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BNNSFilterCreateLayerResize(_:_:)

Returns a new resize layer.

Declaration

func BNNSFilterCreateLayerResize(_ layer_params: UnsafePointer<BNNSLayerParametersResize>, _ filter_params: UnsafePointer<BNNSFilterParameters>?) -> BNNSFilter?

Parameters

  • layer_params:

    Layer parameters.

  • filter_params:

    The filter runtime parameters.

Discussion

Use a resize layer to copy data between two differently sized tensors using a specified interpolation method. Resized dimensions must all either upsample or downsample; the resize layer doesn’t support combining both directions in a single operation.

For example, to resize the following source data to the specified destination dimensions:

let sourceData: [Float] = [0, 1, 0,
                           1, 1, 1,
                           0, 1, 0]

let destinationWidth = 24
let destinationHeight = 9

var destinationData = [Float](repeating: 0,
                              count: destinationWidth * destinationHeight)

Use the following code:



let inputDescriptor = BNNSNDArrayDescriptor(flags: flags,
                                           layout: BNNSDataLayoutRowMajorMatrix,
                                           size: (3, 3, 0, 0, 0, 0, 0, 0),
                                           stride: (0, 0, 0, 0, 0, 0, 0, 0),
                                           data: nil,
                                           data_type: .float,
                                           table_data: nil,
                                           table_data_type: .float,
                                           data_scale: 1,
                                           data_bias: 0)

let outputDescriptor = BNNSNDArrayDescriptor(flags: flags,
                                            layout: BNNSDataLayoutRowMajorMatrix,
                                            size: (destinationWidth, destinationHeight, 0, 0, 0, 0, 0, 0),
                                            stride: (0, 0, 0, 0, 0, 0, 0, 0),
                                            data: nil,
                                            data_type: .float,
                                            table_data: nil,
                                            table_data_type: .float,
                                            data_scale: 1,
                                            data_bias: 0)

var params = BNNSLayerParametersResize(method: BNNSInterpolationMethodNearest,
                                       i_desc: inputDescriptor,
                                       o_desc: outputDescriptor,
                                       align_corners: false)

let filter = BNNSFilterCreateLayerResize(&params, nil)

defer {
    BNNSFilterDestroy(filter)
}

BNNSFilterApply(filter,
                sourceData,
                &destinationData)

On return, destinationData contains the following values:

0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0

See Also

Resize layers