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comments	description	keywords
true	Advanced Data Visualization with Ultralytics YOLOv8 Heatmaps	Ultralytics, YOLOv8, Advanced Data Visualization, Heatmap Technology, Object Detection and Tracking, Jupyter Notebook, Python SDK, Command Line Interface

Advanced Data Visualization: Heatmaps using Ultralytics YOLOv8 🚀

Introduction to Heatmaps

A heatmap generated with Ultralytics YOLOv8 transforms complex data into a vibrant, color-coded matrix. This visual tool employs a spectrum of colors to represent varying data values, where warmer hues indicate higher intensities and cooler tones signify lower values. Heatmaps excel in visualizing intricate data patterns, correlations, and anomalies, offering an accessible and engaging approach to data interpretation across diverse domains.

Why Choose Heatmaps for Data Analysis?

Intuitive Data Distribution Visualization: Heatmaps simplify the comprehension of data concentration and distribution, converting complex datasets into easy-to-understand visual formats.
Efficient Pattern Detection: By visualizing data in heatmap format, it becomes easier to spot trends, clusters, and outliers, facilitating quicker analysis and insights.
Enhanced Spatial Analysis and Decision Making: Heatmaps are instrumental in illustrating spatial relationships, aiding in decision-making processes in sectors such as business intelligence, environmental studies, and urban planning.

Real World Applications

Transportation	Retail

Ultralytics YOLOv8 Transportation Heatmap	Ultralytics YOLOv8 Retail Heatmap

???+ tip "heatmap_alpha"

heatmap_alpha value should be in range (0.0 - 1.0)

???+ tip "decay_factor"

Used for removal of heatmap after object removed from frame, value should be in range (0.0 - 1.0)

!!! Example "Heatmaps using Ultralytics YOLOv8 Example"

=== "Heatmap"
    ```python
    from ultralytics import YOLO
    from ultralytics.solutions import heatmap
    import cv2

    model = YOLO("yolov8n.pt")
    cap = cv2.VideoCapture("path/to/video/file.mp4")
    assert cap.isOpened(), "Error reading video file"

    # Video writer
    video_writer = cv2.VideoWriter("heatmap_output.avi",
                                   cv2.VideoWriter_fourcc(*'mp4v'),
                                   int(cap.get(5)),
                                   (int(cap.get(3)), int(cap.get(4))))

    # Init heatmap
    heatmap_obj = heatmap.Heatmap()
    heatmap_obj.set_args(colormap=cv2.COLORMAP_PARULA ,
                         imw=cap.get(4),  # should same as cap height
                         imh=cap.get(3),  # should same as cap width
                         view_img=True,
                         shape="circle")

    while cap.isOpened():
        success, im0 = cap.read()
        if not success:
            print("Video frame is empty or video processing has been successfully completed.")
            break
        tracks = model.track(im0, persist=True, show=False)

        im0 = heatmap_obj.generate_heatmap(im0, tracks)
        video_writer.write(im0)

    cap.release()
    video_writer.release()
    cv2.destroyAllWindows()

    ```

=== "Line Counting"
    ```python
    from ultralytics import YOLO
    from ultralytics.solutions import heatmap
    import cv2

    model = YOLO("yolov8n.pt")
    cap = cv2.VideoCapture("path/to/video/file.mp4")
    assert cap.isOpened(), "Error reading video file"

    # Video writer
    video_writer = cv2.VideoWriter("heatmap_output.avi",
                                   cv2.VideoWriter_fourcc(*'mp4v'),
                                   int(cap.get(5)),
                                   (int(cap.get(3)), int(cap.get(4))))

    line_points = [(256, 409), (694, 532)]  # line for object counting

    # Init heatmap
    heatmap_obj = heatmap.Heatmap()
    heatmap_obj.set_args(colormap=cv2.COLORMAP_PARULA ,
                         imw=cap.get(4),  # should same as cap height
                         imh=cap.get(3),  # should same as cap width
                         view_img=True,
                         shape="circle",
                         count_reg_pts=line_points)

    while cap.isOpened():
        success, im0 = cap.read()
        if not success:
            print("Video frame is empty or video processing has been successfully completed.")
            break
        tracks = model.track(im0, persist=True, show=False)

        im0 = heatmap_obj.generate_heatmap(im0, tracks)
        video_writer.write(im0)

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

=== "Region Counting"
    ```python
    from ultralytics import YOLO
    from ultralytics.solutions import heatmap
    import cv2

    model = YOLO("yolov8n.pt")
    cap = cv2.VideoCapture("path/to/video/file.mp4")
    assert cap.isOpened(), "Error reading video file"

    # Video writer
    video_writer = cv2.VideoWriter("heatmap_output.avi",
                                   cv2.VideoWriter_fourcc(*'mp4v'),
                                   int(cap.get(5)),
                                   (int(cap.get(3)), int(cap.get(4))))

    # Define region points
    region_points = [(20, 400), (1080, 404), (1080, 360), (20, 360)]

    # Init heatmap
    heatmap_obj = heatmap.Heatmap()
    heatmap_obj.set_args(colormap=cv2.COLORMAP_PARULA ,
                         imw=cap.get(4),  # should same as cap height
                         imh=cap.get(3),  # should same as cap width
                         view_img=True,
                         shape="circle",
                         count_reg_pts=region_points)

    while cap.isOpened():
        success, im0 = cap.read()
        if not success:
            print("Video frame is empty or video processing has been successfully completed.")
            break
        tracks = model.track(im0, persist=True, show=False)

        im0 = heatmap_obj.generate_heatmap(im0, tracks)
        video_writer.write(im0)

