📚 Docs changelog.md update

feature/update_to_support_sam

docs/annotation/voc.md

@@ -0,0 +1,3 @@
+## detections_to_voc_xml
+
+:::supervision.annotation.voc.detections_to_voc_xml

docs/changelog.md

@@ -0,0 +1,45 @@
+### 0.5.1 <small>April 12, 2023</small>
+
+- Fixed `Detections.__getitem__` method did not return mask for selected item.
+- Fixed `Detections.area` crashed for mask detections.
+
+### 0.5.0 <small>April 10, 2023</small>
+
+- Added [[#58](https://github.com/roboflow/supervision/pull/58)]: `Detections.mask` to enable segmentation support.
+- Added [[#58](https://github.com/roboflow/supervision/pull/58)]: `MaskAnnotator` to allow easy `Detections.mask` annotation.
+- Added [[#58](https://github.com/roboflow/supervision/pull/58)]: `Detections.from_sam` to enable native Segment Anything Model (SAM) support.
+- Changed [[#58](https://github.com/roboflow/supervision/pull/58)]: `Detections.area` behaviour to work not only with boxes but also with masks.
+
+### 0.4.0 <small>April 5, 2023</small> 
+
+- Added [[#46](https://github.com/roboflow/supervision/discussions/48)]: `Detections.empty` to allow easy creation of empty `Detections` objects.
+- Added [[#56](https://github.com/roboflow/supervision/pull/56)]: `Detections.from_roboflow` to allow easy creation of `Detections` objects from Roboflow API inference results.
+- Added [[#56](https://github.com/roboflow/supervision/pull/56)]: `plot_images_grid` to allow easy plotting of multiple images on single plot.
+- Added [[#56](https://github.com/roboflow/supervision/pull/56)]: initial support for Pascal VOC XML format with `detections_to_voc_xml` method.
+- Changed [[#56](https://github.com/roboflow/supervision/pull/56)]: `show_frame_in_notebook` refactored and renamed to `plot_image`.
+
+### 0.3.2 <small>March 23, 2023</small> 
+
+- Changed [[#50](https://github.com/roboflow/supervision/issues/50)]: Allow `Detections.class_id` to be `None`. 
+
+### 0.3.1 <small>March 6, 2023</small> 
+
+- Fixed [[#41](https://github.com/roboflow/supervision/issues/41)]: `PolygonZone` throws an exception when the object touches the bottom edge of the image.
+- Fixed [[#42](https://github.com/roboflow/supervision/issues/42)]: `Detections.wth_nms` method throws an exception when `Detections` is empty.
+- Changed [[#36](https://github.com/roboflow/supervision/pull/36)]: `Detections.wth_nms` support class agnostic and non-class agnostic case.
+
+### 0.3.0 <small>March 6, 2023</small> 
+
+- Changed: Allow `Detections.confidence` to be `None`.
+- Added: `Detections.from_transformers` and `Detections.from_detectron2` to enable seamless integration with Transformers and Detectron2 models. 
+- Added: `Detections.area` to dynamically calculate bounding box area.
+- Added: `Detections.wth_nms` to filter out double detections with NMS. Initial - only class agnostic - implementation. 
+
+### 0.2.0 <small>February 2, 2023</small> 
+
+- Added: Advanced `Detections` filtering with pandas-like API.
+- Added: `Detections.from_yolov5` and `Detections.from_yolov8` to enable seamless integration with YOLOv5 and YOLOv8 models.
+
+### 0.1.0 <small>January 19, 2023</small> 
+
+Say hello to Supervision 👋

docs/detection/annotate.md

@@ -1,3 +1,7 @@
 ## BoxAnnotator
 
-:::supervision.detection.annotate.BoxAnnotator
+:::supervision.detection.annotate.BoxAnnotator
+
+## MaskAnnotator
+
+:::supervision.detection.annotate.MaskAnnotator

docs/detection/tools/polygon_zone.md

@@ -0,0 +1,7 @@
+## PolygonZone
+
+:::supervision.detection.tools.polygon_zone.PolygonZone
+
+## PolygonZoneAnnotator
+
+:::supervision.detection.tools.polygon_zone.PolygonZoneAnnotator

