MPSCNNLossDescriptor(3) MetalPerformanceShaders.framework MPSCNNLossDescriptor(3)
NAME
MPSCNNLossDescriptor
SYNOPSIS
#import <MPSCNNLoss.h>
Inherits NSObject, and <NSCopying>.
Instance Methods
(nonnull instancetype) - init
Class Methods
(nullable MPSCNNLossDescriptor *) + cnnLossDescriptorWithType:reductionType:
Properties
MPSCNNLossType lossType
MPSCNNReductionType reductionType
float weight
float labelSmoothing
NSUInteger numberOfClasses
float epsilon
float delta
Detailed Description
This depends on Metal.framework. The MPSCNNLossDescriptor specifies a loss filter descriptor. The same descriptor can be used to
initialize both the MPSCNNLoss and the MPSCNNLossGradient filters.
Method Documentation
+ (nullable MPSCNNLossDescriptor*) cnnLossDescriptorWithType: (MPSCNNLossType) lossType(MPSCNNReductionType) reductionType
Make a descriptor for a MPSCNNLoss or MPSCNNLossGradient object.
Parameters:
lossType The type of a loss filter.
reductionType The type of a reduction operation to apply. This argument is ignored in the MPSCNNLossGradient filter.
Returns:
A valid MPSCNNLossDescriptor object or nil, if failure.
- (nonnull instancetype) init
Property Documentation
- delta [read], [write], [nonatomic], [assign]
The delta parameter. The default value is 1.0f. This parameter is valid only for the loss functions of the following type(s):
MPSCNNLossTypeHuber.
Given predictions and labels (ground truth), it is applied in the following way: if (|predictions - labels| <= delta, loss = 0.5f *
predictions^2 if (|predictions - labels| > delta, loss = 0.5 * delta^2 + delta * (|predictions - labels| - delta)
- epsilon [read], [write], [nonatomic], [assign]
The epsilon parameter. The default value is 1e-7. This parameter is valid only for the loss functions of the following type(s):
MPSCNNLossTypeLog.
Given predictions and labels (ground truth), it is applied in the following way: -(labels * log(predictions + epsilon)) - ((1 - labels) *
log(1 - predictions + epsilon))
- labelSmoothing [read], [write], [nonatomic], [assign]
The label smoothing parameter. The default value is 0.0f. This parameter is valid only for the loss functions of the following type(s):
MPSCNNLossFunctionTypeSoftmaxCrossEntropy, MPSCNNLossFunctionTypeSigmoidCrossEntropy.
MPSCNNLossFunctionTypeSoftmaxCrossEntropy: given labels (ground truth), it is applied in the following way: labels = labelSmoothing > 0 ?
labels * (1 - labelSmoothing) + labelSmoothing / numberOfClasses : labels
MPSCNNLossFunctionTypeSigmoidCrossEntropy: given labels (ground truth), it is applied in the following way: labels = labelSmoothing > 0 ?
labels * (1 - labelSmoothing) + 0.5 * labelSmoothing : labels
- lossType [read], [write], [nonatomic], [assign]
The type of a loss filter. This parameter specifies the type of a loss filter.
- numberOfClasses [read], [write], [nonatomic], [assign]
The number of classes parameter. The default value is 1. This parameter is valid only for the loss functions of the following type(s):
MPSCNNLossFunctionTypeSoftmaxCrossEntropy.
Given labels (ground truth), it is applied in the following way: labels = labelSmoothing > 0 ? labels * (1 - labelSmoothing) +
labelSmoothing / numberOfClasses : labels
- reductionType [read], [write], [nonatomic], [assign]
The type of a reduction operation performed in the loss filter. This parameter specifies the type of a reduction operation performed in
the loss filter.
- weight [read], [write], [nonatomic], [assign]
The scale factor to apply to each element of a result. Each element of a result is multiplied by the weight value. The default value is
1.0f.
Author
Generated automatically by Doxygen for MetalPerformanceShaders.framework from the source code.
Version MetalPerformanceShaders-100 Thu Feb 8 2018 MPSCNNLossDescriptor(3)