Documentation

imageInputLayer (Deep Learning Toolbox)

An image input layer inputs 2-D images to a network and applies data normalization.

Code generation does not support 'Normalization' specified using a function handle.

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Yes

sequenceInputLayer (Deep Learning Toolbox)

A sequence input layer inputs sequence data to a network.

The cuDNN library supports vector and 2-D image sequences. The TensorRT library support only vector input sequences.

For vector sequence inputs, the number of features must be a constant during code generation.

For image sequence inputs, the height, width, and the number of channels must be a constant during code generation.

Code generation does not support 'Normalization' specified using a function handle.

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Yes

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convolution2dLayer (Deep Learning Toolbox)

A 2-D convolutional layer applies sliding convolutional filters to the input.

Yes

Yes

Yes

fullyConnectedLayer (Deep Learning Toolbox)

A fully connected layer multiplies the input by a weight matrix and then adds a bias vector.

Yes

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groupedConvolution2dLayer (Deep Learning Toolbox)

A 2-D grouped convolutional layer separates the input channels into groups and applies sliding convolutional filters. Use grouped convolutional layers for channel-wise separable (also known as depth-wise separable) convolution.

Code generation for the ARM Mali GPU is not supported for a 2-D grouped convolution layer that has the NumGroups property set as 'channel-wise' or a value greater than two.

Yes

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Yes

transposedConv2dLayer (Deep Learning Toolbox)

A transposed 2-D convolution layer upsamples feature maps.

Yes

Yes

Yes

bilstmLayer (Deep Learning Toolbox)

A bidirectional LSTM (BiLSTM) layer learns bidirectional long-term dependencies between time steps of time series or sequence data. These dependencies can be useful when you want the network to learn from the complete time series at each time step.

For code generation, the StateActivationFunction property must be set to 'tanh'.

For code generation, the GateActivationFunction property must be set to 'sigmoid'.

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flattenLayer (Deep Learning Toolbox)

A flatten layer collapses the spatial dimensions of the input into the channel dimension.

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No

gruLayer (Deep Learning Toolbox)

A GRU layer learns dependencies between time steps in time series and sequence data.

Code generation supports only the 'after-multiplication' and 'recurrent-bias-after-multiplication' reset gate modes.

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Yes

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lstmLayer (Deep Learning Toolbox)

An LSTM layer learns long-term dependencies between time steps in time series and sequence data.

For code generation, the StateActivationFunction property must be set to 'tanh'.

For code generation, the GateActivationFunction property must be set to 'sigmoid'.

Yes

Yes

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sequenceFoldingLayer (Deep Learning Toolbox)

A sequence folding layer converts a batch of image sequences to a batch of images. Use a sequence folding layer to perform convolution operations on time steps of image sequences independently.

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No

sequenceInputLayer (Deep Learning Toolbox)

A sequence input layer inputs sequence data to a network.

The cuDNN library supports vector and 2-D image sequences. The TensorRT library support only vector input sequences.

For vector sequence inputs, the number of features must be a constant during code generation.

For image sequence inputs, the height, width, and the number of channels must be a constant during code generation.

Code generation does not support 'Normalization' specified using a function handle.

Yes

Yes

No

sequenceUnfoldingLayer (Deep Learning Toolbox)

A sequence unfolding layer restores the sequence structure of the input data after sequence folding.

Yes

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No

wordEmbeddingLayer (Text Analytics Toolbox)

A word embedding layer maps word indices to vectors.

Yes

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clippedReluLayer (Deep Learning Toolbox)

A clipped ReLU layer performs a threshold operation, where any input value less than zero is set to zero and any value above the clipping ceiling is set to that clipping ceiling.

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Yes

eluLayer (Deep Learning Toolbox)

An ELU activation layer performs the identity operation on positive inputs and an exponential nonlinearity on negative inputs.

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leakyReluLayer (Deep Learning Toolbox)

A leaky ReLU layer performs a threshold operation, where any input value less than zero is multiplied by a fixed scalar.

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Yes

reluLayer (Deep Learning Toolbox)

A ReLU layer performs a threshold operation to each element of the input, where any value less than zero is set to zero.

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Yes

softplusLayer (Reinforcement Learning Toolbox)

A SoftplusLayer is a deep neural network layer that implements the softplus activation Y = log(1 + e^X), which ensures that the output is always positive

Yes

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tanhLayer (Deep Learning Toolbox)

A hyperbolic tangent (tanh) activation layer applies the tanh function on the layer inputs.

Yes

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Yes

batchNormalizationLayer (Deep Learning Toolbox)

A batch normalization layer normalizes each input channel across a mini-batch.

Yes

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Yes

crop2dLayer (Deep Learning Toolbox)

A 2-D crop layer applies 2-D cropping to the input.

Yes

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crossChannelNormalizationLayer (Deep Learning Toolbox)

A channel-wise local response (cross-channel) normalization layer carries out channel-wise normalization.

Yes

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Yes

dropoutLayer (Deep Learning Toolbox)

A dropout layer randomly sets input elements to zero with a given probability.

Yes

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Yes

scalingLayer (Reinforcement Learning Toolbox)

Scaling layer for actor or critic network.

For code generation, values for the 'Scale' and 'Bias' properties must have the same dimension.

Yes

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Yes

averagePooling2dLayer (Deep Learning Toolbox)

An average pooling layer performs down-sampling by dividing the input into rectangular pooling regions and computing the average values of each region.

Yes

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Yes

globalAveragePooling2dLayer (Deep Learning Toolbox)

A global average pooling layer performs down-sampling by computing the mean of the height and width dimensions of the input.