docs/detection/utils.md

@@ -8,4 +8,8 @@
 
 ## non_max_suppression
 
-:::supervision.detection.utils.non_max_suppression
+:::supervision.detection.utils.non_max_suppression
+
+## mask_to_xyxy
+
+:::supervision.detection.utils.mask_to_xyxy

docs/notebook.md

@@ -1,3 +0,0 @@
-## show_frame_in_notebook
-
-:::supervision.notebook.utils.show_frame_in_notebook

docs/notebook/utils.md

@@ -0,0 +1,7 @@
+## plot_image
+
+:::supervision.notebook.utils.plot_image
+
+## plot_images_grid
+
+:::supervision.notebook.utils.plot_images_grid

mkdocs.yml

@@ -29,14 +29,20 @@ nav:
         - Core: detection/core.md
         - Annotate: detection/annotate.md
         - Utils: detection/utils.md
+        - Tools:
+            - Polygon Zone: detection/tools/polygon_zone.md
     - Draw:
-        - Utils: draw_utils.md
-    - Notebook: notebook.md
+        - Utils: draw/utils.md
+    - Annotations:
+        - Pascal VOC XML: annotation/voc.md
+    - Notebook:
+        - Utils: notebook/utils.md
+  - Changelog: changelog.md
 
 theme:
   name: 'material'
-  logo: https://media.roboflow.com/open-source/supervision/supervision-lenny.png?updatedAt=1678995918671
-  favicon: https://media.roboflow.com/open-source/supervision/supervision-lenny.png?updatedAt=1678995918671
+  logo: https://media.roboflow.com/open-source/supervision/supervision-lenny.png
+  favicon: https://media.roboflow.com/open-source/supervision/supervision-lenny.png
   palette:
     primary: 'deep purple'
     accent: 'teal'
@@ -51,4 +57,6 @@ plugins:
 markdown_extensions:
   - admonition
   - pymdownx.details
-  - pymdownx.superfences
+  - pymdownx.superfences
+  - toc:
+      permalink: true

supervision/__init__.py

@@ -1,15 +1,16 @@
-__version__ = "0.3.2"
+__version__ = "0.5.1"
 
-from supervision.detection.annotate import BoxAnnotator
+from supervision.annotation.voc import detections_to_voc_xml
+from supervision.detection.annotate import BoxAnnotator, MaskAnnotator
 from supervision.detection.core import Detections
 from supervision.detection.line_counter import LineZone, LineZoneAnnotator
-from supervision.detection.polygon_zone import PolygonZone, PolygonZoneAnnotator
-from supervision.detection.utils import generate_2d_mask
+from supervision.detection.tools.polygon_zone import PolygonZone, PolygonZoneAnnotator
+from supervision.detection.utils import generate_2d_mask, mask_to_xyxy
 from supervision.draw.color import Color, ColorPalette
 from supervision.draw.utils import draw_filled_rectangle, draw_polygon, draw_text
 from supervision.geometry.core import Point, Position, Rect
 from supervision.geometry.utils import get_polygon_center
-from supervision.notebook.utils import show_frame_in_notebook
+from supervision.notebook.utils import plot_image, plot_images_grid
 from supervision.video import (
     VideoInfo,
     VideoSink,

