Tuesday, July 17, 2018

How to write Dense block of DenseNets: understanding and coding with Keras

Abstract

This article covers basic understanding and coding of Dense block of DenseNets. DenseNets is one of the convolutional neural network models. If you have an experience of using fine-tuning or frequently tackle with image recognition tasks, probably you have heard that before.
DenseNets is composed of Dense blocks. It is expressed as the image below, which is quoted from https://arxiv.org/abs/1608.06993.



On the context of the history of convolutional neural network, ResNet helps the network to be deeper without degradation problem by the shortcut path to the output of the Residual module. DenseNets and Dense block is near concept from the different approach.

This article is to help to understand the basic concept of Dense block of DenseNets and how to write that. For coding, I’ll use Python and Keras.
About the ResNet and Residual module, please read the article below.
If you want to know the detail of DenseNets and Dense block, I recommend you read the article below.
When you find a mistake, please let me know by comment or mail.

Monday, July 9, 2018

How to write Residual module: understanding and coding with Keras

Abstract

This article covers basic understanding and coding of Residual module. If you have experience of using fine tuning or frequently tackle with image recognition tasks, probably you have heard the network name, ResNet. ResNet is composed of Residual module, whose structure is expressed as below.


The image above is from https://arxiv.org/abs/1512.03385.
Basically, deeper neural network contributes to the better outcome. If you have enough computational resource(unfortunately, I don't have), for difficult task, you can approach it with really deep neural network. However, with deeper neural network, the problem of degradation comes, which makes it difficult to train the model. Residual module offers one of the solutions to this problem, meaning that with this, we can make deeper neural network by softening the difficulty of training.
For precise and better understanding, I recommend that you read the paper below. Here, I'll just show summary for simple and concise understanding and coding with Keras.
If there are strange or wrong points, please let me know by comment or message.