating object locations with shape (N, 2), in pixels.
            labels (np.ndarray | List, optional): Labels for point prompts, shape (N, ). 1 = foreground, 0 = background.
            masks (np.ndarray, optional): Low-resolution masks from previous predictions shape (N,H,W). For SAM H=W=256.
            multimask_output (bool, optional): Flag to return multiple masks. Helpful for ambiguous prompts.

        Returns:
            (tuple): Contains the following three elements.
                - np.ndarray: The output masks in shape CxHxW, where C is the number of generated masks.
                - np.ndarray: An array of length C containing quality scores predicted by the model for each mask.
                - np.ndarray: Low-resolution logits of shape CxHxW for subsequent inference, where H=W=256.
        """
        # Override prompts if any stored in self.prompts
        bboxes = self.prompts.pop("bboxes", bboxes)
        points = self.prompts.pop("points", points)
        masks = self.prompts.pop("masks", masks)

        if all(i is None for i in [bboxes, points, masks]):
            return self.generate(im, *args, **kwargs)

        return self.prompt_inference(im, bboxes, points, labels, masks, multimask_output)

    def prompt_inference(self, im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False):
        """
        Internal function for image segmentation inference based on cues like bounding boxes, points, and masks.
        Leverages SAM's specialized architecture for prompt-based, real-time segmentation.

        Args:
            im (torch.Tensor): The preprocessed input image in tensor format, with shape (N, C, H, W).
            bboxes (np.ndarray | List, optional): Bounding boxes with shape (N, 4), in XYXY format.
            points (np.ndarray | List, optional): Points indicating object locations with shape (N, 2), in pixels.
            labels (np.ndarray | List, optional): Labels for point prompts, shape (N, ). 1 = foreground, 0 = background.
            masks (np.ndarray, optional): Low-resolution masks from previous predictions shape (N,H,W). For SAM H=W=256.
            multimask_output (bool, optional): Flag to return multiple masks. Helpful for ambiguous prompts.

        Returns:
            (tuple): Contains the following three elements.
                - np.ndarray: The output masks in shape CxHxW, where C is the number of generated masks.
                - np.ndarray: An array of length C containing quality scores predicted by the model for each mask.
                - np.ndarray: Low-resolution logits of shape CxHxW for subsequent inference, where H=W=256.
        """
        features = self.model.image_encoder(im) if self.features is None else self.features

        src_shape, dst_shape = self.batch[1][0].shape[:2], im.shape[2:]
        r = 1.0 if self.segment_all else min(dst_shape[0] / src_shape[0], dst_shape[1] / src_shape[1])
        # Transform input prompts
        if points is not None:
            points = torch.as_tensor(points, dtype=torch.float32, device=self.device)
            points = points[None] if points.ndim == 1 else points
            # Assuming labels are all positive if users don't pass labels.
            if labels is None:
                labels = np.ones(points.shape[0])
            labels = torch.as_tensor(labels, dtype=torch.int32, device=self.device)
            points *= r
            # (N, 2) --> (N, 1, 2), (N, ) --> (N, 1)
            points, labels = points[:, None, :], labels[:, None]
        if bboxes is not None:
            bboxes = torch.as_tensor(bboxes, dtype=torch.float32, device=self.device)
            bboxes = bboxes[None] if bboxes.ndim == 1 else bboxes
            bboxes *= r
        if masks is not None:
            masks = torch.as_tensor(masks, dtype=torch.float32, device=self.device).unsqueeze(1)

        points = (points, labels) if points is not None else None
        # Embed prompts
        sparse_embeddings, dense_embeddings = self.model.prompt_encoder(points=points, boxes=bboxes, masks=masks)

        # Predict masks
        pred_masks, pred_scores = self.model.mask_decoder(
            image_embeddings=features,
            image_pe=self.model.prompt_encoder.get_dense_pe(),
            sparse_prompt_embeddings=sparse_embeddings,
            dense_prompt_embeddings=dense_embeddings,
            multimask_output=multimask_output,
        )

        # (N, d, H, W) --> (N*d, H, W), (N, d) --> (N*d, )
        # `d` could be 1 or 3 depends on `multimask_output`.
        return pred_masks.flatten(0, 1), pred_scores.flatten(0, 1)

    def generate(
        self,
        im,
        crop_n_layers=0,
        crop_overlap_ratio=512 / 1500,
        crop_downscale_factor=1,
        point_grids=None,
        points_stride=32,
        points_batch_size=64,
        conf_thres=0.88,
        stability_score_thresh=0.95,
        stability_score_offset=0.95,
        crop_nms_thresh=0.7,
    ):
        """
        Perform image segmentation using the Segment Anything Model (SAM).

        This function segments an entire image into constituent parts by leveraging SAM's advanced architecture
        and real-time performance capabilities. It can optionally work on image crops for finer segmentation.

        Args:
            im (torch.Tensor): Input tensor representing the preprocessed image with dimensions (N, C, H, W).
            crop_n_layers (int): Specifies the number of layers for additional mask predictions on image crops.
                                 Each layer produces 2**i_layer number of image crops.
            crop_overlap_ratio (float): Determines the overlap between crops. Scaled down in subsequent layers.
            crop_downscale_factor (int): Scaling factor for the number of sampled points-per-side in each layer.
            point_grids (list[np.ndarray], optional): Custom grids for point sampling normalized to [0,1].
                                                      Used in the nth crop layer.
            points_stride (int, optional): Number of points to sample along each side of the image.
                                           Exclusive with 'point_grids'.
            points_batch_size (int): Batch size for the number of points processed simultaneously.
            conf_thres (float): Confidence threshold [0,1] for filtering based on the model's mask quality prediction.
            stability_score_thresh (float): Stability threshold [0,1] for mask filtering based on mask stability.
            stability_score_offset (float): Offset value for calculating stability score.
            crop_nms_thresh (float): IoU cutoff for NMS to remove duplicate masks between crops.

