In this assignment you will implement recurrent networks, and apply them to image captioning on Microsoft COCO. We will also introduce the TinyImageNet dataset, and use a pretrained model on this dataset to explore different applications of image gradients.

The goals of this assignment are as follows:

• understand the architecture of recurrent neural networks (RNNs) and how they operate on sequences by sharing weights over time
• understand the difference between vanilla RNNs and Long-Short Term Memory (LSTM)
• understand how to sample from an RNN at test-time
• understand how to combine convolutional neural nets and recurrent nets to implement an image captioning system
• understand how a trained convolutional network can be used to compute gradients with respect to the input image
• implement and different applications of image gradients, including saliency maps, fooling images, class visualizations, feature inversion, and DeepDream.

Q1: Image Captioning with Vanilla RNNs (Completed)

The IPython notebook RNN_Captioning.ipynb will walk you through the implementation of an image captioning system on MS-COCO using vanilla recurrent networks.

Q2: Image Captioning with LSTMs (Completed)

The IPython notebook LSTM_Captioning.ipynb will walk you through the implementation of Long-Short Term Memory (LSTM) RNNs, and apply them to image captioning on MS-COCO.

Q3: Image Gradients: Saliency maps and Fooling Images (Not Yet)

The IPython notebook ImageGradients.ipynb will introduce the TinyImageNet dataset. You will use a pretrained model on this dataset to compute gradients with respect to the image, and use them to produce saliency maps and fooling images.

Q4: Image Generation: Classes, Inversion, DeepDream (Not Yet)

In the IPython notebook ImageGeneration.ipynb you will use the pretrained TinyImageNet model to generate images. In particular you will generate class visualizations and implement feature inversion and DeepDream.