supervision/annotation/voc.py

@@ -0,0 +1,104 @@
+from typing import List
+from xml.dom.minidom import parseString
+from xml.etree.ElementTree import Element, SubElement, tostring
+
+from supervision.detection.core import Detections
+
+
+def detections_to_voc_xml(
+    detections: Detections,
+    classes: List[str],
+    filename: str,
+    width: int,
+    height: int,
+    depth: int = 3,
+) -> str:
+    """
+    Converts Detections object to Pascal VOC XML format.
+
+    Args:
+        detections (Detections): A Detections object containing bounding boxes, class ids, and other relevant information.
+        classes (List[str]): A list of class names corresponding to the class ids in the Detections object.
+        filename (str): The name of the image file associated with the detections.
+        width (int): The width of the image in pixels.
+        height (int): The height of the image in pixels.
+        depth (int, optional): The number of color channels in the image. Defaults to 3 for RGB images.
+
+    Returns:
+        str: An XML string in Pascal VOC format representing the detections.
+
+    Examples:
+        ```python
+        >>> import numpy as np
+        >>> import supervision as sv
+
+        >>> xyxy = np.array([
+        ...     [50, 30, 200, 180],
+        ...     [20, 40, 150, 190]
+        ... ])
+        >>> class_id = np.array([1, 0])
+        >>> detections = Detections(xyxy=xyxy, class_id=class_id)
+
+        >>> classes = ["dog", "cat"]
+
+        >>> voc_xml = detections_to_voc_xml(
+        ...     detections=detections,
+        ...     classes=classes,
+        ...     filename="image1.jpg",
+        ...     width=500,
+        ...     height=400
+        ... )
+        ```
+    """
+
+    # Create root element
+    annotation = Element("annotation")
+
+    # Add folder element
+    folder = SubElement(annotation, "folder")
+    folder.text = "VOC"
+
+    # Add filename element
+    fname = SubElement(annotation, "filename")
+    fname.text = filename
+
+    # Add source element
+    source = SubElement(annotation, "source")
+    database = SubElement(source, "database")
+    database.text = "roboflow.ai"
+
+    # Add size element
+    size = SubElement(annotation, "size")
+    w = SubElement(size, "width")
+    w.text = str(width)
+    h = SubElement(size, "height")
+    h.text = str(height)
+    d = SubElement(size, "depth")
+    d.text = str(depth)
+
+    # Add segmented element
+    segmented = SubElement(annotation, "segmented")
+    segmented.text = "0"
+
+    # Add object elements
+    for i in range(detections.xyxy.shape[0]):
+        obj = SubElement(annotation, "object")
+
+        class_id = detections.class_id[i] if detections.class_id is not None else None
+        name = SubElement(obj, "name")
+        name.text = classes[class_id] if class_id is not None else "unknown"
+
+        bndbox = SubElement(obj, "bndbox")
+        xmin = SubElement(bndbox, "xmin")
+        xmin.text = str(int(detections.xyxy[i, 0]))
+        ymin = SubElement(bndbox, "ymin")
+        ymin.text = str(int(detections.xyxy[i, 1]))
+        xmax = SubElement(bndbox, "xmax")
+        xmax.text = str(int(detections.xyxy[i, 2]))
+        ymax = SubElement(bndbox, "ymax")
+        ymax.text = str(int(detections.xyxy[i, 3]))
+
+    # Generate XML string
+    xml_string = parseString(tostring(annotation)).toprettyxml(indent="  ")
+
+    return xml_string

