Voice AI

Goal:

The Voice AI project aims to implement a Speech-to-Text system using the Hugging Face Whisper ASR models. 
The primary objectives include accurate transcription of Marathi audio and model fine-tuning for improved performance.

Problem Statement:

Addressing the challenge of accurate Marathi speech transcription is crucial for applications like transcription services, voice assistants, and accessibility tools. 
Inaccurate transcription affects user experience and accessibility for Marathi speakers.

Methodology:

The project utilizes the Hugging Face Whisper ASR models for automatic speech recognition. Fine-tuning strategies.
PEFT (Parameter-Efficient Fine-Tuning) and LORA (Low-Rank Adaptation) technique is explored for efficient training.

Data Collection and Preprocessing:

Common Voice Marathi dataset from Mozilla Foundation is used.
Data preprocessing involves down-sampling audio to 16kHz, feature extraction, and tokenization using the Whisper models' feature extractor and tokenizer.

Model Architecture:

The Whisper ASR models, specifically Whisper Small and Large versions, serve as the primary architecture and used for comparison
PEFT and LORA adaptations are applied to improve training efficiency and adaptation to specific tasks.

Training and Fine-Tuning:

The Seq2SeqTrainingArguments and Seq2SeqTrainer from the Hugging Face Transformers library are utilized for model training.
Fine-tuning strategies are applied to optimize model performance.

Evaluation Metrics:

Word Error Rate (WER) is employed as the primary metric for evaluating model performance. 
The goal is to minimize WER, ensuring accurate transcription of Marathi speech.
Before fine tuning used provided test dataset in whisper large-v3, calculated Average WER is 73.8 and Whisper small Average WER is 93.3

Challenges Faced:

Challenges encountered during the project include GPU memory limitations, fine-tuning difficulties, and handling large models. Strategies to overcome these challenges are discussed.

Storage Constraints: The limited storage capacity in Google Colab posed a challenge, preventing the completion of additional fine-tuning steps due to insufficient space for model checkpoints and intermediate results.
Low GPU Resources: The free version of Google Colab provided inadequate GPU capacity, hindering the fine-tuning of larger and more complex models. This limitation impacted the training efficiency and overall model performance.
Model Complexity vs Steps: Balancing increased model complexity with a lower number of fine-tuning steps presented a challenge. The compromise led to a higher Word Error Rate (WER), indicating the impact of insufficient training steps on the model's language understanding and transcription accuracy.

Results:

Due to storage and GPU limitations, the Voice AI project faced challenges, leading to incomplete fine-tuning, reduced model performance, and trade-offs in model size. These constraints may result in suboptimal transcription accuracy and language understanding	.
This Fine tuning was not working as expected. But I tried my best to perform tuning.

Future Work:

Future enhancements will involve exploring additional pre-trained models, incorporating more diverse datasets, and experimenting with alternative fine-tuning techniques with adequate GPU and Storage.

Credits:

Datasets sourced from Mozilla Common Voice 11.0. Model Tuning: Hugging Face's Whisper-Small (https://huggingface.co/openai/whisper-small)

Project Execution:

Compare Word Error Rate of large and small models with this notebook: [WER Comparison](https://github.com/praveendecode/Voice_AI/blob/main/Source/Base_Model_Word_Error_Rate.ipynb)
Fine-tune using: [Fine-Tuning Process](https://github.com/praveendecode/Voice_AI/blob/main/Source/Fine_Tuning_Whisper_OpenAI_Small.ipynb)
For inference, use: [Voice AI Inference Script](https://github.com/praveendecode/Voice_AI/blob/main/Source/voice_ai.py)

Note: All code explanations has given in the google colab-notebook