org.deeplearning4j.nn.conf.preprocessor

Class RnnToCnnPreProcessor

java.lang.Object

org.deeplearning4j.nn.conf.preprocessor.RnnToCnnPreProcessor

All Implemented Interfaces:

Serializable, Cloneable, InputPreProcessor

public class RnnToCnnPreProcessor
extends Object
implements InputPreProcessor

A preprocessor to allow RNN and CNN layers to be used together
For example, time series (video) input -> ConvolutionLayer, or conceivable GravesLSTM -> ConvolutionLayer
Functionally equivalent to combining RnnToFeedForwardPreProcessor + FeedForwardToCnnPreProcessor
Specifically, this does two things:
(a) Reshape 3d activations out of RNN layer, with shape [miniBatchSize, numChannels*inputHeight*inputWidth, timeSeriesLength]) into 4d (CNN) activations (with shape [numExamples*timeSeriesLength, numChannels, inputWidth, inputHeight])
(b) Reshapes 4d epsilons (weights.*deltas) out of CNN layer (with shape [numExamples*timeSeriesLength, numChannels, inputHeight, inputWidth]) into 3d epsilons with shape [miniBatchSize, numChannels*inputHeight*inputWidth, timeSeriesLength] suitable to feed into CNN layers. Note: numChannels is equivalent to depth or featureMaps referenced in different literature

Author:

Alex Black

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
RnnToCnnPreProcessor(int inputHeight, int inputWidth, int numChannels)

Method Summary

Modifier and Type	Method and Description
INDArray	backprop(INDArray output, int miniBatchSize, LayerWorkspaceMgr workspaceMgr) Reverse the preProcess during backprop.
RnnToCnnPreProcessor	clone()
Pair<INDArray,MaskState>	feedForwardMaskArray(INDArray maskArray, MaskState currentMaskState, int minibatchSize)
InputType	getOutputType(InputType inputType) For a given type of input to this preprocessor, what is the type of the output?
INDArray	preProcess(INDArray input, int miniBatchSize, LayerWorkspaceMgr workspaceMgr) Pre preProcess input/activations for a multi layer network

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RnnToCnnPreProcessor

public RnnToCnnPreProcessor(int inputHeight,
                            int inputWidth,
                            int numChannels)

Method Detail

preProcess

public INDArray preProcess(INDArray input,
                           int miniBatchSize,
                           LayerWorkspaceMgr workspaceMgr)

Description copied from interface: InputPreProcessor

Pre preProcess input/activations for a multi layer network

Specified by:

preProcess in interface InputPreProcessor

Parameters:

input - the input to pre preProcess

miniBatchSize - Minibatch size

workspaceMgr - Workspace manager

Returns:

the processed input. Note that the returned array should be placed in the ArrayType.ACTIVATIONS workspace via the workspace manager

backprop

public INDArray backprop(INDArray output,
                         int miniBatchSize,
                         LayerWorkspaceMgr workspaceMgr)

Description copied from interface: InputPreProcessor

Reverse the preProcess during backprop. Process Gradient/epsilons before passing them to the layer below.

Specified by:

backprop in interface InputPreProcessor

Parameters:

output - which is a pair of the gradient and epsilon

miniBatchSize - Minibatch size

workspaceMgr - Workspace manager

Returns:

the reverse of the pre preProcess step (if any). Note that the returned array should be placed in ArrayType.ACTIVATION_GRAD workspace via the workspace manager

clone

public RnnToCnnPreProcessor clone()

Specified by:

clone in interface InputPreProcessor

Overrides:

clone in class Object

getOutputType

public InputType getOutputType(InputType inputType)

Description copied from interface: InputPreProcessor

For a given type of input to this preprocessor, what is the type of the output?

Specified by:

getOutputType in interface InputPreProcessor

Parameters:

inputType - Type of input for the preprocessor

Returns:

Type of input after applying the preprocessor

feedForwardMaskArray

public Pair<INDArray,MaskState> feedForwardMaskArray(INDArray maskArray,
                                                     MaskState currentMaskState,
                                                     int minibatchSize)

Specified by:

feedForwardMaskArray in interface InputPreProcessor