app.py

import gradio as gr
import os
import torch
from transformers import (
    AutoTokenizer,
    AutoModelForCausalLM,
    pipeline,
    AutoProcessor,
    MusicgenForConditionalGeneration,
)
from scipy.io.wavfile import write
from pydub import AudioSegment
from dotenv import load_dotenv
import tempfile
import spaces
from TTS.api import TTS
from TTS.utils.synthesizer import Synthesizer

# Load environment variables
load_dotenv()
hf_token = os.getenv("HF_TOKEN")

# ---------------------------------------------------------------------
# Script Generation Function
# ---------------------------------------------------------------------
@spaces.GPU(duration=300)
@spaces.GPU(duration=300)
def generate_script(user_prompt: str, model_id: str, token: str, duration: int):
    try:
        tokenizer = AutoTokenizer.from_pretrained(model_id, use_auth_token=token)
        model = AutoModelForCausalLM.from_pretrained(
            model_id,
            use_auth_token=token,
            torch_dtype=torch.float16,
            device_map="auto",
            trust_remote_code=True,
        )
        llama_pipeline = pipeline("text-generation", model=model, tokenizer=tokenizer)

        # System prompt with clear structure instructions
        system_prompt = (
            f"You are an expert radio imaging producer specializing in sound design and music. "
            f"Based on the user's concept and the selected duration of {duration} seconds, produce the following: "
            f"1. A concise voice-over script. Prefix this section with 'Voice-Over Script:'.\n"
            f"2. Suggestions for sound design. Prefix this section with 'Sound Design Suggestions:'.\n"
            f"3. Music styles or track recommendations. Prefix this section with 'Music Suggestions:'."
        )

        combined_prompt = f"{system_prompt}\nUser concept: {user_prompt}\nOutput:"
        result = llama_pipeline(combined_prompt, max_new_tokens=300, do_sample=True, temperature=0.8)

        # Parsing output
        generated_text = result[0]["generated_text"].split("Output:")[-1].strip()

        # Extract sections based on prefixes
        voice_script = generated_text.split("Voice-Over Script:")[1].split("Sound Design Suggestions:")[0].strip() if "Voice-Over Script:" in generated_text else "No voice-over script found."
        sound_design = generated_text.split("Sound Design Suggestions:")[1].split("Music Suggestions:")[0].strip() if "Sound Design Suggestions:" in generated_text else "No sound design suggestions found."
        music_suggestions = generated_text.split("Music Suggestions:")[1].strip() if "Music Suggestions:" in generated_text else "No music suggestions found."

        return voice_script, sound_design, music_suggestions
    except Exception as e:
        return f"Error generating script: {e}", "", ""

# ---------------------------------------------------------------------
# Voice-Over Generation Function
# ---------------------------------------------------------------------
@spaces.GPU(duration=300)
def generate_voice(script: str, speaker: str = "default"):
    try:
        # Load TTS model
        tts_model_path = "tts_models/en/ljspeech/tacotron2-DDC"
        vocoder_model_path = "vocoder_models/en/ljspeech/hifigan_v2"
        synthesizer = Synthesizer(tts_model_path, vocoder_model_path)

        # Generate audio
        wav = synthesizer.tts(script)

        # Save output to a file
        output_path = f"{tempfile.gettempdir()}/generated_voice.wav"
        synthesizer.save_wav(wav, output_path)

        return output_path
    except Exception as e:
        return f"Error generating voice-over: {e}"

# ---------------------------------------------------------------------
# Music Generation Function
# ---------------------------------------------------------------------
@spaces.GPU(duration=300)
def generate_music(prompt: str, audio_length: int):
    try:
        musicgen_model = MusicgenForConditionalGeneration.from_pretrained("facebook/musicgen-small")
        musicgen_processor = AutoProcessor.from_pretrained("facebook/musicgen-small")

        device = "cuda" if torch.cuda.is_available() else "cpu"
        musicgen_model.to(device)

        inputs = musicgen_processor(text=[prompt], padding=True, return_tensors="pt").to(device)
        outputs = musicgen_model.generate(**inputs, max_new_tokens=audio_length)

        audio_data = outputs[0, 0].cpu().numpy()
        normalized_audio = (audio_data / max(abs(audio_data)) * 32767).astype("int16")

        output_path = f"{tempfile.gettempdir()}/generated_music.wav"
        write(output_path, 44100, normalized_audio)

        return output_path
    except Exception as e:
        return f"Error generating music: {e}"