        Returns:
            (tuple): A tuple containing segmented masks, confidence scores, and bounding boxes.
        """
        import torchvision  # scope for faster 'import ultralytics'

        self.segment_all = True
        ih, iw = im.shape[2:]
        crop_regions, layer_idxs = generate_crop_boxes((ih, iw), crop_n_layers, crop_overlap_ratio)
        if point_grids is None:
            point_grids = build_all_layer_point_grids(points_stride, crop_n_layers, crop_downscale_factor)
        pred_masks, pred_scores, pred_bboxes, region_areas = [], [], [], []
        for crop_region, layer_idx in zip(crop_regions, layer_idxs):
            x1, y1, x2, y2 = crop_region
            w, h = x2 - x1, y2 - y1
            area = torch.tensor(w * h, device=im.device)
            points_scale = np.array([[w, h]])  # w, h
            # Crop image and interpolate to input size
            crop_im = F.interpolate(im[..., y1:y2, x1:x2], (ih, iw), mode="bilinear", align_corners=False)
            # (num_points, 2)
            points_for_image = point_grids[layer_idx] * points_scale
            crop_masks, crop_scores, crop_bboxes = [], [], []
            for (points,) in batch_iterator(points_batch_size, points_for_image):
                pred_mask, pred_score = self.prompt_inference(crop_im, points=points, multimask_output=True)
                # Interpolate predicted masks to input size
                pred_mask = F.interpolate(pred_mask[None], (h, w), mode="bilinear", align_corners=False)[0]
                idx = pred_score > conf_thres
                pred_mask, pred_score = pred_mask[idx], pred_score[idx]

                stability_score = calculate_stability_score(
                    pred_mask, self.model.mask_threshold, stability_score_offset
                )
                idx = stability_score > stability_score_thresh
                pred_mask, pred_score = pred_mask[idx], pred_score[idx]
                # Bool type is much more memory-efficient.
                pred_mask = pred_mask > self.model.mask_threshold
                # (N, 4)
                pred_bbox = batched_mask_to_box(pred_mask).float()
                keep_mask = ~is_box_near_crop_edge(pred_bbox, crop_region, [0, 0, iw, ih])
                if not torch.all(keep_mask):
                    pred_bbox, pred_mask, pred_score = pred_bbox[keep_mask], pred_mask[keep_mask], pred_score[keep_mask]

                crop_masks.append(pred_mask)
                crop_bboxes.append(pred_bbox)
                crop_scores.append(pred_score)

            # Do nms within this crop
            crop_masks = torch.cat(crop_masks)
            crop_bboxes = torch.cat(crop_bboxes)
            crop_scores = torch.cat(crop_scores)
            keep = torchvision.ops.nms(crop_bboxes, crop_scores, self.args.iou)  # NMS
            crop_bboxes = uncrop_boxes_xyxy(crop_bboxes[keep], crop_region)
            crop_masks = uncrop_masks(crop_masks[keep], crop_region, ih, iw)
            crop_scores = crop_scores[keep]

            pred_masks.append(crop_masks)
            pred_bboxes.append(crop_bboxes)
            pred_scores.append(crop_scores)
            region_areas.append(area.expand(len(crop_masks)))

        pred_masks = torch.cat(pred_masks)
        pred_bboxes = torch.cat(pred_bboxes)
        pred_scores = torch.cat(pred_scores)
        region_areas = torch.cat(region_areas)

        # Remove duplicate masks between crops
        if len(crop_regions) > 1:
            scores = 1 / region_areas
            keep = torchvision.ops.nms(pred_bboxes, scores, crop_nms_thresh)
            pred_masks, pred_bboxes, pred_scores = pred_masks[keep], pred_bboxes[keep], pred_scores[keep]

        return pred_masks, pred_scores, pred_bboxes

    def setup_model(self, model, verbose=True):
        """
        Initializes the Segment Anything Model (SAM) for inference.

        This method sets up the SAM model by allocating it to the appropriate device and initializing the necessary
        parameters for image normalization and other Ultralytics compatibility settings.

        Args:
            model (torch.nn.Module): A pre-trained SAM model. If None, a model will be built based on configuration.
            verbose (bool): If True, prints selected device information.

        Attributes:
            model (torch.nn.Module): The SAM model allocated to the chosen device for inference.
            device (torch.device): The device to which the model and tensors are allocated.
            mean (torch.Tensor): The mean values for image normalization.
            std (torch.Tensor): The standard deviation values for image normalization.
        """
        device = select_device(self.args.device, verbose=verbose)
        if model is None:
            model = build_sam(self.args.model)
        model.eval()
        self.model = model.to(device)
        self.device = device
        self.mean = torch.tensor([123.675, 116.28, 103.53]).view(-1, 1, 1).to(device)
        self.std = torch.tensor([58.395, 57.12, 57.375]).view(-1, 1, 1).to(device)

        # Ultralytics compatibility settings
        self.model.pt = False
        self.model.triton = False
        self.model.stride = 32
        self.model.fp16 = False
        self.done_warmup = True

    def postprocess(self, preds, img, orig_imgs):
        """
        Post-processes SAM's inference outputs to generate object detection masks and bounding boxes.

        The method scales masks and boxes to the original image size and applies a threshold to the mask predictions.
        The SAM model uses advanced architecture and promptable segmentation tasks to achieve real-time performance.

        Args:
            preds (tuple): The output from SAM model inference, containing masks, scores, and optional bounding boxes.
            img (torch.Tensor): The processed input image tensor.
            orig_imgs (list | torch.Tensor): The original, unprocessed images.

