ultralytics/docs/en/guides/instance-segmentation-and-t...

---
comments: true
description: Master instance segmentation and tracking with Ultralytics YOLOv8. Learn techniques for precise object identification and tracking.
keywords: instance segmentation, tracking, YOLOv8, Ultralytics, object detection, machine learning, computer vision, python
---

# Instance Segmentation and Tracking using Ultralytics YOLOv8 🚀

## What is Instance Segmentation?

[Ultralytics YOLOv8](https://github.com/ultralytics/ultralytics/) instance segmentation involves identifying and outlining individual objects in an image, providing a detailed understanding of spatial distribution. Unlike semantic segmentation, it uniquely labels and precisely delineates each object, crucial for tasks like object detection and medical imaging.

There are two types of instance segmentation tracking available in the Ultralytics package:

- **Instance Segmentation with Class Objects:** Each class object is assigned a unique color for clear visual separation.

- **Instance Segmentation with Object Tracks:** Every track is represented by a distinct color, facilitating easy identification and tracking.

<p align="center">
  <br>
  <iframe loading="lazy" width="720" height="405" src="https://www.youtube.com/embed/75G_S1Ngji8"
    title="YouTube video player" frameborder="0"
    allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share"
    allowfullscreen>
  </iframe>
  <br>
  <strong>Watch:</strong> Instance Segmentation with Object Tracking using Ultralytics YOLOv8
</p>

## Samples

|                                                          Instance Segmentation                                                          |                                                           Instance Segmentation + Object Tracking                                                            |
| :-------------------------------------------------------------------------------------------------------------------------------------: | :----------------------------------------------------------------------------------------------------------------------------------------------------------: |
| ![Ultralytics Instance Segmentation](https://github.com/RizwanMunawar/ultralytics/assets/62513924/d4ad3499-1f33-4871-8fbc-1be0b2643aa2) | ![Ultralytics Instance Segmentation with Object Tracking](https://github.com/RizwanMunawar/ultralytics/assets/62513924/2e5c38cc-fd5c-4145-9682-fa94ae2010a0) |
|                                                  Ultralytics Instance Segmentation 😍                                                   |                                                  Ultralytics Instance Segmentation with Object Tracking 🔥                                                   |

!!! Example "Instance Segmentation and Tracking"

    === "Instance Segmentation"

        ```python
        import cv2

        from ultralytics import YOLO
        from ultralytics.utils.plotting import Annotator, colors

        model = YOLO("yolov8n-seg.pt")  # segmentation model
        names = model.model.names
        cap = cv2.VideoCapture("path/to/video/file.mp4")
        w, h, fps = (int(cap.get(x)) for x in (cv2.CAP_PROP_FRAME_WIDTH, cv2.CAP_PROP_FRAME_HEIGHT, cv2.CAP_PROP_FPS))

        out = cv2.VideoWriter("instance-segmentation.avi", cv2.VideoWriter_fourcc(*"MJPG"), fps, (w, h))

        while True:
            ret, im0 = cap.read()
            if not ret:
                print("Video frame is empty or video processing has been successfully completed.")
                break

            results = model.predict(im0)
            annotator = Annotator(im0, line_width=2)

            if results[0].masks is not None:
                clss = results[0].boxes.cls.cpu().tolist()
                masks = results[0].masks.xy
                for mask, cls in zip(masks, clss):
                    color = colors(int(cls), True)
                    txt_color = annotator.get_txt_color(color)
                    annotator.seg_bbox(mask=mask, mask_color=color, label=names[int(cls)], txt_color=txt_color)

            out.write(im0)
            cv2.imshow("instance-segmentation", im0)

            if cv2.waitKey(1) & 0xFF == ord("q"):
                break

        out.release()
        cap.release()
        cv2.destroyAllWindows()
        ```

    === "Instance Segmentation with Object Tracking"

        ```python
        from collections import defaultdict

        import cv2

        from ultralytics import YOLO
        from ultralytics.utils.plotting import Annotator, colors

        track_history = defaultdict(lambda: [])

        model = YOLO("yolov8n-seg.pt")  # segmentation model
        cap = cv2.VideoCapture("path/to/video/file.mp4")
        w, h, fps = (int(cap.get(x)) for x in (cv2.CAP_PROP_FRAME_WIDTH, cv2.CAP_PROP_FRAME_HEIGHT, cv2.CAP_PROP_FPS))

        out = cv2.VideoWriter("instance-segmentation-object-tracking.avi", cv2.VideoWriter_fourcc(*"MJPG"), fps, (w, h))

        while True:
            ret, im0 = cap.read()
            if not ret:
                print("Video frame is empty or video processing has been successfully completed.")
                break

            annotator = Annotator(im0, line_width=2)

            results = model.track(im0, persist=True)

            if results[0].boxes.id is not None and results[0].masks is not None:
                masks = results[0].masks.xy
                track_ids = results[0].boxes.id.int().cpu().tolist()

                for mask, track_id in zip(masks, track_ids):
                    color = colors(int(track_id), True)
                    txt_color = annotator.get_txt_color(color)
                    annotator.seg_bbox(mask=mask, mask_color=color, label=str(track_id), txt_color=txt_color)

            out.write(im0)
            cv2.imshow("instance-segmentation-object-tracking", im0)

            if cv2.waitKey(1) & 0xFF == ord("q"):
                break

        out.release()
        cap.release()
        cv2.destroyAllWindows()
        ```

### `seg_bbox` Arguments

| Name         | Type    | Default         | Description                                  |
| ------------ | ------- | --------------- | -------------------------------------------- |
| `mask`       | `array` | `None`          | Segmentation mask coordinates                |
| `mask_color` | `RGB`   | `(255, 0, 255)` | Mask color for every segmented box           |
| `label`      | `str`   | `None`          | Label for segmented object                   |
| `txt_color`  | `RGB`   | `None`          | Label color for segmented and tracked object |

## Note

For any inquiries, feel free to post your questions in the [Ultralytics Issue Section](https://github.com/ultralytics/ultralytics/issues/new/choose) or the discussion section mentioned below.

