app.py

import io
import torch
from transformers import WhisperProcessor, WhisperForConditionalGeneration
import requests
from bs4 import BeautifulSoup
import tempfile    
import os
from pydub import AudioSegment
import dash
from dash import dcc, html, Input, Output, State
import dash_bootstrap_components as dbc
from dash.exceptions import PreventUpdate
import threading
from pytube import YouTube

print("Script started")

# Check if CUDA is available and set the device
device = "cuda" if torch.cuda.is_available() else "cpu"
print(f"Using device: {device}")

# Load the Whisper model and processor
model_name = "openai/whisper-small"
processor = WhisperProcessor.from_pretrained(model_name)
model = WhisperForConditionalGeneration.from_pretrained(model_name).to(device)

def download_audio_from_url(url):
    try:
        if "youtube.com" in url or "youtu.be" in url:
            print("Processing YouTube URL...")
            yt = YouTube(url)
            audio_stream = yt.streams.filter(only_audio=True).first()
            with tempfile.NamedTemporaryFile(delete=False, suffix=".mp4") as temp_file:
                audio_stream.download(output_path=temp_file.name)
                audio_bytes = open(temp_file.name, "rb").read()
            os.unlink(temp_file.name)
        elif "share" in url:
            print("Processing shareable link...")
            response = requests.get(url)
            soup = BeautifulSoup(response.content, 'html.parser')
            video_tag = soup.find('video')
            if video_tag and 'src' in video_tag.attrs:
                video_url = video_tag['src']
                print(f"Extracted video URL: {video_url}")
            else:
                raise ValueError("Direct video URL not found in the shareable link.")
            response = requests.get(video_url)
            audio_bytes = response.content
        else:
            print(f"Downloading video from URL: {url}")
            response = requests.get(url)
            audio_bytes = response.content
        
        print(f"Successfully downloaded {len(audio_bytes)} bytes of data")
        return audio_bytes
    except Exception as e:
        print(f"Error in download_audio_from_url: {str(e)}")
        raise

def transcribe_audio(audio_file):
    try:
        print("Loading audio file...")
        audio = AudioSegment.from_file(audio_file)
        audio = audio.set_channels(1).set_frame_rate(16000)
        audio_array = audio.get_array_of_samples()
        
        print("Starting transcription...")
        input_features = processor(audio_array, sampling_rate=16000, return_tensors="pt").input_features.to(device)
        predicted_ids = model.generate(input_features)
        transcription = processor.batch_decode(predicted_ids, skip_special_tokens=True)
        
        print(f"Transcription complete. Length: {len(transcription[0])} characters")
        return transcription[0]
    except Exception as e:
        print(f"Error in transcribe_audio: {str(e)}")
        raise

def transcribe_video(url):
    try:
        print(f"Attempting to download audio from URL: {url}")
        audio_bytes = download_audio_from_url(url)
        print(f"Successfully downloaded {len(audio_bytes)} bytes of audio data")
        
        with tempfile.NamedTemporaryFile(delete=False, suffix=".wav") as temp_audio:
            AudioSegment.from_file(io.BytesIO(audio_bytes)).export(temp_audio.name, format="wav")
            transcript = transcribe_audio(temp_audio.name)
        
        os.unlink(temp_audio.name)
        return transcript
    except Exception as e:
        error_message = f"An error occurred: {str(e)}"
        print(error_message)
        return error_message

app = dash.Dash(__name__, external_stylesheets=[dbc.themes.BOOTSTRAP])

app.layout = dbc.Container([
    dbc.Row([
        dbc.Col([
            html.H1("Video Transcription", className="text-center mb-4"),
            dbc.Card([
                dbc.CardBody([
                    dbc.Input(id="video-url", type="text", placeholder="Enter video URL"),
                    dbc.Button("Transcribe", id="transcribe-button", color="primary", className="mt-3"),
                    dbc.Spinner(html.Div(id="transcription-output", className="mt-3")),
                    dcc.Download(id="download-transcript")
                ])
            ])
        ], width=12)
    ])
], fluid=True)

@app.callback(
    Output("transcription-output", "children"),
    Output("download-transcript", "data"),
    Input("transcribe-button", "n_clicks"),
    State("video-url", "value"),
    prevent_initial_call=True
)
def update_transcription(n_clicks, url):
    if not url:
        raise PreventUpdate

    def transcribe():
        try:
            transcript = transcribe_video(url)
            return transcript
        except Exception as e:
            return f"An error occurred: {str(e)}"

    # Run transcription in a separate thread
    thread = threading.Thread(target=transcribe)
    thread.start()
    thread.join()

    transcript = thread.result if hasattr(thread, 'result') else "Transcription failed"

    if transcript and not transcript.startswith("An error occurred"):
        download_data = dict(content=transcript, filename="transcript.txt")
        return dbc.Card([
            dbc.CardBody([
                html.H5("Transcription Result"),
                html.Pre(transcript, style={"white-space": "pre-wrap", "word-wrap": "break-word"}),
                dbc.Button("Download Transcript", id="btn-download", color="secondary", className="mt-3")
            ])
        ]), download_data
    else:
        return transcript, None

print("Reached end of script definitions")

if __name__ == '__main__':
    print("Starting the Dash application...")
    app.run(debug=True, host='0.0.0.0', port=7860)
    print("Dash application has finished running.")