        Returns:
            (list): List of Results objects containing detection masks, bounding boxes, and other metadata.
        """
        # (N, 1, H, W), (N, 1)
        pred_masks, pred_scores = preds[:2]
        pred_bboxes = preds[2] if self.segment_all else None
        names = dict(enumerate(str(i) for i in range(len(pred_masks))))

        if not isinstance(orig_imgs, list):  # input images are a torch.Tensor, not a list
            orig_imgs = ops.convert_torch2numpy_batch(orig_imgs)

        results = []
        for i, masks in enumerate([pred_masks]):
            orig_img = orig_imgs[i]
            if pred_bboxes is not None:
                pred_bboxes = ops.scale_boxes(img.shape[2:], pred_bboxes.float(), orig_img.shape, padding=False)
                cls = torch.arange(len(pred_masks), dtype=torch.int32, device=pred_masks.device)
                pred_bboxes = torch.cat([pred_bboxes, pred_scores[:, None], cls[:, None]], dim=-1)

            masks = ops.scale_masks(masks[None].float(), orig_img.shape[:2], padding=False)[0]
            masks = masks > self.model.mask_threshold  # to bool
            img_path = self.batch[0][i]
            results.append(Results(orig_img, path=img_path, names=names, masks=masks, boxes=pred_bboxes))
        # Reset segment-all mode.
        self.segment_all = False
        return results

    def setup_source(self, source):
        """
        Sets up the data source for inference.

        This method configures the data source from which images will be fetched for inference. The source could be a
        directory, a video file, or other types of image data sources.

        Args:
            source (str | Path): The path to the image data source for inference.
        """
        if source is not None:
            super().setup_source(source)

    def set_image(self, image):
        """
        Preprocesses and sets a single image for inference.

        This function sets up the model if not already initialized, configures the data source to the specified image,
        and preprocesses the image for feature extraction. Only one image can be set at a time.

        Args:
            image (str | np.ndarray): Image file path as a string, or a np.ndarray image read by cv2.

        Raises:
            AssertionError: If more than one image is set.
        """
        if self.model is None:
            model = build_sam(self.args.model)
            self.setup_model(model)
        self.setup_source(image)
        assert len(self.dataset) == 1, "`set_image` only supports setting one image!"
        for batch in self.dataset:
            im = self.preprocess(batch[1])
            self.features = self.model.image_encoder(im)
            self.im = im
            break

    def set_prompts(self, prompts):
        """Set prompts in advance."""
        self.prompts = prompts

    def reset_image(self):
        """Resets the image and its features to None."""
        self.im = None
        self.features = None

    @staticmethod
    def remove_small_regions(masks, min_area=0, nms_thresh=0.7):
        """
        Perform post-processing on segmentation masks generated by the Segment Anything Model (SAM). Specifically, this
        function removes small disconnected regions and holes from the input masks, and then performs Non-Maximum
        Suppression (NMS) to eliminate any newly created duplicate boxes.

        Args:
            masks (torch.Tensor): A tensor containing the masks to be processed. Shape should be (N, H, W), where N is
                                  the number of masks, H is height, and W is width.
            min_area (int): The minimum area below which disconnected regions and holes will be removed. Defaults to 0.
            nms_thresh (float): The IoU threshold for the NMS algorithm. Defaults to 0.7.

        Returns:
            (tuple([torch.Tensor, List[int]])):
                - new_masks (torch.Tensor): The processed masks with small regions removed. Shape is (N, H, W).
                - keep (List[int]): The indices of the remaining masks post-NMS, which can be used to filter the boxes.
        """
        import torchvision  # scope for faster 'import ultralytics'

        if len(masks) == 0:
            return masks

        # Filter small disconnected regions and holes
        new_masks = []
        scores = []
        for mask in masks:
            mask = mask.cpu().numpy().astype(np.uint8)
            mask, changed = remove_small_regions(mask, min_area, mode="holes")
            unchanged = not changed
            mask, changed = remove_small_regions(mask, min_area, mode="islands")
            unchanged = unchanged and not changed

            new_masks.append(torch.as_tensor(mask).unsqueeze(0))
            # Give score=0 to changed masks and 1 to unchanged masks so NMS prefers masks not needing postprocessing
            scores.append(float(unchanged))

        # Recalculate boxes and remove any new duplicates
        new_masks = torch.cat(new_masks, dim=0)
        boxes = batched_mask_to_box(new_masks)
        keep = torchvision.ops.nms(boxes.float(), torch.as_tensor(scores), nms_thresh)

        return new_masks[keep].to(device=masks.device, dtype=masks.dtype), keep

__init__(cfg=DEFAULT_CFG, overrides=None, _callbacks=None)

Initialise le prédicteur avec la configuration, les dérogations et les rappels.

La méthode met en place l'objet Predictor et applique toutes les dérogations de configuration ou les rappels fournis. Elle initialise les paramètres spécifiques à la tâche pour SAM, par exemple les masques_rétina sont réglés sur True pour des résultats optimaux.

Paramètres :

Nom Type Description DĂ©faut
cfg dict

Dictionnaire de configuration.

DEFAULT_CFG
overrides dict

Dictionnaire de valeurs pour remplacer la configuration par défaut.

None
_callbacks dict

Dictionnaire des fonctions de rappel pour personnaliser le comportement.

None
Code source dans ultralytics/models/sam/predict.py
def __init__(self, cfg=DEFAULT_CFG, overrides=None, _callbacks=None):
    """
    Initialize the Predictor with configuration, overrides, and callbacks.

    The method sets up the Predictor object and applies any configuration overrides or callbacks provided. It
    initializes task-specific settings for SAM, such as retina_masks being set to True for optimal results.

    Args:
        cfg (dict): Configuration dictionary.
        overrides (dict, optional): Dictionary of values to override default configuration.
        _callbacks (dict, optional): Dictionary of callback functions to customize behavior.
    """
    if overrides is None:
        overrides = {}
    overrides.update(dict(task="segment", mode="predict", imgsz=1024))
    super().__init__(cfg, overrides, _callbacks)
    self.args.retina_masks = True
    self.im = None
    self.features = None
    self.prompts = {}
    self.segment_all = False

generate(im, crop_n_layers=0, crop_overlap_ratio=512 / 1500, crop_downscale_factor=1, point_grids=None, points_stride=32, points_batch_size=64, conf_thres=0.88, stability_score_thresh=0.95, stability_score_offset=0.95, crop_nms_thresh=0.7)

Effectue la segmentation de l'image à l'aide du modèle Segment Anything (SAM).

