createAlexNetModel2D: 2-D implementation of the AlexNet deep learning architecture.

In ANTsX/ANTsRNet: Neural Networks for Medical Image Processing

2-D implementation of the AlexNet deep learning architecture.

Description

Creates a keras model of the AlexNet deep learning architecture for image recognition based on the paper

Usage

createAlexNetModel2D(
  inputImageSize,
  numberOfOutputs = 1000,
  numberOfDenseUnits = 4096,
  dropoutRate = 0,
  mode = c("classification", "regression"),
  batch_size = NULL
)

Arguments

inputImageSize	Used for specifying the input tensor shape. The shape (or dimension) of that tensor is the image dimensions followed by the number of channels (e.g., red, green, and blue). The batch size (i.e., number of training images) is not specified a priori.
numberOfOutputs	Number of segmentation labels.
numberOfDenseUnits	number of dense units.
dropoutRate	optional regularization parameter between ⁠[0, 1]⁠. Default = 0.0.
mode	'classification' or 'regression'.
batch_size	batch size to pass to first layer

Details

A. Krizhevsky, and I. Sutskever, and G. Hinton. ImageNet Classification with Deep Convolutional Neural Networks.

available here:

    http://papers.nips.cc/paper/4824-imagenet-classification-with-deep-convolutional-neural-networks.pdf

This particular implementation was influenced by the following python implementation:

    https://github.com/duggalrahul/AlexNet-Experiments-Keras/
    https://github.com/lunardog/convnets-keras/

Value

an AlexNet keras model

Author(s)

Tustison NJ

Examples

library( ANTsRNet )
library( keras )


mnistData <- dataset_mnist()
numberOfLabels <- 10

# Extract a small subset for something that can run quickly

X_trainSmall <- mnistData$train$x[1:10,,]
X_trainSmall <- array( data = X_trainSmall, dim = c( dim( X_trainSmall ), 1 ) )
Y_trainSmall <- to_categorical( mnistData$train$y[1:10], numberOfLabels )

X_testSmall <- mnistData$test$x[1:10,,]
X_testSmall <- array( data = X_testSmall, dim = c( dim( X_testSmall ), 1 ) )
Y_testSmall <- to_categorical( mnistData$test$y[1:10], numberOfLabels )

# We add a dimension of 1 to specify the channel size

inputImageSize <- c( dim( X_trainSmall )[2:3], 1 )

model <- createAlexNetModel2D( inputImageSize = inputImageSize,
  numberOfOutputs = numberOfLabels )

model %>% compile( loss = 'categorical_crossentropy',
  optimizer = optimizer_adam( lr = 0.0001 ),
  metrics = c( 'categorical_crossentropy', 'accuracy' ) )
gc()
rm(mnistData); gc()
# Comment out the rest due to travis build constraints

# track <- model %>% fit( X_trainSmall, Y_trainSmall, verbose = 1,
#   epochs = 1, batch_size = 2, shuffle = TRUE, validation_split = 0.5 )

# Now test the model

# testingMetrics <- model %>% evaluate( X_testSmall, Y_testSmall )
# predictedData <- model %>% predict( X_testSmall, verbose = 1 )
rm(model); gc()

ANTsX/ANTsRNet documentation built on Nov. 21, 2024, 4:07 a.m.