ultralytics/solutions/streamlit_inference.py

# Ultralytics 🚀 AGPL-3.0 License - https://ultralytics.com/license

import io
from typing import Any

import cv2

from ultralytics import YOLO
from ultralytics.utils import LOGGER
from ultralytics.utils.checks import check_requirements
from ultralytics.utils.downloads import GITHUB_ASSETS_STEMS


class Inference:
    """
    A class to perform object detection, image classification, image segmentation and pose estimation inference using
    Streamlit and Ultralytics YOLO models. It provides the functionalities such as loading models, configuring settings,
    uploading video files, and performing real-time inference.

    Attributes:
        st (module): Streamlit module for UI creation.
        temp_dict (dict): Temporary dictionary to store the model path.
        model_path (str): Path to the loaded model.
        model (YOLO): The YOLO model instance.
        source (str): Selected video source.
        enable_trk (str): Enable tracking option.
        conf (float): Confidence threshold.
        iou (float): IoU threshold for non-max suppression.
        vid_file_name (str): Name of the uploaded video file.
        selected_ind (list): List of selected class indices.

    Methods:
        web_ui: Sets up the Streamlit web interface with custom HTML elements.
        sidebar: Configures the Streamlit sidebar for model and inference settings.
        source_upload: Handles video file uploads through the Streamlit interface.
        configure: Configures the model and loads selected classes for inference.
        inference: Performs real-time object detection inference.

    Examples:
        >>> inf = solutions.Inference(model="path/to/model.pt")  # Model is not necessary argument.
        >>> inf.inference()
    """

    def __init__(self, **kwargs: Any):
        """
        Initializes the Inference class, checking Streamlit requirements and setting up the model path.

        Args:
            **kwargs (Any): Additional keyword arguments for model configuration.
        """
        check_requirements("streamlit>=1.29.0")  # scope imports for faster ultralytics package load speeds
        import streamlit as st

        self.st = st  # Reference to the Streamlit class instance
        self.source = None  # Placeholder for video or webcam source details
        self.enable_trk = False  # Flag to toggle object tracking
        self.conf = 0.25  # Confidence threshold for detection
        self.iou = 0.45  # Intersection-over-Union (IoU) threshold for non-maximum suppression
        self.org_frame = None  # Container for the original frame to be displayed
        self.ann_frame = None  # Container for the annotated frame to be displayed
        self.vid_file_name = None  # Holds the name of the video file
        self.selected_ind = []  # List of selected classes for detection or tracking
        self.model = None  # Container for the loaded model instance

        self.temp_dict = {"model": None, **kwargs}
        self.model_path = None  # Store model file name with path
        if self.temp_dict["model"] is not None:
            self.model_path = self.temp_dict["model"]

        LOGGER.info(f"Ultralytics Solutions: ✅ {self.temp_dict}")

    def web_ui(self):
        """Sets up the Streamlit web interface with custom HTML elements."""
        menu_style_cfg = """<style>MainMenu {visibility: hidden;}</style>"""  # Hide main menu style

        # Main title of streamlit application
        main_title_cfg = """<div><h1 style="color:#FF64DA; text-align:center; font-size:40px; margin-top:-50px;
        font-family: 'Archivo', sans-serif; margin-bottom:20px;">Ultralytics YOLO Streamlit Application</h1></div>"""

        # Subtitle of streamlit application
        sub_title_cfg = """<div><h4 style="color:#042AFF; text-align:center; font-family: 'Archivo', sans-serif; 
        margin-top:-15px; margin-bottom:50px;">Experience real-time object detection on your webcam with the power 
        of Ultralytics YOLO! 🚀</h4></div>"""