Cette fonction segmente une image entière en parties constitutives en tirant parti de l'architecture avancée et des capacités de performance en temps réel de SAM. et des capacités de performance en temps réel. Elle peut éventuellement travailler sur des coupes d'images pour une segmentation plus fine.

Paramètres :

Nom Type Description DĂ©faut
im Tensor

Entrée tensor représentant l'image prétraitée avec les dimensions (N, C, H, W).

requis
crop_n_layers int

Spécifie le nombre de couches pour les prédictions de masques supplémentaires sur les cultures d'images. Chaque couche produit 2**i_couche de cultures d'images.

0
crop_overlap_ratio float

DĂ©termine le chevauchement entre les cultures. Mise Ă  l'Ă©chelle dans les couches suivantes.

512 / 1500
crop_downscale_factor int

Facteur d'échelle pour le nombre de points échantillonnés par côté dans chaque couche.

1
point_grids list[ndarray]

Grilles personnalisées pour l'échantillonnage de points normalisés à [0,1]. Utilisées dans la nième couche de culture.

None
points_stride int

Nombre de points à échantillonner de chaque côté de l'image. Exclusif avec 'point_grids'.

32
points_batch_size int

Taille du lot pour le nombre de points traités simultanément.

64
conf_thres float

Seuil de confiance [0,1] pour le filtrage basé sur la prédiction de la qualité du masque du modèle.

0.88
stability_score_thresh float

Seuil de stabilité [0,1] pour le filtrage des masques basé sur la stabilité des masques.

0.95
stability_score_offset float

Valeur de décalage pour le calcul du score de stabilité.

0.95
crop_nms_thresh float

Le seuil de l'unité d'exploitation pour que le SGN supprime les masques en double entre les cultures.

0.7

Retourne :

Type Description
tuple

Un tuple contenant des masques segmentés, des scores de confiance et des boîtes de délimitation.

Code source dans ultralytics/models/sam/predict.py
def generate(
    self,
    im,
    crop_n_layers=0,
    crop_overlap_ratio=512 / 1500,
    crop_downscale_factor=1,
    point_grids=None,
    points_stride=32,
    points_batch_size=64,
    conf_thres=0.88,
    stability_score_thresh=0.95,
    stability_score_offset=0.95,
    crop_nms_thresh=0.7,
):
    """
    Perform image segmentation using the Segment Anything Model (SAM).

    This function segments an entire image into constituent parts by leveraging SAM's advanced architecture
    and real-time performance capabilities. It can optionally work on image crops for finer segmentation.

    Args:
        im (torch.Tensor): Input tensor representing the preprocessed image with dimensions (N, C, H, W).
        crop_n_layers (int): Specifies the number of layers for additional mask predictions on image crops.
                             Each layer produces 2**i_layer number of image crops.
        crop_overlap_ratio (float): Determines the overlap between crops. Scaled down in subsequent layers.
        crop_downscale_factor (int): Scaling factor for the number of sampled points-per-side in each layer.
        point_grids (list[np.ndarray], optional): Custom grids for point sampling normalized to [0,1].
                                                  Used in the nth crop layer.
        points_stride (int, optional): Number of points to sample along each side of the image.
                                       Exclusive with 'point_grids'.
        points_batch_size (int): Batch size for the number of points processed simultaneously.
        conf_thres (float): Confidence threshold [0,1] for filtering based on the model's mask quality prediction.
        stability_score_thresh (float): Stability threshold [0,1] for mask filtering based on mask stability.
        stability_score_offset (float): Offset value for calculating stability score.
        crop_nms_thresh (float): IoU cutoff for NMS to remove duplicate masks between crops.

    Returns:
        (tuple): A tuple containing segmented masks, confidence scores, and bounding boxes.
    """
    import torchvision  # scope for faster 'import ultralytics'

    self.segment_all = True
    ih, iw = im.shape[2:]
    crop_regions, layer_idxs = generate_crop_boxes((ih, iw), crop_n_layers, crop_overlap_ratio)
    if point_grids is None:
        point_grids = build_all_layer_point_grids(points_stride, crop_n_layers, crop_downscale_factor)
    pred_masks, pred_scores, pred_bboxes, region_areas = [], [], [], []
    for crop_region, layer_idx in zip(crop_regions, layer_idxs):
        x1, y1, x2, y2 = crop_region
        w, h = x2 - x1, y2 - y1
        area = torch.tensor(w * h, device=im.device)
        points_scale = np.array([[w, h]])  # w, h
        # Crop image and interpolate to input size
        crop_im = F.interpolate(im[..., y1:y2, x1:x2], (ih, iw), mode="bilinear", align_corners=False)
        # (num_points, 2)
        points_for_image = point_grids[layer_idx] * points_scale
        crop_masks, crop_scores, crop_bboxes = [], [], []
        for (points,) in batch_iterator(points_batch_size, points_for_image):
            pred_mask, pred_score = self.prompt_inference(crop_im, points=points, multimask_output=True)
            # Interpolate predicted masks to input size
            pred_mask = F.interpolate(pred_mask[None], (h, w), mode="bilinear", align_corners=False)[0]
            idx = pred_score > conf_thres
            pred_mask, pred_score = pred_mask[idx], pred_score[idx]

            stability_score = calculate_stability_score(
                pred_mask, self.model.mask_threshold, stability_score_offset
            )
            idx = stability_score > stability_score_thresh
            pred_mask, pred_score = pred_mask[idx], pred_score[idx]
            # Bool type is much more memory-efficient.
            pred_mask = pred_mask > self.model.mask_threshold
            # (N, 4)
            pred_bbox = batched_mask_to_box(pred_mask).float()
            keep_mask = ~is_box_near_crop_edge(pred_bbox, crop_region, [0, 0, iw, ih])
            if not torch.all(keep_mask):
                pred_bbox, pred_mask, pred_score = pred_bbox[keep_mask], pred_mask[keep_mask], pred_score[keep_mask]

            crop_masks.append(pred_mask)
            crop_bboxes.append(pred_bbox)
            crop_scores.append(pred_score)

