app.py

import random
import time
import numpy as np
import gradio as gr
import colorsys

from fastrtc import WebRTC, get_turn_credentials

def video_generation_handler(prompt):
    num_frames = 120
    width, height = 832, 480
    
    for frame_idx in range(num_frames): 
        hue = (frame_idx * 3) % 360
        saturation = 0.7 + 0.3 * np.sin(frame_idx * 0.1)
        value = 0.8 + 0.2 * np.sin(frame_idx * 0.2)
        
        r, g, b = colorsys.hsv_to_rgb(hue/360, saturation, value)
        
        rgb_frame = np.full((height, width, 3), [r*255, g*255, b*255], dtype=np.uint8)
        
        noise = np.random.randint(-15, 15, (height, width, 3), dtype=np.int16)
        rgb_frame = np.clip(rgb_frame.astype(np.int16) + noise, 0, 255).astype(np.uint8)
        
        x_grad = np.linspace(0, 1, width)
        y_grad = np.linspace(0, 1, height)
        X, Y = np.meshgrid(x_grad, y_grad)
        
        wave = np.sin(X * 4 + frame_idx * 0.2) * np.sin(Y * 4 + frame_idx * 0.3)
        wave_normalized = ((wave + 1) / 2 * 40).astype(np.uint8)
        
        rgb_frame[:, :, (frame_idx // 20) % 3] = np.clip(
            rgb_frame[:, :, (frame_idx // 20) % 3].astype(np.int16) + wave_normalized, 
            0, 255
        ).astype(np.uint8)
        
        bgr_frame = rgb_frame[:, :, ::-1]
        
        yield bgr_frame
        time.sleep(0.033) # 30 fps
    
    print("🎉 Dummy stream finished!")

# --- Gradio UI Layout ---
with gr.Blocks(theme=gr.themes.Soft(), title="Dummy FastRTC Demo") as demo:
    gr.Markdown("# 🚀 Dummy Video Generation with FastRTC Streaming")
    gr.Markdown("*This is a demo version that generates random colored frames instead of actual video content.*")
    
    with gr.Row():
        with gr.Column(scale=2):
            gr.Markdown("### 1. Configure Generation")
            with gr.Group():
                prompt = gr.Textbox(
                    label="Prompt", 
                    placeholder="Enter any prompt to change the random seed", 
                    lines=3,
                    value="A colorful animated demo"
                )
            
            start = gr.Button("🚀 Start Generation", variant="primary")
            
        with gr.Column(scale=3):
            gr.Markdown("### 2. View Live Stream")
            gr.Markdown("Click 'Start Generation' to begin streaming frames.")
            
            webrtc_output = WebRTC(
                label="Video Stream",
                modality="video", 
                mode="receive",
                height=480,
                rtc_configuration=get_turn_credentials(),
            )
        
    webrtc_output.stream(
        fn=video_generation_handler, 
        inputs=[prompt],
        outputs=[webrtc_output],
        time_limit=120,
        trigger=start.click
    )

if __name__ == "__main__":
    demo.queue().launch(share=True)