# ---------------------------------------------------------------------
# Audio Blending Function with Ducking
# ---------------------------------------------------------------------
def blend_audio(voice_path: str, music_path: str, ducking: bool):
    try:
        voice = AudioSegment.from_file(voice_path)
        music = AudioSegment.from_file(music_path)

        if ducking:
            music = music - 10  # Lower music volume for ducking

        combined = music.overlay(voice)
        output_path = f"{tempfile.gettempdir()}/final_promo.wav"
        combined.export(output_path, format="wav")

        return output_path
    except Exception as e:
        return f"Error blending audio: {e}"

# ---------------------------------------------------------------------
# Gradio Interface
# ---------------------------------------------------------------------
with gr.Blocks() as demo:
    gr.Markdown("""
        # 🎧 AI Promo Studio🚀  
        Generate and mix radio promos effortlessly with AI tools!
    """)

    with gr.Tabs():
        with gr.Tab("Step 1: Generate Script"):
            with gr.Row():
                user_prompt = gr.Textbox(label="Promo Idea", placeholder="E.g., A 30-second promo for a morning show.")
                llama_model_id = gr.Textbox(label="Llama Model ID", value="meta-llama/Meta-Llama-3-8B-Instruct")
                duration = gr.Slider(label="Duration (seconds)", minimum=15, maximum=60, step=15, value=30)

            generate_script_button = gr.Button("Generate Script")
            script_output = gr.Textbox(label="Generated Script")
            music_suggestion_output = gr.Textbox(label="Music Suggestion")

            generate_script_button.click(
                fn=lambda user_prompt, model_id, duration: generate_script(user_prompt, model_id, hf_token, duration),
                inputs=[user_prompt, llama_model_id, duration],
                outputs=[script_output, music_suggestion_output],
            )

        with gr.Tab("Step 2: Generate Voice"):
            with gr.Row():
                speaker = gr.Textbox(label="Voice Style (optional)", placeholder="E.g., male, female, or neutral.")

            generate_voice_button = gr.Button("Generate Voice")
            voice_output = gr.Audio(label="Generated Voice", type="filepath")

            generate_voice_button.click(
                fn=lambda script, speaker: generate_voice(script, speaker),
                inputs=[script_output, speaker],
                outputs=[voice_output],
            )

        with gr.Tab("Step 3: Generate Music"):
            with gr.Row():
                audio_length = gr.Slider(label="Music Length (tokens)", minimum=128, maximum=1024, step=64, value=512)

            generate_music_button = gr.Button("Generate Music")
            music_output = gr.Audio(label="Generated Music", type="filepath")

            generate_music_button.click(
                fn=lambda music_suggestion, audio_length: generate_music(music_suggestion, audio_length),
                inputs=[music_suggestion_output, audio_length],
                outputs=[music_output],
            )

        with gr.Tab("Step 4: Blend Audio"):
            with gr.Row():
                ducking = gr.Checkbox(label="Enable Ducking", value=True)

            blend_button = gr.Button("Blend Audio")
            final_output = gr.Audio(label="Final Promo Audio", type="filepath")

            blend_button.click(
                fn=lambda voice_path, music_path, ducking: blend_audio(voice_path, music_path, ducking),
                inputs=[voice_output, music_output, ducking],
                outputs=[final_output],
            )

    gr.Markdown("""
        <hr>
        <p style="text-align: center; font-size: 0.9em;">
            Created with ❤️ by <a href="https://bilsimaging.com" target="_blank">bilsimaging.com</a>
        </p>
    """)

demo.launch(debug=True)