supervision/detection/annotate.py

@@ -56,8 +56,11 @@ class BoxAnnotator:
             np.ndarray: The image with the bounding boxes drawn on it
         """
         font = cv2.FONT_HERSHEY_SIMPLEX
-        for i, (xyxy, confidence, class_id, tracker_id) in enumerate(detections):
-            x1, y1, x2, y2 = xyxy.astype(int)
+        for i in range(len(detections)):
+            x1, y1, x2, y2 = detections.xyxy[i].astype(int)
+            class_id = (
+                detections.class_id[i] if detections.class_id is not None else None
+            )
             idx = class_id if class_id is not None else i
             color = (
                 self.color.by_idx(idx)
@@ -114,3 +117,58 @@ class BoxAnnotator:
                 lineType=cv2.LINE_AA,
             )
         return scene
+
+
+class MaskAnnotator:
+    """
+    A class for overlaying masks on an image using detections provided.
+
+    Attributes:
+        color (Union[Color, ColorPalette]): The color to fill the mask, can be a single color or a color palette
+    """
+
+    def __init__(
+        self,
+        color: Union[Color, ColorPalette] = ColorPalette.default(),
+    ):
+        self.color: Union[Color, ColorPalette] = color
+
+    def annotate(
+        self, scene: np.ndarray, detections: Detections, opacity: float = 0.5
+    ) -> np.ndarray:
+        """
+        Overlays the masks on the given image based on the provided detections, with a specified opacity.
+
+        Parameters:
+            scene (np.ndarray): The image on which the masks will be overlaid
+            detections (Detections): The detections for which the masks will be overlaid
+            opacity (float): The opacity of the masks, between 0 and 1, default is 0.5
+
+        Returns:
+            np.ndarray: The image with the masks overlaid
+        """
+        for i in range(len(detections.xyxy)):
+            if detections.mask is None:
+                continue
+
+            class_id = (
+                detections.class_id[i] if detections.class_id is not None else None
+            )
+            idx = class_id if class_id is not None else i
+            color = (
+                self.color.by_idx(idx)
+                if isinstance(self.color, ColorPalette)
+                else self.color
+            )
+
+            mask = detections.mask[i]
+            colored_mask = np.zeros_like(scene, dtype=np.uint8)
+            colored_mask[:] = color.as_bgr()
+
+            scene = np.where(
+                np.expand_dims(mask, axis=-1),
+                np.uint8(opacity * colored_mask + (1 - opacity) * scene),
+                scene,
+            )
+
+        return scene

supervision/detection/core.py

@@ -1,14 +1,52 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import Iterator, Optional, Tuple, Union
+from typing import Any, Iterator, List, Optional, Tuple, Union
 
 import numpy as np
 
-from supervision.detection.utils import non_max_suppression
+from supervision.detection.utils import non_max_suppression, xywh_to_xyxy
 from supervision.geometry.core import Position
 
 
+def _validate_xyxy(xyxy: Any, n: int) -> None:
+    is_valid = isinstance(xyxy, np.ndarray) and xyxy.shape == (n, 4)
+    if not is_valid:
+        raise ValueError("xyxy must be 2d np.ndarray with (n, 4) shape")
+
+
+def _validate_mask(mask: Any, n: int) -> None:
+    is_valid = mask is None or (
+        isinstance(mask, np.ndarray) and len(mask.shape) == 3 and mask.shape[0] == n
+    )
+    if not is_valid:
+        raise ValueError("mask must be 3d np.ndarray with (n, W, H) shape")
+
+
+def _validate_class_id(class_id: Any, n: int) -> None:
+    is_valid = class_id is None or (
+        isinstance(class_id, np.ndarray) and class_id.shape == (n,)
+    )
+    if not is_valid:
+        raise ValueError("class_id must be None or 1d np.ndarray with (n,) shape")
+
+
+def _validate_confidence(confidence: Any, n: int) -> None:
+    is_valid = confidence is None or (
+        isinstance(confidence, np.ndarray) and confidence.shape == (n,)
+    )
+    if not is_valid:
+        raise ValueError("confidence must be None or 1d np.ndarray with (n,) shape")
+
+
+def _validate_tracker_id(tracker_id: Any, n: int) -> None:
+    is_valid = tracker_id is None or (
+        isinstance(tracker_id, np.ndarray) and tracker_id.shape == (n,)
+    )
+    if not is_valid:
+        raise ValueError("tracker_id must be None or 1d np.ndarray with (n,) shape")
+
+
 @dataclass
 class Detections:
     """
@@ -16,40 +54,25 @@ class Detections:
 
     Attributes:
         xyxy (np.ndarray): An array of shape `(n, 4)` containing the bounding boxes coordinates in format `[x1, y1, x2, y2]`
+        mask: (Optional[np.ndarray]): An array of shape `(n, W, H)` containing the segmentation masks.
         class_id (Optional[np.ndarray]): An array of shape `(n,)` containing the class ids of the detections.
         confidence (Optional[np.ndarray]): An array of shape `(n,)` containing the confidence scores of the detections.
         tracker_id (Optional[np.ndarray]): An array of shape `(n,)` containing the tracker ids of the detections.
     """
 