Yes

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Yes

globalMaxPooling2dLayer (Deep Learning Toolbox)

A global max pooling layer performs down-sampling by computing the maximum of the height and width dimensions of the input.

Yes

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Yes

maxPooling2dLayer (Deep Learning Toolbox)

A max pooling layer performs down-sampling by dividing the input into rectangular pooling regions, and computing the maximum of each region.

Yes

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Yes

maxUnpooling2dLayer (Deep Learning Toolbox)

A max unpooling layer unpools the output of a max pooling layer.

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additionLayer (Deep Learning Toolbox)

An addition layer adds inputs from multiple neural network layers element-wise.

Yes

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Yes

concatenationLayer (Deep Learning Toolbox)

A concatenation layer takes inputs and concatenates them along a specified dimension.

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depthConcatenationLayer (Deep Learning Toolbox)

A depth concatenation layer takes inputs that have the same height and width and concatenates them along the third dimension (the channel dimension).

Yes

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Yes

anchorBoxLayer (Computer Vision Toolbox)

An anchor box layer stores anchor boxes for a feature map used in object detection networks.

Yes

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focalLossLayer (Computer Vision Toolbox)

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spaceToDepthLayer (Computer Vision Toolbox)

Yes

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Yes

ssdMergeLayer (Computer Vision Toolbox)

An SSD merge layer merges the outputs of feature maps for subsequent regression and classification loss computation.

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rcnnBoxRegressionLayer (Computer Vision Toolbox)

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rpnClassificationLayer (Computer Vision Toolbox)

Yes

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Yes

YOLOv2OutputLayer (Computer Vision Toolbox)

Create output layer for YOLO v2 object detection network.

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Yes

YOLOv2ReorgLayer (Computer Vision Toolbox)

Create reorganization layer for YOLO v2 object detection network.

Yes

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Yes

YOLOv2TransformLayer (Computer Vision Toolbox)

Create transform layer for YOLO v2 object detection network.

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Yes

classificationLayer (Deep Learning Toolbox)

A classification layer computes the cross entropy loss for multi-class classification problems with mutually exclusive classes.

Yes

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Yes

dicePixelClassificationLayer (Computer Vision Toolbox)

A Dice pixel classification layer provides a categorical label for each image pixel or voxel using generalized Dice loss.

Yes

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Yes

focalLossLayer (Computer Vision Toolbox)

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Yes

Output Layer (Deep Learning Toolbox)

All output layers including custom classification or regression output layers created by using nnet.layer.ClassificationLayer or nnet.layer.RegressionLayer.

For an example showing how to define a custom classification output layer and specify a loss function, see Define Custom Classification Output Layer (Deep Learning Toolbox).

For an example showing how to define a custom regression output layer and specify a loss function, see Define Custom Regression Output Layer (Deep Learning Toolbox).

Yes

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Yes

pixelClassificationLayer (Computer Vision Toolbox)

A pixel classification layer provides a categorical label for each image pixel or voxel.

Yes

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Yes

rcnnBoxRegressionLayer (Computer Vision Toolbox)

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Yes

regressionLayer (Deep Learning Toolbox)

A regression layer computes the half-mean-squared-error loss for regression problems.

Yes

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Yes

rpnClassificationLayer (Computer Vision Toolbox)

Yes

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Yes

sigmoidLayer (Deep Learning Toolbox)

A sigmoid layer applies a sigmoid function to the input.

Yes

Yes

Yes

softmaxLayer (Deep Learning Toolbox)

A softmax layer applies a softmax function to the input.

Yes

Yes

Yes

nnet.keras.layer.FlattenCStyleLayer (Deep Learning Toolbox)

Flatten activations into 1-D assuming C-style (row-major) order.

Yes

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Yes

nnet.keras.layer.GlobalAveragePooling2dLayer (Deep Learning Toolbox)

Global average pooling layer for spatial data.

Yes

Yes

Yes

nnet.keras.layer.SigmoidLayer (Deep Learning Toolbox)

Sigmoid activation layer.

Yes

Yes

Yes

nnet.keras.layer.TanhLayer (Deep Learning Toolbox)

Hyperbolic tangent activation layer.

Yes

Yes

Yes

nnet.keras.layer.ZeroPadding2dLayer (Deep Learning Toolbox)

Zero padding layer for 2-D input.

Yes

Yes

Yes

nnet.onnx.layer.ElementwiseAffineLayer (Deep Learning Toolbox)

Layer that performs element-wise scaling of the input followed by an addition.

Yes

Yes

Yes

nnet.onnx.layer.FlattenLayer (Deep Learning Toolbox)

Flattens the spatial dimensions of the input tensor to the channel dimensions.

Yes

Yes

Yes

nnet.onnx.layer.IdentityLayer (Deep Learning Toolbox)

Layer that implements ONNX identity operator.

Yes

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Yes

Custom layers

Custom layers, with or without learnable parameters, that you define for your problem.

To learn how to define custom deep learning layers, see Define Custom Deep Learning Layers (Deep Learning Toolbox) and Define Custom Deep Learning Layer for Code Generation (Deep Learning Toolbox).

For an example on how to generate code for a network with custom layers, see Code Generation For Object Detection Using YOLO v3 Deep Learning.

The outputs of the custom layer must be fixed-size arrays.

Using 'unified' as the MallocMode in coder.gpuConfig requires extra memory copies leading to slower performance. For custom layers, it is recommended to use 'discrete' mode. For more information on GPU memory allocation, see Discrete and Managed Modes

cuDNN targets support both row-major and column-major code generation for custom layers. TensorRT targets support only column-major code generation.

Code generation for a sequence network containing custom layer and LSTM or GRU layer is not supported.

Code generation for a deep learning network with custom layer is not supported in Simulink^®.

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