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package ma.enset.brain_tumor_segmentation; | |
import org.deeplearning4j.nn.conf.inputs.InputType; | |
import org.deeplearning4j.nn.conf.layers.samediff.SDLayerParams; | |
import org.deeplearning4j.nn.conf.layers.samediff.SameDiffOutputLayer; | |
import org.nd4j.autodiff.samediff.SDVariable; | |
import org.nd4j.autodiff.samediff.SameDiff; | |
import org.nd4j.linalg.api.ndarray.INDArray; | |
import java.util.Map; | |
public class SameDiffTverskyLossLayer extends SameDiffOutputLayer { | |
////Small constant to prevent division by zero. | |
double epsilon=1.0E-8; | |
double alpha=0.7; | |
double beta=1-alpha; | |
@Override | |
public SDVariable defineLayer(SameDiff sameDiff, SDVariable layerInput, SDVariable labels, Map<String, SDVariable> paramTable) { | |
SDVariable numerator = layerInput.mul(labels).sum(1,2,3); | |
SDVariable denominator = layerInput.mul(labels).sum(1,2,3) | |
.add(layerInput.mul(labels.rsub(1.0)).sum(1,2,3)).mul(alpha) | |
.add(layerInput.rsub(1.0).mul(labels).sum(1,2,3)).mul(beta).add(epsilon); | |
SDVariable loss = numerator.div(denominator); | |
return loss.rsub(1.0); | |
} | |
@Override | |
public String activationsVertexName() { | |
return "input"; | |
} | |
@Override | |
public void defineParameters(SDLayerParams params) { | |
//No op for loss layer (no params) | |
} | |
@Override | |
public void initializeParameters(Map<String, INDArray> params) { | |
//No op for loss layer (no params) | |
} | |
@Override | |
public InputType getOutputType(int layerIndex, InputType inputType) { | |
return null; | |
} | |
} |
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