     xyxy: np.ndarray
+    mask: np.Optional[np.ndarray] = None
     class_id: Optional[np.ndarray] = None
     confidence: Optional[np.ndarray] = None
     tracker_id: Optional[np.ndarray] = None
 
     def __post_init__(self):
         n = len(self.xyxy)
-        validators = [
-            (isinstance(self.xyxy, np.ndarray) and self.xyxy.shape == (n, 4)),
-            self.class_id is None
-            or (isinstance(self.class_id, np.ndarray) and self.class_id.shape == (n,)),
-            self.confidence is None
-            or (
-                isinstance(self.confidence, np.ndarray)
-                and self.confidence.shape == (n,)
-            ),
-            self.tracker_id is None
-            or (
-                isinstance(self.tracker_id, np.ndarray)
-                and self.tracker_id.shape == (n,)
-            ),
-        ]
-        if not all(validators):
-            raise ValueError(
-                "xyxy must be 2d np.ndarray with (n, 4) shape, "
-                "class_id must be None or 1d np.ndarray with (n,) shape, "
-                "confidence must be None or 1d np.ndarray with (n,) shape, "
-                "tracker_id must be None or 1d np.ndarray with (n,) shape"
-            )
+        _validate_xyxy(xyxy=self.xyxy, n=n)
+        _validate_mask(mask=self.mask, n=n)
+        _validate_class_id(class_id=self.class_id, n=n)
+        _validate_confidence(confidence=self.confidence, n=n)
+        _validate_tracker_id(tracker_id=self.tracker_id, n=n)
 
     def __len__(self):
         """
@@ -59,13 +82,22 @@ class Detections:
 
     def __iter__(
         self,
-    ) -> Iterator[Tuple[np.ndarray, Optional[float], int, Optional[Union[str, int]]]]:
+    ) -> Iterator[
+        Tuple[
+            np.ndarray,
+            Optional[np.ndarray],
+            Optional[float],
+            Optional[int],
+            Optional[int],
+        ]
+    ]:
         """
-        Iterates over the Detections object and yield a tuple of `(xyxy, confidence, class_id, tracker_id)` for each detection.
+        Iterates over the Detections object and yield a tuple of `(xyxy, mask, confidence, class_id, tracker_id)` for each detection.
         """
         for i in range(len(self.xyxy)):
             yield (
                 self.xyxy[i],
+                self.mask[i] if self.mask is not None else None,
                 self.confidence[i] if self.confidence is not None else None,
                 self.class_id[i] if self.class_id is not None else None,
                 self.tracker_id[i] if self.tracker_id is not None else None,
@@ -75,6 +107,12 @@ class Detections:
         return all(
             [
                 np.array_equal(self.xyxy, other.xyxy),
+                any(
+                    [
+                        self.mask is None and other.mask is None,
+                        np.array_equal(self.mask, other.mask),
+                    ]
+                ),
                 any(
                     [
                         self.class_id is None and other.class_id is None,
@@ -113,7 +151,7 @@ class Detections:
             >>> from supervision import Detections
 
             >>> model = torch.hub.load('ultralytics/yolov5', 'yolov5s')
-            >>> results = model(frame)
+            >>> results = model(IMAGE)
             >>> detections = Detections.from_yolov5(results)
             ```
         """
@@ -141,8 +179,8 @@ class Detections:
             >>> from supervision import Detections
 
             >>> model = YOLO('yolov8s.pt')
-            >>> results = model(frame)[0]
-            >>> detections = Detections.from_yolov8(results)
+            >>> yolov8_results = model(IMAGE)[0]
+            >>> detections = Detections.from_yolov8(yolov8_results)
             ```
         """
         return cls(
@@ -176,6 +214,62 @@ class Detections:
             .astype(int),
         )
 
