app.py

from huggingface_hub import InferenceClient
from gradio_client import Client
import torch
import nltk  # we'll use this to split into sentences
import numpy as np
from transformers import BarkModel, AutoProcessor
nltk.download('punkt')

import gradio as gr
import os 


def _grab_best_device(use_gpu=True):
    if torch.cuda.device_count() > 0 and use_gpu:
        device = "cuda"
    else:
        device = "cpu"
    return device

device = _grab_best_device()

SYST_PROMPT="""You're the storyteller, crafting a short tale for young listeners. Please abide by these guidelines:
- Keep your sentences short, concise and easy to understand.
- There should be only the narrator speaking. If there are dialogues, they should be indirect."""

#story_prompt = "A panda going on an adventure with a caterpillar. This is a story teaching a wonderful life lesson."
story_prompt = "A princess breaks free from a dragon's grip. This evocates women empowerement and freedom."
temperature = 0.9
top_p = 0.6
repetition_penalty = 1.2

TIMEOUT = int(os.environ.get("TIMEOUT", 45))

temperature = 0.9
top_p = 0.6
repetition_penalty = 1.2




# TODO: requirements: accelerate optimum

text_client = InferenceClient(
    "mistralai/Mistral-7B-Instruct-v0.1",
    timeout=TIMEOUT,
)
image_client = Client("https://openskyml-fast-sdxl-stable-diffusion-xl.hf.space/--replicas/545bst2bq/")
image_negative_prompt = "ultrarealistic, soft lighting, 8k, ugly, text, blurry"
image_positive_prompt = ""
image_seed = 6

processor = AutoProcessor.from_pretrained("suno/bark")

def format_speaker_key(key):
    key = key.replace("v2/", "").split("_")
    
    return f"Speaker {key[2]} ({key[0]})"


voice_presets = [key for key in processor.speaker_embeddings.keys() if "v2/en" in key]
voice_presets_dict = {
    format_speaker_key(key): key for key in voice_presets
}

model = BarkModel.from_pretrained("suno/bark", torch_dtype=torch.float16, use_flash_attention_2=True).to(device)
sampling_rate = model.generation_config.sample_rate
silence = np.zeros(int(0.25 * sampling_rate))  # quarter second of silence
voice_preset = "v2/en_speaker_6"

BATCH_SIZE = 32

# enable CPU offload
model.enable_cpu_offload()

# MISTRAL ONLY 
default_system_understand_message = (
    "I understand, I am a Mistral chatbot."
)
system_understand_message = os.environ.get(
    "SYSTEM_UNDERSTAND_MESSAGE", default_system_understand_message
)

# Mistral formatter
def format_prompt(message):
    prompt = (
        "<s>[INST]" + SYST_PROMPT + "[/INST]" + system_understand_message + "</s>"
    )
    prompt += f"[INST] {message} [/INST]"
    return prompt


def generate_story(
    story_prompt,
    temperature=0.9,
    max_new_tokens=1024,
    top_p=0.95,
    repetition_penalty=1.0,):
    
    temperature = float(temperature)
    if temperature < 1e-2:
        temperature = 1e-2
    top_p = float(top_p)

    generate_kwargs = dict(
        temperature=temperature,
        max_new_tokens=max_new_tokens,
        top_p=top_p,
        repetition_penalty=repetition_penalty,
        do_sample=True,
        seed=42,
    )
    
    try:
        output = text_client.text_generation(
                format_prompt(story_prompt),
                **generate_kwargs,
                details=False,
                return_full_text=False,
            )
    except Exception as e:
        if "Too Many Requests" in str(e):
            print("ERROR: Too many requests on mistral client")
            gr.Warning("Unfortunately Mistral is unable to process")
            output = "Unfortuanately I am not able to process your request now, too many people are asking me !"
        elif "Model not loaded on the server" in str(e):
            print("ERROR: Mistral server down")
            gr.Warning("Unfortunately Mistral LLM is unable to process")
            output = "Unfortuanately I am not able to process your request now, I have problem with Mistral!"
        else:
            print("Unhandled Exception: ", str(e))
            gr.Warning("Unfortunately Mistral is unable to process")
            output = "I do not know what happened but I could not understand you."
        return output