        # Do nms within this crop
        crop_masks = torch.cat(crop_masks)
        crop_bboxes = torch.cat(crop_bboxes)
        crop_scores = torch.cat(crop_scores)
        keep = torchvision.ops.nms(crop_bboxes, crop_scores, self.args.iou)  # NMS
        crop_bboxes = uncrop_boxes_xyxy(crop_bboxes[keep], crop_region)
        crop_masks = uncrop_masks(crop_masks[keep], crop_region, ih, iw)
        crop_scores = crop_scores[keep]

        pred_masks.append(crop_masks)
        pred_bboxes.append(crop_bboxes)
        pred_scores.append(crop_scores)
        region_areas.append(area.expand(len(crop_masks)))

    pred_masks = torch.cat(pred_masks)
    pred_bboxes = torch.cat(pred_bboxes)
    pred_scores = torch.cat(pred_scores)
    region_areas = torch.cat(region_areas)

    # Remove duplicate masks between crops
    if len(crop_regions) > 1:
        scores = 1 / region_areas
        keep = torchvision.ops.nms(pred_bboxes, scores, crop_nms_thresh)
        pred_masks, pred_bboxes, pred_scores = pred_masks[keep], pred_bboxes[keep], pred_scores[keep]

    return pred_masks, pred_scores, pred_bboxes

inference(im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False, *args, **kwargs)

Effectue une inférence de segmentation d'image basée sur les indices d'entrée donnés, en utilisant l'image actuellement chargée. Cette Cette méthode s'appuie sur l'architecture de SAM(Segment Anything Model) composée d'un encodeur d'images, d'un encodeur d'invites et d'un décodeur de décodeur de masque pour les tâches de segmentation en temps réel et sur demande.

Paramètres :

Nom Type Description DĂ©faut
im Tensor

L'image d'entrée prétraitée au format tensor , avec la forme (N, C, H, W).

requis
bboxes ndarray | List

Boîtes de délimitation de forme (N, 4), au format XYXY.

None
points ndarray | List

Points indiquant l'emplacement des objets de forme (N, 2), en pixels.

None
labels ndarray | List

Étiquettes pour les invites de point, forme (N, ). 1 = premier plan, 0 = arrière-plan.

None
masks ndarray

Masques à faible résolution provenant de la forme des prédictions précédentes (N,H,W). Pour SAM H=W=256.

None
multimask_output bool

Drapeau pour renvoyer plusieurs masques. Utile pour les messages ambigus.

False

Retourne :

Type Description
tuple

Contient les trois éléments suivants. - np.ndarray : Les masques de sortie de forme CxHxW, où C est le nombre de masques générés. - np.ndarray : Un tableau de longueur C contenant les scores de qualité prédits par le modèle pour chaque masque. - np.ndarray : Logits à faible résolution de la forme CxHxW pour l'inférence ultérieure, où H=W=256.

Code source dans ultralytics/models/sam/predict.py
def inference(self, im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False, *args, **kwargs):
    """
    Perform image segmentation inference based on the given input cues, using the currently loaded image. This
    method leverages SAM's (Segment Anything Model) architecture consisting of image encoder, prompt encoder, and
    mask decoder for real-time and promptable segmentation tasks.

    Args:
        im (torch.Tensor): The preprocessed input image in tensor format, with shape (N, C, H, W).
        bboxes (np.ndarray | List, optional): Bounding boxes with shape (N, 4), in XYXY format.
        points (np.ndarray | List, optional): Points indicating object locations with shape (N, 2), in pixels.
        labels (np.ndarray | List, optional): Labels for point prompts, shape (N, ). 1 = foreground, 0 = background.
        masks (np.ndarray, optional): Low-resolution masks from previous predictions shape (N,H,W). For SAM H=W=256.
        multimask_output (bool, optional): Flag to return multiple masks. Helpful for ambiguous prompts.

    Returns:
        (tuple): Contains the following three elements.
            - np.ndarray: The output masks in shape CxHxW, where C is the number of generated masks.
            - np.ndarray: An array of length C containing quality scores predicted by the model for each mask.
            - np.ndarray: Low-resolution logits of shape CxHxW for subsequent inference, where H=W=256.
    """
    # Override prompts if any stored in self.prompts
    bboxes = self.prompts.pop("bboxes", bboxes)
    points = self.prompts.pop("points", points)
    masks = self.prompts.pop("masks", masks)

    if all(i is None for i in [bboxes, points, masks]):
        return self.generate(im, *args, **kwargs)

    return self.prompt_inference(im, bboxes, points, labels, masks, multimask_output)

postprocess(preds, img, orig_imgs)

Post-traite les résultats de l'inférence de SAM pour générer des masques de détection d'objets et des boîtes de délimitation.

La méthode adapte les masques et les boîtes à la taille de l'image originale et applique un seuil aux prédictions des masques. Le modèle SAM utilise une architecture avancée et des tâches de segmentation à déclencher pour obtenir des performances en temps réel.

Paramètres :

Nom Type Description DĂ©faut
preds tuple

Le résultat de l'inférence du modèle SAM , contenant les masques, les scores et les boîtes de délimitation optionnelles.

requis
img Tensor

L'image d'entrée traitée tensor.

requis
orig_imgs list | Tensor

Les images originales, non traitées.

requis

Retourne :

Type Description
list

Liste des objets Résultats contenant des masques de détection, des boîtes de délimitation et d'autres métadonnées.