+    @classmethod
+    def from_roboflow(cls, roboflow_result: dict, class_list: List[str]) -> Detections:
+        xyxy = []
+        confidence = []
+        class_id = []
+
+        for prediction in roboflow_result["predictions"]:
+            x = prediction["x"]
+            y = prediction["y"]
+            width = prediction["width"]
+            height = prediction["height"]
+            x_min = x - width / 2
+            y_min = y - height / 2
+            x_max = x_min + width
+            y_max = y_min + height
+            xyxy.append([x_min, y_min, x_max, y_max])
+            class_id.append(class_list.index(prediction["class"]))
+            confidence.append(prediction["confidence"])
+
+        return Detections(
+            xyxy=np.array(xyxy),
+            confidence=np.array(confidence),
+            class_id=np.array(class_id).astype(int),
+        )
+
+    @classmethod
+    def from_sam(cls, sam_result: List[dict]) -> Detections:
+        """
+        Creates a Detections instance from Segment Anything Model (SAM) by Meta AI.
+
+        Args:
+            sam_result (List[dict]): The output Results instance from SAM
+
+        Returns:
+            Detections: A new Detections object.
+
+        Example:
+            ```python
+            >>> from segment_anything import sam_model_registry, SamAutomaticMaskGenerator
+            >>> import supervision as sv
+
+            >>> sam = sam_model_registry[MODEL_TYPE](checkpoint=CHECKPOINT_PATH).to(device=DEVICE)
+            >>> mask_generator = SamAutomaticMaskGenerator(sam)
+            >>> sam_result = mask_generator.generate(IMAGE)
+            >>> detections = sv.Detections.from_sam(sam_result=sam_result)
+            ```
+        """
+        sorted_generated_masks = sorted(
+            sam_result, key=lambda x: x["area"], reverse=True
+        )
+
+        xywh = np.array([mask["bbox"] for mask in sorted_generated_masks])
+        mask = np.array([mask["segmentation"] for mask in sorted_generated_masks])
+
+        return Detections(xyxy=xywh_to_xyxy(boxes_xywh=xywh), mask=mask)
+
     @classmethod
     def from_coco_annotations(cls, coco_annotation: dict) -> Detections:
         xyxy, class_id = [], []
@@ -187,6 +281,14 @@ class Detections:
 
         return cls(xyxy=np.array(xyxy), class_id=np.array(class_id))
 
+    @classmethod
+    def empty(cls) -> Detections:
+        return cls(
+            xyxy=np.empty((0, 4), dtype=np.float32),
+            confidence=np.array([], dtype=np.float32),
+            class_id=np.array([], dtype=int),
+        )
+
     def get_anchor_coordinates(self, anchor: Position) -> np.ndarray:
         """
         Returns the bounding box coordinates for a specific anchor.
@@ -217,6 +319,9 @@ class Detections:
         ):
             return Detections(
                 xyxy=self.xyxy[index],
+                mask=self.mask[index]
+                if self.mask is not None
+                else None,
                 confidence=self.confidence[index]
                 if self.confidence is not None
                 else None,
@@ -231,6 +336,20 @@ class Detections:
 
     @property
     def area(self) -> np.ndarray:
+        """
+        Calculate the area of each detection in the set of object detections. If masks field is defined property
+        returns are of each mask. If only box is given property return area of each box.
+
+        Returns:
+          np.ndarray: An array of floats containing the area of each detection in the format of `(area_1, area_2, ..., area_n)`, where n is the number of detections.
+        """
+        if self.mask is not None:
+            return np.array([np.sum(mask) for mask in self.mask])
+        else:
+            return self.box_area
+
+    @property
+    def box_area(self) -> np.ndarray:
         """
         Calculate the area of each bounding box in the set of object detections.
 

supervision/detection/tools/polygon_zone.py

@@ -13,6 +13,17 @@ from supervision.geometry.utils import get_polygon_center
 
 
 class PolygonZone:
+    """
+    A class for defining a polygon-shaped zone within a frame for detecting objects.
+
+    Attributes:
+        polygon (np.ndarray): A numpy array defining the polygon vertices
+        frame_resolution_wh (Tuple[int, int]): The frame resolution (width, height)
+        triggering_position (Position): The position within the bounding box that triggers the zone (default: Position.BOTTOM_CENTER)
+        current_count (int): The current count of detected objects within the zone
+        mask (np.ndarray): The 2D bool mask for the polygon zone
+    """
+
     def __init__(
         self,
         polygon: np.ndarray,
@@ -30,6 +41,16 @@ class PolygonZone:
         )
 
