import gradio as gr
import cv2
import numpy as np

def process_video(video_path, frame_difference, brightness_value):
    # Read the video
    cap = cv2.VideoCapture(video_path)
    if not cap.isOpened():
        return "Error: Unable to open video."

    # Get video properties
    frame_width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
    frame_height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
    fps = int(cap.get(cv2.CAP_PROP_FPS))
    
    # Create a VideoWriter object to write the output video
    output_path = "output_video.mp4"
    out = cv2.VideoWriter(output_path, cv2.VideoWriter_fourcc(*'mp4v'), fps, (frame_width, frame_height))

    # Initialize a list to store frames for frame shifting
    frames = []
    
    while True:
        ret, frame = cap.read()
        if not ret:
            break
        # Invert the pixel values of the frame
        inverted_frame = cv2.bitwise_not(frame)
        frames.append((frame, inverted_frame))

    cap.release()

    # Calculate number of frames to process (Original length minus frame difference)
    num_frames = len(frames) - frame_difference
    num_frames = max(num_frames, 0)  # Ensure non-negative

    # Process video by applying frame difference and overlaying
    for i in range(num_frames):
        # Get the original and shifted frames
        orig_frame = frames[i][0]
        shifted_index = (i + frame_difference) % len(frames)
        shifted_frame = frames[shifted_index][1]  # Use the inverted frame of shifted frame

        # Overlay the frames with 50% opacity
        overlay_frame = cv2.addWeighted(orig_frame, 0.5, shifted_frame, 0.5, 0)

        # Increase the brightness
        overlay_frame = np.clip(overlay_frame * brightness_value, 0, 255).astype(np.uint8)

        # Write the resulting frame to the output video
        out.write(overlay_frame)

    out.release()
    
    return output_path

# Gradio Interface
iface = gr.Interface(
    fn=process_video,
    inputs=[
        gr.Video(label="Input Video"),  # Video input
        gr.Slider(0, 50, step=1, value=1, label="Frame Difference (Integer)"),  # Integer Frame difference input
        gr.Slider(0.0, 2.0, value=1.0, step=0.1, label="Brightness Adjustment (0.0 to 2.0)"),  # Brightness adjustment input
    ],
    outputs=gr.Video(label="Output Video"),  # Video output
    title="Motion Amplification with Frame Difference"
)

iface.launch()