Code source dans ultralytics/models/sam/predict.py
def postprocess(self, preds, img, orig_imgs):
    """
    Post-processes SAM's inference outputs to generate object detection masks and bounding boxes.

    The method scales masks and boxes to the original image size and applies a threshold to the mask predictions.
    The SAM model uses advanced architecture and promptable segmentation tasks to achieve real-time performance.

    Args:
        preds (tuple): The output from SAM model inference, containing masks, scores, and optional bounding boxes.
        img (torch.Tensor): The processed input image tensor.
        orig_imgs (list | torch.Tensor): The original, unprocessed images.

    Returns:
        (list): List of Results objects containing detection masks, bounding boxes, and other metadata.
    """
    # (N, 1, H, W), (N, 1)
    pred_masks, pred_scores = preds[:2]
    pred_bboxes = preds[2] if self.segment_all else None
    names = dict(enumerate(str(i) for i in range(len(pred_masks))))

    if not isinstance(orig_imgs, list):  # input images are a torch.Tensor, not a list
        orig_imgs = ops.convert_torch2numpy_batch(orig_imgs)

    results = []
    for i, masks in enumerate([pred_masks]):
        orig_img = orig_imgs[i]
        if pred_bboxes is not None:
            pred_bboxes = ops.scale_boxes(img.shape[2:], pred_bboxes.float(), orig_img.shape, padding=False)
            cls = torch.arange(len(pred_masks), dtype=torch.int32, device=pred_masks.device)
            pred_bboxes = torch.cat([pred_bboxes, pred_scores[:, None], cls[:, None]], dim=-1)

        masks = ops.scale_masks(masks[None].float(), orig_img.shape[:2], padding=False)[0]
        masks = masks > self.model.mask_threshold  # to bool
        img_path = self.batch[0][i]
        results.append(Results(orig_img, path=img_path, names=names, masks=masks, boxes=pred_bboxes))
    # Reset segment-all mode.
    self.segment_all = False
    return results

pre_transform(im)

Effectue les transformations initiales sur l'image d'entrée pour le prétraitement.

La méthode applique des transformations telles que le redimensionnement pour préparer l'image à un prétraitement ultérieur. Actuellement, l'inférence par lots n'est pas prise en charge, c'est pourquoi la longueur de la liste doit être de 1.

Paramètres :

Nom Type Description DĂ©faut
im List[ndarray]

Liste contenant des images au format HWC numpy array.

requis

Retourne :

Type Description
List[ndarray]

Liste des images transformées.

Code source dans ultralytics/models/sam/predict.py
def pre_transform(self, im):
    """
    Perform initial transformations on the input image for preprocessing.

    The method applies transformations such as resizing to prepare the image for further preprocessing.
    Currently, batched inference is not supported; hence the list length should be 1.

    Args:
        im (List[np.ndarray]): List containing images in HWC numpy array format.

    Returns:
        (List[np.ndarray]): List of transformed images.
    """
    assert len(im) == 1, "SAM model does not currently support batched inference"
    letterbox = LetterBox(self.args.imgsz, auto=False, center=False)
    return [letterbox(image=x) for x in im]

preprocess(im)

Prétraite l'image d'entrée pour l'inférence du modèle.

La méthode prépare l'image d'entrée en appliquant des transformations et une normalisation. Elle prend en charge les formats d'entrée torch.Tensor et list of np.ndarray.

Paramètres :

Nom Type Description DĂ©faut
im Tensor | List[ndarray]

Format BCHW tensor ou liste de tableaux numériques HWC.

requis

Retourne :

Type Description
Tensor

L'image prétraitée tensor.

Code source dans ultralytics/models/sam/predict.py
def preprocess(self, im):
    """
    Preprocess the input image for model inference.

    The method prepares the input image by applying transformations and normalization.
    It supports both torch.Tensor and list of np.ndarray as input formats.

    Args:
        im (torch.Tensor | List[np.ndarray]): BCHW tensor format or list of HWC numpy arrays.

    Returns:
        (torch.Tensor): The preprocessed image tensor.
    """
    if self.im is not None:
        return self.im
    not_tensor = not isinstance(im, torch.Tensor)
    if not_tensor:
        im = np.stack(self.pre_transform(im))
        im = im[..., ::-1].transpose((0, 3, 1, 2))
        im = np.ascontiguousarray(im)
        im = torch.from_numpy(im)

    im = im.to(self.device)
    im = im.half() if self.model.fp16 else im.float()
    if not_tensor:
        im = (im - self.mean) / self.std
    return im

prompt_inference(im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False)

Fonction interne d'inférence de segmentation d'image basée sur des indices tels que les boîtes de délimitation, les points et les masques. Exploite l'architecture spécialisée de SAM pour une segmentation en temps réel basée sur l'invite.

Paramètres :

Nom Type Description DĂ©faut
im Tensor

L'image d'entrée prétraitée au format tensor , avec la forme (N, C, H, W).

requis
bboxes ndarray | List

Boîtes de délimitation de forme (N, 4), au format XYXY.

None
points ndarray | List

Points indiquant l'emplacement des objets de forme (N, 2), en pixels.

None
labels ndarray | List

Étiquettes pour les invites de point, forme (N, ). 1 = premier plan, 0 = arrière-plan.

None
masks ndarray

Masques à faible résolution provenant de la forme des prédictions précédentes (N,H,W). Pour SAM H=W=256.

None
multimask_output bool

Drapeau pour renvoyer plusieurs masques. Utile pour les messages ambigus.

False

Retourne :

Type Description
tuple

Contient les trois éléments suivants. - np.ndarray : Les masques de sortie de forme CxHxW, où C est le nombre de masques générés. - np.ndarray : Un tableau de longueur C contenant les scores de qualité prédits par le modèle pour chaque masque. - np.ndarray : Logits à faible résolution de la forme CxHxW pour l'inférence ultérieure, où H=W=256.

