app.py

import gradio as gr
import cv2
import random
import os
import tempfile
import numpy as np
import yt_dlp

def get_random_frame(youtube_url):
    """
    Downloads a video from YouTube and returns a random frame.
    """
    if not youtube_url:
        raise gr.Error("Please provide a valid YouTube URL.")
    
    # Create a temporary directory for the download
    temp_dir = tempfile.mkdtemp()
    
    try:
        # Configure yt-dlp options
        ydl_opts = {
            'format': 'best[ext=mp4]/best', # Prefer MP4 for better OpenCV compatibility
            'outtmpl': os.path.join(temp_dir, '%(id)s.%(ext)s'),
            'quiet': True,
            'no_warnings': True,
        }

        # Download video info first to check validity
        with yt_dlp.YoutubeDL(ydl_opts) as ydl:
            try:
                info = ydl.extract_info(youtube_url, download=False)
                if 'duration' not in info:
                    raise gr.Error("Could not retrieve video duration. The video might be private or a live stream.")
            except Exception as e:
                raise gr.Error(f"Invalid YouTube URL or Video unavailable: {str(e)}")

            # Download the video
            ydl.params['quiet'] = False # Show progress
            info = ydl.extract_info(youtube_url, download=True)
            video_path = ydl.prepare_filename(info)

        # Open the video file using OpenCV
        cap = cv2.VideoCapture(video_path)
        
        if not cap.isOpened():
            raise gr.Error("Could not open the video file after downloading.")

        # Get total number of frames
        total_frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
        
        if total_frames == 0:
            raise gr.Error("Video has no frames.")

        # Select a random frame index
        random_frame_idx = random.randint(0, total_frames - 1)
        
        # Set the frame position
        cap.set(cv2.CAP_PROP_POS_FRAMES, random_frame_idx)
        
        # Read the frame
        ret, frame = cap.read()
        
        cap.release()
        
        if not ret:
            raise gr.Error("Failed to read the selected frame.")

        # Convert BGR (OpenCV default) to RGB (Gradio/Image default)
        frame_rgb = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
        
        return frame_rgb

    except gr.Error:
        raise
    except Exception as e:
        raise gr.Error(f"An unexpected error occurred: {str(e)}")
    finally:
        # Clean up temporary files
        import shutil
        if os.path.exists(temp_dir):
            shutil.rmtree(temp_dir, ignore_errors=True)

# Gradio 6 Application
with gr.Blocks() as demo:
    
    # Header with required link
    gr.HTML("""
    <div style="text-align: center; margin-bottom: 20px;">
        <h1>YouTube Frame Randomizer</h1>
        <p>Enter a YouTube URL to extract a random frame from the video.</p>
        <a href="https://huggingface.co/spaces/akhaliq/anycoder" target="_blank" style="color: #007bff; text-decoration: none; font-weight: bold;">Built with anycoder</a>
    </div>
    """)

    with gr.Row():
        with gr.Column(scale=1):
            url_input = gr.Textbox(
                label="YouTube URL",
                placeholder="https://www.youtube.com/watch?v=...",
                lines=1
            )
            randomize_btn = gr.Button("Get Random Frame", variant="primary", size="lg")
            
            gr.Markdown("""
            ### How it works:
            1. Paste a YouTube link.
            2. Click the button.
            3. The app downloads the video (this may take a moment).
            4. A random timestamp is selected and the frame is displayed.
            """)

        with gr.Column(scale=2):
            output_image = gr.Image(
                label="Random Frame",
                type="numpy",
                interactive=False
            )

    # Event listener
    randomize_btn.click(
        fn=get_random_frame,
        inputs=url_input,
        outputs=output_image,
        api_visibility="public"
    )

# Launch the app with Gradio 6 syntax
# Note: theme, css, and footer_links are now parameters of demo.launch()
demo.launch(
    theme=gr.themes.Soft(
        primary_hue="blue",
        secondary_hue="cyan",
    ),
    footer_links=[
        {"label": "Gradio", "url": "https://gradio.app"},
        {"label": "Hugging Face", "url": "https://huggingface.co"},
        {"label": "Built with anycoder", "url": "https://huggingface.co/spaces/akhaliq/anycoder"}
    ]
)