
Image Caption Generator
Project Title : Image Caption Generator
Objective:
To build a system that automatically generates relevant captions for images by combining machine learning techniques from both computer vision and natural language processing (NLP).
Tools & Technologies:
Programming Language: Python
Libraries: TensorFlow / Keras, NumPy, Matplotlib, NLTK
Models: CNN (e.g., InceptionV3, VGG16) for image feature extraction,
LSTM for sequence generation
Dataset: Flickr8k, Flickr30k, or MS COCO
How It Works (Machine Learning Approach):
Preprocessing Images:
Use a pre-trained CNN (like InceptionV3) to extract features (bottleneck features) from images.
These features are treated as input vectors representing the image.
Processing Captions:
Clean and tokenize text data.
Convert captions into sequences of integers using a vocabulary dictionary.
Model Architecture:
Image features + Text input are merged and passed into an LSTM network.
The LSTM predicts the next word in the sequence until a full caption is generated.
Training:
Train the model on image-caption pairs using a supervised learning approach.
Use cross-entropy loss and Adam optimizer to adjust weights.
Prediction:
For a new image, extract features → feed to the model → generate caption word-by-word.
Evaluation Metrics:
BLEU Score (Bilingual Evaluation Understudy)
METEOR Score
Human evaluation (optional)
What Students Learn:
Integration of computer vision and NLP
Use of pre-trained models (transfer learning)
Data preprocessing in ML pipelines
Sequence modeling using RNNs/LSTMs
Practical implementation of end-to-end ML systems
Possible Extensions:
Use Transformer-based models (e.g., BERT or ViT + GPT)
Add attention mechanism to improve results
Deploy as a web or mobile app