     def trigger(self, detections: Detections) -> np.ndarray:
+        """
+        Determines if the detections are within the polygon zone.
+
+        Parameters:
+            detections (Detections): The detections to be checked against the polygon zone
+
+        Returns:
+            np.ndarray: A boolean numpy array indicating if each detection is within the polygon zone
+        """
+
         clipped_xyxy = clip_boxes(
             boxes_xyxy=detections.xyxy, frame_resolution_wh=self.frame_resolution_wh
         )
@@ -43,6 +64,21 @@ class PolygonZone:
 
 
 class PolygonZoneAnnotator:
+    """
+    A class for annotating a polygon-shaped zone within a frame with a count of detected objects.
+
+    Attributes:
+        zone (PolygonZone): The polygon zone to be annotated
+        color (Color): The color to draw the polygon lines
+        thickness (int): The thickness of the polygon lines, default is 2
+        text_color (Color): The color of the text on the polygon, default is black
+        text_scale (float): The scale of the text on the polygon, default is 0.5
+        text_thickness (int): The thickness of the text on the polygon, default is 1
+        text_padding (int): The padding around the text on the polygon, default is 10
+        font (int): The font type for the text on the polygon, default is cv2.FONT_HERSHEY_SIMPLEX
+        center (Tuple[int, int]): The center of the polygon for text placement
+    """
+
     def __init__(
         self,
         zone: PolygonZone,
@@ -64,6 +100,16 @@ class PolygonZoneAnnotator:
         self.center = get_polygon_center(polygon=zone.polygon)
 
     def annotate(self, scene: np.ndarray, label: Optional[str] = None) -> np.ndarray:
+        """
+        Annotates the polygon zone within a frame with a count of detected objects.
+
+        Parameters:
+            scene (np.ndarray): The image on which the polygon zone will be annotated
+            label (Optional[str]): An optional label for the count of detected objects within the polygon zone (default: None)
+
+        Returns:
+            np.ndarray: The image with the polygon zone and count of detected objects
+        """
         annotated_frame = draw_polygon(
             scene=scene,
             polygon=self.zone.polygon,

supervision/detection/utils.py

@@ -115,3 +115,34 @@ def clip_boxes(
     result[:, [0, 2]] = result[:, [0, 2]].clip(0, width)
     result[:, [1, 3]] = result[:, [1, 3]].clip(0, height)
     return result
+
+
+def xywh_to_xyxy(boxes_xywh: np.ndarray) -> np.ndarray:
+    xyxy = boxes_xywh.copy()
+    xyxy[:, 2] = boxes_xywh[:, 0] + boxes_xywh[:, 2]
+    xyxy[:, 3] = boxes_xywh[:, 1] + boxes_xywh[:, 3]
+    return xyxy
+
+
+def mask_to_xyxy(masks: np.ndarray) -> np.ndarray:
+    """
+    Converts a 3D `np.array` of 2D bool masks into a 2D `np.array` of bounding boxes.
+
+    Parameters:
+        masks (np.ndarray): A 3D `np.array` of shape `(N, W, H)` containing 2D bool masks
+
+    Returns:
+        np.ndarray: A 2D `np.array` of shape `(N, 4)` containing the bounding boxes `(x_min, y_min, x_max, y_max)` for each mask
+    """
+    n = masks.shape[0]
+    bboxes = np.zeros((n, 4), dtype=int)
+
+    for i, mask in enumerate(masks):
+        rows, cols = np.where(mask)
+
+        if len(rows) > 0 and len(cols) > 0:
+            x_min, x_max = np.min(cols), np.max(cols)
+            y_min, y_max = np.min(rows), np.max(rows)
+            bboxes[i, :] = [x_min, y_min, x_max, y_max]
+
+    return bboxes

supervision/notebook/utils.py

@@ -1,33 +1,97 @@
-from typing import Tuple
+from typing import List, Optional, Tuple
 
 import cv2
 import matplotlib.pyplot as plt
 import numpy as np
 
 
-def show_frame_in_notebook(
-    frame: np.ndarray, size: Tuple[int, int] = (10, 10), cmap: str = "gray"
-):
+def plot_image(
+    image: np.ndarray, size: Tuple[int, int] = (12, 12), cmap: Optional[str] = "gray"
+) -> None:
     """
-    Display a frame in Jupyter Notebook using Matplotlib
+    Plots image using matplotlib.
 