    return output


def generate_audio_and_image(story_prompt, voice_preset="Speaker 3 (en)"):


    story = generate_story(story_prompt)
    
    print(story)
    
    model_input = story.replace("\n", " ").strip()
    model_input = nltk.sent_tokenize(model_input)
    
    print("text generated - now calling for image")
    job_img = image_client.submit(
                    story_prompt+image_positive_prompt,	# str in 'parameter_11' Textbox component
                    image_negative_prompt,	# str in 'parameter_12' Textbox component
                    25,
                    7,
                    1024,
                    1024,
                    image_seed,
                    fn_index=0,
    )
    print("image called - now generating audio")
    
    pieces = []
    for i in range(0, len(model_input), BATCH_SIZE):
        inputs = model_input[i:min(i + BATCH_SIZE, len(model_input))]
        
        if len(inputs) != 0:
            inputs = processor(inputs, voice_preset=voice_presets_dict[voice_preset])
            
            speech_output, output_lengths = model.generate(**inputs.to(device), return_output_lengths=True, min_eos_p=0.2)
            
            speech_output = [output[:length].cpu().numpy() for (output,length) in zip(speech_output, output_lengths)]
            
            print(f"{i}-th part generated")
            pieces += [*speech_output, silence.copy()]
            
    print("Calling image")
    try:
        img = job_img.result()
    except Exception as e:
        print("Unhandled Exception: ", str(e))
        gr.Warning("Unfortunately there was an issue when generating the image with SDXL.")
        img = None
    
    return story, (sampling_rate, np.concatenate(pieces)), img




# Gradio blocks demo    
with gr.Blocks() as demo_blocks:
    gr.Markdown("""<h1 align="center">🐶Children story</h1>""")
    gr.HTML("""<h3 style="text-align:center;">Let Mistral tell you a story</h3>""")
    with gr.Group():
      with gr.Row():
        inp_text = gr.Textbox(label="Story prompt", info="Enter text here")
      with gr.Row():
        with gr.Accordion("Advanced settings", open=False):
            voice_preset = gr.Dropdown(
                    voice_presets_dict,
                    value="Speaker 6 (en)", 
                    label="Available speakers", 
                    )

    
    with gr.Row():
        btn = gr.Button("Create a story")
        
    with gr.Row():    
        with gr.Column(scale=1):
            image_output = gr.Image(elem_id="gallery")
    with gr.Row():
        out_audio = gr.Audio(
                streaming=False, autoplay=True) # needed to stream output audio
        out_text = gr.Text()
        btn.click(generate_audio_and_image, [inp_text, voice_preset], [out_text, out_audio, image_output] ) #[out_audio]) #, out_count])
        
    with gr.Row():
        gr.Examples(
        [
            "A panda going on an adventure with a caterpillar. This is a story teaching a wonderful life lesson.",
            "A princess breaks free from a dragon's grip. This evocates women empowerement and freedom.",
            "Tell me about the wonders of the world.",
            ],
        [inp_text],
        [out_text, out_audio, image_output],
        generate_audio_and_image,
        cache_examples=True,
    ) 
    with gr.Row():
        gr.Markdown(
            """
    This Space uses **[Bark](https://huggingface.co/docs/transformers/main/en/model_doc/bark)**, [Mistral-7b-instruct](https://huggingface.co/mistralai/Mistral-7B-Instruct-v0.1) and [Fast SD-XL](https://huggingface.co/spaces/openskyml/fast-sdxl-stable-diffusion-xl)!
    """
        ) 
demo_blocks.queue().launch(debug=True)