        # Set html page configuration and append custom HTML
        self.st.set_page_config(page_title="Ultralytics Streamlit App", layout="wide")
        self.st.markdown(menu_style_cfg, unsafe_allow_html=True)
        self.st.markdown(main_title_cfg, unsafe_allow_html=True)
        self.st.markdown(sub_title_cfg, unsafe_allow_html=True)

    def sidebar(self):
        """Configures the Streamlit sidebar for model and inference settings."""
        with self.st.sidebar:  # Add Ultralytics LOGO
            logo = "https://raw.githubusercontent.com/ultralytics/assets/main/logo/Ultralytics_Logotype_Original.svg"
            self.st.image(logo, width=250)

        self.st.sidebar.title("User Configuration")  # Add elements to vertical setting menu
        self.source = self.st.sidebar.selectbox(
            "Video",
            ("webcam", "video"),
        )  # Add source selection dropdown
        self.enable_trk = self.st.sidebar.radio("Enable Tracking", ("Yes", "No"))  # Enable object tracking
        self.conf = float(
            self.st.sidebar.slider("Confidence Threshold", 0.0, 1.0, self.conf, 0.01)
        )  # Slider for confidence
        self.iou = float(self.st.sidebar.slider("IoU Threshold", 0.0, 1.0, self.iou, 0.01))  # Slider for NMS threshold

        col1, col2 = self.st.columns(2)
        self.org_frame = col1.empty()
        self.ann_frame = col2.empty()

    def source_upload(self):
        """Handles video file uploads through the Streamlit interface."""
        self.vid_file_name = ""
        if self.source == "video":
            vid_file = self.st.sidebar.file_uploader("Upload Video File", type=["mp4", "mov", "avi", "mkv"])
            if vid_file is not None:
                g = io.BytesIO(vid_file.read())  # BytesIO Object
                with open("ultralytics.mp4", "wb") as out:  # Open temporary file as bytes
                    out.write(g.read())  # Read bytes into file
                self.vid_file_name = "ultralytics.mp4"
        elif self.source == "webcam":
            self.vid_file_name = 0

    def configure(self):
        """Configures the model and loads selected classes for inference."""
        # Add dropdown menu for model selection
        available_models = [x.replace("yolo", "YOLO") for x in GITHUB_ASSETS_STEMS if x.startswith("yolo11")]
        if self.model_path:  # If user provided the custom model, insert model without suffix as *.pt is added later
            available_models.insert(0, self.model_path.split(".pt")[0])
        selected_model = self.st.sidebar.selectbox("Model", available_models)

        with self.st.spinner("Model is downloading..."):
            self.model = YOLO(f"{selected_model.lower()}.pt")  # Load the YOLO model
            class_names = list(self.model.names.values())  # Convert dictionary to list of class names
        self.st.success("Model loaded successfully!")

        # Multiselect box with class names and get indices of selected classes
        selected_classes = self.st.sidebar.multiselect("Classes", class_names, default=class_names[:3])
        self.selected_ind = [class_names.index(option) for option in selected_classes]

        if not isinstance(self.selected_ind, list):  # Ensure selected_options is a list
            self.selected_ind = list(self.selected_ind)

    def inference(self):
        """Performs real-time object detection inference."""
        self.web_ui()  # Initialize the web interface
        self.sidebar()  # Create the sidebar
        self.source_upload()  # Upload the video source
        self.configure()  # Configure the app

        if self.st.sidebar.button("Start"):
            stop_button = self.st.button("Stop")  # Button to stop the inference
            cap = cv2.VideoCapture(self.vid_file_name)  # Capture the video
            if not cap.isOpened():
                self.st.error("Could not open webcam.")
            while cap.isOpened():
                success, frame = cap.read()
                if not success:
                    self.st.warning("Failed to read frame from webcam. Please verify the webcam is connected properly.")
                    break

                # Store model predictions
                if self.enable_trk == "Yes":
                    results = self.model.track(
                        frame, conf=self.conf, iou=self.iou, classes=self.selected_ind, persist=True
                    )
                else:
                    results = self.model(frame, conf=self.conf, iou=self.iou, classes=self.selected_ind)
                annotated_frame = results[0].plot()  # Add annotations on frame

                if stop_button:
                    cap.release()  # Release the capture
                    self.st.stop()  # Stop streamlit app

                self.org_frame.image(frame, channels="BGR")  # Display original frame
                self.ann_frame.image(annotated_frame, channels="BGR")  # Display processed frame

            cap.release()  # Release the capture
        cv2.destroyAllWindows()  # Destroy window


if __name__ == "__main__":
    import sys  # Import the sys module for accessing command-line arguments

    # Check if a model name is provided as a command-line argument
    args = len(sys.argv)
    model = sys.argv[1] if args > 1 else None  # assign first argument as the model name
    # Create an instance of the Inference class and run inference
    Inference(model=model).inference()