Code source dans ultralytics/models/sam/predict.py
def prompt_inference(self, im, bboxes=None, points=None, labels=None, masks=None, multimask_output=False):
    """
    Internal function for image segmentation inference based on cues like bounding boxes, points, and masks.
    Leverages SAM's specialized architecture for prompt-based, real-time segmentation.

    Args:
        im (torch.Tensor): The preprocessed input image in tensor format, with shape (N, C, H, W).
        bboxes (np.ndarray | List, optional): Bounding boxes with shape (N, 4), in XYXY format.
        points (np.ndarray | List, optional): Points indicating object locations with shape (N, 2), in pixels.
        labels (np.ndarray | List, optional): Labels for point prompts, shape (N, ). 1 = foreground, 0 = background.
        masks (np.ndarray, optional): Low-resolution masks from previous predictions shape (N,H,W). For SAM H=W=256.
        multimask_output (bool, optional): Flag to return multiple masks. Helpful for ambiguous prompts.

    Returns:
        (tuple): Contains the following three elements.
            - np.ndarray: The output masks in shape CxHxW, where C is the number of generated masks.
            - np.ndarray: An array of length C containing quality scores predicted by the model for each mask.
            - np.ndarray: Low-resolution logits of shape CxHxW for subsequent inference, where H=W=256.
    """
    features = self.model.image_encoder(im) if self.features is None else self.features

    src_shape, dst_shape = self.batch[1][0].shape[:2], im.shape[2:]
    r = 1.0 if self.segment_all else min(dst_shape[0] / src_shape[0], dst_shape[1] / src_shape[1])
    # Transform input prompts
    if points is not None:
        points = torch.as_tensor(points, dtype=torch.float32, device=self.device)
        points = points[None] if points.ndim == 1 else points
        # Assuming labels are all positive if users don't pass labels.
        if labels is None:
            labels = np.ones(points.shape[0])
        labels = torch.as_tensor(labels, dtype=torch.int32, device=self.device)
        points *= r
        # (N, 2) --> (N, 1, 2), (N, ) --> (N, 1)
        points, labels = points[:, None, :], labels[:, None]
    if bboxes is not None:
        bboxes = torch.as_tensor(bboxes, dtype=torch.float32, device=self.device)
        bboxes = bboxes[None] if bboxes.ndim == 1 else bboxes
        bboxes *= r
    if masks is not None:
        masks = torch.as_tensor(masks, dtype=torch.float32, device=self.device).unsqueeze(1)

    points = (points, labels) if points is not None else None
    # Embed prompts
    sparse_embeddings, dense_embeddings = self.model.prompt_encoder(points=points, boxes=bboxes, masks=masks)

    # Predict masks
    pred_masks, pred_scores = self.model.mask_decoder(
        image_embeddings=features,
        image_pe=self.model.prompt_encoder.get_dense_pe(),
        sparse_prompt_embeddings=sparse_embeddings,
        dense_prompt_embeddings=dense_embeddings,
        multimask_output=multimask_output,
    )

    # (N, d, H, W) --> (N*d, H, W), (N, d) --> (N*d, )
    # `d` could be 1 or 3 depends on `multimask_output`.
    return pred_masks.flatten(0, 1), pred_scores.flatten(0, 1)

remove_small_regions(masks, min_area=0, nms_thresh=0.7) staticmethod

Effectuer un post-traitement sur les masques de segmentation générés par le modèle Segment Anything (SAM). Plus précisément, cette fonction supprime les petites régions déconnectées et les trous des masques d'entrée, puis effectue une suppression non maximale (NMS) pour éliminer les boîtes dupliquées nouvellement créées. Suppression non maximale (NMS) pour éliminer toutes les boîtes dupliquées nouvellement créées.

Paramètres :

Nom Type Description DĂ©faut
masks Tensor

Un tensor contenant les masques Ă  traiter. La forme doit ĂŞtre (N, H, W), oĂą N est le nombre de masques, H la hauteur et W la largeur. le nombre de masques, H la hauteur et W la largeur.

requis
min_area int

La zone minimale en dessous de laquelle les régions déconnectées et les trous seront supprimés. La valeur par défaut est 0.

0
nms_thresh float

Le seuil de l'interface utilisateur pour l'algorithme du SGN. La valeur par défaut est 0,7.

0.7

Retourne :

Type Description
tuple([Tensor, List[int]])
  • new_masks (torch.Tensor) : Les masques traitĂ©s avec les petites rĂ©gions supprimĂ©es. La forme est (N, H, W).
  • keep (List[int]) : Les indices des masques restants post-NMS, qui peuvent ĂŞtre utilisĂ©s pour filtrer les boĂ®tes.
Code source dans ultralytics/models/sam/predict.py
@staticmethod
def remove_small_regions(masks, min_area=0, nms_thresh=0.7):
    """
    Perform post-processing on segmentation masks generated by the Segment Anything Model (SAM). Specifically, this
    function removes small disconnected regions and holes from the input masks, and then performs Non-Maximum
    Suppression (NMS) to eliminate any newly created duplicate boxes.

    Args:
        masks (torch.Tensor): A tensor containing the masks to be processed. Shape should be (N, H, W), where N is
                              the number of masks, H is height, and W is width.
        min_area (int): The minimum area below which disconnected regions and holes will be removed. Defaults to 0.
        nms_thresh (float): The IoU threshold for the NMS algorithm. Defaults to 0.7.