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

=== "Im0"
    ```python
    from ultralytics import YOLO
    from ultralytics.solutions import heatmap
    import cv2

    model = YOLO("yolov8s.pt")   # YOLOv8 custom/pretrained model

    im0 = cv2.imread("path/to/image.png")  # path to image file

    # Heatmap Init
    heatmap_obj = heatmap.Heatmap()
    heatmap_obj.set_args(colormap=cv2.COLORMAP_PARULA ,
                                 imw=cap.get(4),  # should same as cap height
                                 imh=cap.get(3),  # should same as cap width
                                 view_img=True,
                                 shape="circle")


    results = model.track(im0, persist=True)
    im0 = heatmap_obj.generate_heatmap(im0, tracks=results)
    cv2.imwrite("ultralytics_output.png", im0)
    ```

=== "Specific Classes"
    ```python
    from ultralytics import YOLO
    from ultralytics.solutions import heatmap
    import cv2

    model = YOLO("yolov8n.pt")
    cap = cv2.VideoCapture("path/to/video/file.mp4")
    assert cap.isOpened(), "Error reading video file"

    # Video writer
    video_writer = cv2.VideoWriter("heatmap_output.avi",
                                   cv2.VideoWriter_fourcc(*'mp4v'),
                                   int(cap.get(5)),
                                   (int(cap.get(3)), int(cap.get(4))))

    classes_for_heatmap = [0, 2]  # classes for heatmap

    # Init heatmap
    heatmap_obj = heatmap.Heatmap()
    heatmap_obj.set_args(colormap=cv2.COLORMAP_PARULA ,
                         imw=cap.get(4),  # should same as cap height
                         imh=cap.get(3),  # should same as cap width
                         view_img=True,
                         shape="circle")

    while cap.isOpened():
        success, im0 = cap.read()
        if not success:
            print("Video frame is empty or video processing has been successfully completed.")
            break
        tracks = model.track(im0, persist=True, show=False,
                             classes=classes_for_heatmap)

        im0 = heatmap_obj.generate_heatmap(im0, tracks)
        video_writer.write(im0)

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

Arguments `set_args`

Name	Type	Default	Description
view_img	`bool`	`False`	Display the frame with heatmap
colormap	`cv2.COLORMAP`	`None`	cv2.COLORMAP for heatmap
imw	`int`	`None`	Width of Heatmap
imh	`int`	`None`	Height of Heatmap
heatmap_alpha	`float`	`0.5`	Heatmap alpha value
count_reg_pts	`list`	`None`	Object counting region points
count_txt_thickness	`int`	`2`	Count values text size
count_txt_color	`RGB Color`	`(0, 0, 0)`	Foreground color for Object counts text
count_color	`RGB Color`	`(255, 255, 255)`	Background color for Object counts text
count_reg_color	`RGB Color`	`(255, 0, 255)`	Counting region color
region_thickness	`int`	`5`	Counting region thickness value
decay_factor	`float`	`0.99`	Decay factor for heatmap area removal after specific time
shape	`str`	`circle`	Heatmap shape for display "rect" or "circle" supported
line_dist_thresh	`int`	`15`	Euclidean Distance threshold for line counter

Arguments `model.track`

Name	Type	Default	Description
`source`	`im0`	`None`	source directory for images or videos
`persist`	`bool`	`False`	persisting tracks between frames
`tracker`	`str`	`botsort.yaml`	Tracking method 'bytetrack' or 'botsort'
`conf`	`float`	`0.3`	Confidence Threshold
`iou`	`float`	`0.5`	IOU Threshold
`classes`	`list`	`None`	filter results by class, i.e. classes=0, or classes=[0,2,3]

Heatmap COLORMAPs

Colormap Name	Description
`cv::COLORMAP_AUTUMN`	Autumn color map
`cv::COLORMAP_BONE`	Bone color map
`cv::COLORMAP_JET`	Jet color map
`cv::COLORMAP_WINTER`	Winter color map
`cv::COLORMAP_RAINBOW`	Rainbow color map
`cv::COLORMAP_OCEAN`	Ocean color map
`cv::COLORMAP_SUMMER`	Summer color map
`cv::COLORMAP_SPRING`	Spring color map
`cv::COLORMAP_COOL`	Cool color map
`cv::COLORMAP_HSV`	HSV (Hue, Saturation, Value) color map
`cv::COLORMAP_PINK`	Pink color map
`cv::COLORMAP_HOT`	Hot color map
`cv::COLORMAP_PARULA`	Parula color map
`cv::COLORMAP_MAGMA`	Magma color map
`cv::COLORMAP_INFERNO`	Inferno color map
`cv::COLORMAP_PLASMA`	Plasma color map
`cv::COLORMAP_VIRIDIS`	Viridis color map
`cv::COLORMAP_CIVIDIS`	Cividis color map
`cv::COLORMAP_TWILIGHT`	Twilight color map
`cv::COLORMAP_TWILIGHT_SHIFTED`	Shifted Twilight color map
`cv::COLORMAP_TURBO`	Turbo color map
`cv::COLORMAP_DEEPGREEN`	Deep Green color map

These colormaps are commonly used for visualizing data with different color representations.

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