## FAQ

### How do I perform instance segmentation using Ultralytics YOLOv8?

To perform instance segmentation using Ultralytics YOLOv8, initialize the YOLO model with a segmentation version of YOLOv8 and process video frames through it. Here's a simplified code example:

!!! Example

    === "Python"

        ```python
        import cv2

        from ultralytics import YOLO
        from ultralytics.utils.plotting import Annotator, colors

        model = YOLO("yolov8n-seg.pt")  # segmentation model
        cap = cv2.VideoCapture("path/to/video/file.mp4")
        w, h, fps = (int(cap.get(x)) for x in (cv2.CAP_PROP_FRAME_WIDTH, cv2.CAP_PROP_FRAME_HEIGHT, cv2.CAP_PROP_FPS))

        out = cv2.VideoWriter("instance-segmentation.avi", cv2.VideoWriter_fourcc(*"MJPG"), fps, (w, h))

        while True:
            ret, im0 = cap.read()
            if not ret:
                break

            results = model.predict(im0)
            annotator = Annotator(im0, line_width=2)

            if results[0].masks is not None:
                clss = results[0].boxes.cls.cpu().tolist()
                masks = results[0].masks.xy
                for mask, cls in zip(masks, clss):
                    annotator.seg_bbox(mask=mask, mask_color=colors(int(cls), True), det_label=model.model.names[int(cls)])

            out.write(im0)
            cv2.imshow("instance-segmentation", im0)
            if cv2.waitKey(1) & 0xFF == ord("q"):
                break

        out.release()
        cap.release()
        cv2.destroyAllWindows()
        ```

Learn more about instance segmentation in the [Ultralytics YOLOv8 guide](#what-is-instance-segmentation).

### What is the difference between instance segmentation and object tracking in Ultralytics YOLOv8?

Instance segmentation identifies and outlines individual objects within an image, giving each object a unique label and mask. Object tracking extends this by assigning consistent labels to objects across video frames, facilitating continuous tracking of the same objects over time. Learn more about the distinctions in the [Ultralytics YOLOv8 documentation](#samples).

### Why should I use Ultralytics YOLOv8 for instance segmentation and tracking over other models like Mask R-CNN or Faster R-CNN?

Ultralytics YOLOv8 offers real-time performance, superior accuracy, and ease of use compared to other models like Mask R-CNN or Faster R-CNN. YOLOv8 provides a seamless integration with Ultralytics HUB, allowing users to manage models, datasets, and training pipelines efficiently. Discover more about the benefits of YOLOv8 in the [Ultralytics blog](https://www.ultralytics.com/blog/introducing-ultralytics-yolov8).

### How can I implement object tracking using Ultralytics YOLOv8?

To implement object tracking, use the `model.track` method and ensure that each object's ID is consistently assigned across frames. Below is a simple example:

!!! Example

    === "Python"

        ```python
        from collections import defaultdict

        import cv2

        from ultralytics import YOLO
        from ultralytics.utils.plotting import Annotator, colors

        track_history = defaultdict(lambda: [])

        model = YOLO("yolov8n-seg.pt")  # segmentation model
        cap = cv2.VideoCapture("path/to/video/file.mp4")
        w, h, fps = (int(cap.get(x)) for x in (cv2.CAP_PROP_FRAME_WIDTH, cv2.CAP_PROP_FRAME_HEIGHT, cv2.CAP_PROP_FPS))

        out = cv2.VideoWriter("instance-segmentation-object-tracking.avi", cv2.VideoWriter_fourcc(*"MJPG"), fps, (w, h))

        while True:
            ret, im0 = cap.read()
            if not ret:
                break

            annotator = Annotator(im0, line_width=2)
            results = model.track(im0, persist=True)

            if results[0].boxes.id is not None and results[0].masks is not None:
                masks = results[0].masks.xy
                track_ids = results[0].boxes.id.int().cpu().tolist()

                for mask, track_id in zip(masks, track_ids):
                    annotator.seg_bbox(mask=mask, mask_color=colors(track_id, True), track_label=str(track_id))

            out.write(im0)
            cv2.imshow("instance-segmentation-object-tracking", im0)
            if cv2.waitKey(1) & 0xFF == ord("q"):
                break

        out.release()
        cap.release()
        cv2.destroyAllWindows()
        ```

Find more in the [Instance Segmentation and Tracking section](#samples).

### Are there any datasets provided by Ultralytics suitable for training YOLOv8 models for instance segmentation and tracking?

Yes, Ultralytics offers several datasets suitable for training YOLOv8 models, including segmentation and tracking datasets. Dataset examples, structures, and instructions for use can be found in the [Ultralytics Datasets documentation](https://docs.ultralytics.com/datasets/).