    Returns:
        (tuple([torch.Tensor, List[int]])):
            - new_masks (torch.Tensor): The processed masks with small regions removed. Shape is (N, H, W).
            - keep (List[int]): The indices of the remaining masks post-NMS, which can be used to filter the boxes.
    """
    import torchvision  # scope for faster 'import ultralytics'

    if len(masks) == 0:
        return masks

    # Filter small disconnected regions and holes
    new_masks = []
    scores = []
    for mask in masks:
        mask = mask.cpu().numpy().astype(np.uint8)
        mask, changed = remove_small_regions(mask, min_area, mode="holes")
        unchanged = not changed
        mask, changed = remove_small_regions(mask, min_area, mode="islands")
        unchanged = unchanged and not changed

        new_masks.append(torch.as_tensor(mask).unsqueeze(0))
        # Give score=0 to changed masks and 1 to unchanged masks so NMS prefers masks not needing postprocessing
        scores.append(float(unchanged))

    # Recalculate boxes and remove any new duplicates
    new_masks = torch.cat(new_masks, dim=0)
    boxes = batched_mask_to_box(new_masks)
    keep = torchvision.ops.nms(boxes.float(), torch.as_tensor(scores), nms_thresh)

    return new_masks[keep].to(device=masks.device, dtype=masks.dtype), keep

reset_image()

Réinitialise l'image et ses caractéristiques à Aucun.

Code source dans ultralytics/models/sam/predict.py
def reset_image(self):
    """Resets the image and its features to None."""
    self.im = None
    self.features = None

set_image(image)

Prétraite et définit une seule image pour l'inférence.

Cette fonction configure le modèle s'il n'a pas déjà été initialisé, configure la source de données en fonction de l'image spécifiée, et prépare l'image pour l'extraction des caractéristiques. Une seule image peut être définie à la fois.

Paramètres :

Nom Type Description DĂ©faut
image str | ndarray

Chemin d'accès au fichier image sous forme de chaîne, ou image np.ndarray lue par cv2.

requis

Augmente :

Type Description
AssertionError

Si plus d'une image est définie.

Code source dans ultralytics/models/sam/predict.py
def set_image(self, image):
    """
    Preprocesses and sets a single image for inference.

    This function sets up the model if not already initialized, configures the data source to the specified image,
    and preprocesses the image for feature extraction. Only one image can be set at a time.

    Args:
        image (str | np.ndarray): Image file path as a string, or a np.ndarray image read by cv2.

    Raises:
        AssertionError: If more than one image is set.
    """
    if self.model is None:
        model = build_sam(self.args.model)
        self.setup_model(model)
    self.setup_source(image)
    assert len(self.dataset) == 1, "`set_image` only supports setting one image!"
    for batch in self.dataset:
        im = self.preprocess(batch[1])
        self.features = self.model.image_encoder(im)
        self.im = im
        break

set_prompts(prompts)

DĂ©finis les messages-guides Ă  l'avance.

Code source dans ultralytics/models/sam/predict.py
def set_prompts(self, prompts):
    """Set prompts in advance."""
    self.prompts = prompts

setup_model(model, verbose=True)

Initialise le modèle Segment Anything (SAM) pour l'inférence.

Cette méthode configure le modèle SAM en l'attribuant à l'appareil approprié et en initialisant les paramètres nécessaires à la normalisation de l'image et aux autres paramètres de compatibilité. pour la normalisation de l'image et d'autres paramètres de compatibilité Ultralytics .

Paramètres :

Nom Type Description DĂ©faut
model Module

Un modèle pré-entraîné SAM . Si Aucun, un modèle sera construit sur la base de la configuration.

requis
verbose bool

Si Vrai, imprime les informations sur l'appareil sélectionné.

True

Attributs :

Nom Type Description
model Module

Le modèle SAM attribué à l'appareil choisi pour l'inférence.

device device

L'appareil auquel le modèle et les tenseurs sont attribués.

mean Tensor

Les valeurs moyennes pour la normalisation de l'image.

std Tensor

Les valeurs d'Ă©cart-type pour la normalisation de l'image.

Code source dans ultralytics/models/sam/predict.py
def setup_model(self, model, verbose=True):
    """
    Initializes the Segment Anything Model (SAM) for inference.

    This method sets up the SAM model by allocating it to the appropriate device and initializing the necessary
    parameters for image normalization and other Ultralytics compatibility settings.

    Args:
        model (torch.nn.Module): A pre-trained SAM model. If None, a model will be built based on configuration.
        verbose (bool): If True, prints selected device information.

    Attributes:
        model (torch.nn.Module): The SAM model allocated to the chosen device for inference.
        device (torch.device): The device to which the model and tensors are allocated.
        mean (torch.Tensor): The mean values for image normalization.
        std (torch.Tensor): The standard deviation values for image normalization.
    """
    device = select_device(self.args.device, verbose=verbose)
    if model is None:
        model = build_sam(self.args.model)
    model.eval()
    self.model = model.to(device)
    self.device = device
    self.mean = torch.tensor([123.675, 116.28, 103.53]).view(-1, 1, 1).to(device)
    self.std = torch.tensor([58.395, 57.12, 57.375]).view(-1, 1, 1).to(device)

    # Ultralytics compatibility settings
    self.model.pt = False
    self.model.triton = False
    self.model.stride = 32
    self.model.fp16 = False
    self.done_warmup = True

setup_source(source)

Configure la source de données pour l'inférence.

Cette méthode configure la source de données à partir de laquelle les images seront récupérées pour l'inférence. La source peut être un un répertoire, un fichier vidéo ou d'autres types de sources de données d'images.

Paramètres :

Nom Type Description DĂ©faut
source str | Path

Le chemin d'accès à la source de données de l'image pour l'inférence.

requis
Code source dans ultralytics/models/sam/predict.py
def setup_source(self, source):
    """
    Sets up the data source for inference.

    This method configures the data source from which images will be fetched for inference. The source could be a
    directory, a video file, or other types of image data sources.

    Args:
        source (str | Path): The path to the image data source for inference.
    """
    if source is not None:
        super().setup_source(source)





Created 2023-11-12, Updated 2024-06-02
Authors: glenn-jocher (5), Burhan-Q (1)