-    Attributes:
-        frame (np.ndarray): The frame to be displayed.
-        size (Tuple[int, int]): The size of the plot. default:(10,10)
-        cmap (str): the colormap to use for single channel images. default:gray
+    Args:
+        image (np.ndarray): The frame to be displayed.
+        size (Tuple[int, int]): The size of the plot.
+        cmap (str): the colormap to use for single channel images.
 
     Examples:
         ```python
-        >>> from supervision.notebook.utils import show_frame_in_notebook
+        >>> import cv2
+        >>> import supervision as sv
+
+        >>> image = cv2.imread("path/to/image.jpg")
 
         %matplotlib inline
-        show_frame_in_notebook(frame, (16, 16))
+        >>> sv.plot_image(image, (16, 16))
         ```
     """
-    if frame.ndim == 2:
-        plt.figure(figsize=size)
-        plt.imshow(frame, cmap=cmap)
+    plt.figure(figsize=size)
+
+    if image.ndim == 2:
+        plt.imshow(image, cmap=cmap)
     else:
-        plt.figure(figsize=size)
-        plt.imshow(cv2.cvtColor(frame, cv2.COLOR_BGR2RGB))
+        plt.imshow(cv2.cvtColor(image, cv2.COLOR_BGR2RGB))
+
+    plt.axis("off")
+    plt.show()
+
+
+def plot_images_grid(
+    images: List[np.ndarray],
+    grid_size: Tuple[int, int],
+    titles: Optional[List[str]] = None,
+    size: Tuple[int, int] = (12, 12),
+    cmap: Optional[str] = "gray",
+) -> None:
+    """
+    Plots images in a grid using matplotlib.
+
+    Args:
+       images (List[np.ndarray]): A list of images as numpy arrays.
+       grid_size (Tuple[int, int]): A tuple specifying the number of rows and columns for the grid.
+       titles (Optional[List[str]]): A list of titles for each image. Defaults to None.
+       size (Tuple[int, int]): A tuple specifying the width and height of the entire plot in inches.
+       cmap (str): the colormap to use for single channel images.
+
+    Raises:
+       ValueError: If the number of images exceeds the grid size.
+
+    Examples:
+        ```python
+        >>> import cv2
+        >>> import supervision as sv
+
+        >>> image1 = cv2.imread("path/to/image1.jpg")
+        >>> image2 = cv2.imread("path/to/image2.jpg")
+        >>> image3 = cv2.imread("path/to/image3.jpg")
+
+        >>> images = [image1, image2, image3]
+        >>> titles = ["Image 1", "Image 2", "Image 3"]
+
+        %matplotlib inline
+        >>> plot_images_grid(images, grid_size=(2, 2), titles=titles, figsize=(16, 16))
+        ```
+    """
+    nrows, ncols = grid_size
+
+    if len(images) > nrows * ncols:
+        raise ValueError(
+            "The number of images exceeds the grid size. Please increase the grid size or reduce the number of images."
+        )
+
+    fig, axes = plt.subplots(nrows=nrows, ncols=ncols, figsize=size)
+
+    for idx, ax in enumerate(axes.flat):
+        if idx < len(images):
+            if images[idx].ndim == 2:
+                ax.imshow(images[idx], cmap=cmap)
+            else:
+                ax.imshow(cv2.cvtColor(images[idx], cv2.COLOR_BGR2RGB))
+
+            if titles is not None and idx < len(titles):
+                ax.set_title(titles[idx])
+
+        ax.axis("off")
     plt.show()