тензор потока js: как расширить tf.layers.conv2d при написании тензор потока js пользовательских слоев - PullRequest
1 голос
/ 07 марта 2020

Мне нужно написать собственный слой тензорного потока js, чтобы импортировать мою модель. В исходном коде python это реализовано расширениями Conv2D, но, похоже, это невозможно в коде tf js. Обратитесь за помощью.

Сообщение об ошибке İmage

Я новичок в tenorflow и хотел бы узнать, как преобразовать этот пользовательский слой в код tf js, это беспокоило меня долгое время, любая помощь будет принята с благодарностью.

Вот код python Cunstom Layer.


from keras.utils import conv_utils
from keras import backend as K
from keras.engine import InputSpec
from keras.layers import Conv2D


class PConv2D(Conv2D):
    def __init__(self, *args, n_channels=3, mono=False, **kwargs):
        super().__init__(*args, **kwargs)
        self.input_spec = [InputSpec(ndim=4), InputSpec(ndim=4)]

    def build(self, input_shape):        
        """Adapted from original _Conv() layer of Keras        
        param input_shape: list of dimensions for [img, mask]
        """

        if self.data_format == 'channels_first':
            channel_axis = 1
        else:
            channel_axis = -1

        if input_shape[0][channel_axis] is None:
            raise ValueError('The channel dimension of the inputs should be defined. Found `None`.')

        self.input_dim = input_shape[0][channel_axis]

        # Image kernel
        kernel_shape = self.kernel_size + (self.input_dim, self.filters)
        self.kernel = self.add_weight(shape=kernel_shape,
                                      initializer=self.kernel_initializer,
                                      name='img_kernel',
                                      regularizer=self.kernel_regularizer,
                                      constraint=self.kernel_constraint)
        # Mask kernel
        self.kernel_mask = K.ones(shape=self.kernel_size + (self.input_dim, self.filters))

        if self.use_bias:
            self.bias = self.add_weight(shape=(self.filters,),
                                        initializer=self.bias_initializer,
                                        name='bias',
                                        regularizer=self.bias_regularizer,
                                        constraint=self.bias_constraint)
        else:
            self.bias = None
        self.built = True

    def call(self, inputs, mask=None):
        '''
        We will be using the Keras conv2d method, and essentially we have
        to do here is multiply the mask with the input X, before we apply the
        convolutions. For the mask itself, we apply convolutions with all weights
        set to 1.
        Subsequently, we set all mask values >0 to 1, and otherwise 0
        ''' 

        # Both image and mask must be supplied
        if type(inputs) is not list or len(inputs) != 2:
            raise Exception('PartialConvolution2D must be called on a list of two tensors [img, mask]. Instead got: ' + str(inputs))

        # Create normalization. Slight change here compared to paper, using mean mask value instead of sum
        normalization = K.mean(inputs[1], axis=[1,2], keepdims=True)
        normalization = K.repeat_elements(normalization, inputs[1].shape[1], axis=1)
        normalization = K.repeat_elements(normalization, inputs[1].shape[2], axis=2)

        # Apply convolutions to image
        img_output = K.conv2d(
            (inputs[0]*inputs[1]) / normalization, self.kernel, 
            strides=self.strides,
            padding=self.padding,
            data_format=self.data_format,
            dilation_rate=self.dilation_rate
        )

        # Apply convolutions to mask
        mask_output = K.conv2d(
            inputs[1], self.kernel_mask, 
            strides=self.strides,
            padding=self.padding,            
            data_format=self.data_format,
            dilation_rate=self.dilation_rate
        )

        # Where something happened, set 1, otherwise 0        
        mask_output = K.cast(K.greater(mask_output, 0), 'float32')

        # Apply bias only to the image (if chosen to do so)
        if self.use_bias:
            img_output = K.bias_add(
                img_output,
                self.bias,
                data_format=self.data_format)

        # Apply activations on the image
        if self.activation is not None:
            img_output = self.activation(img_output)

        return [img_output, mask_output]

    def compute_output_shape(self, input_shape):
        if self.data_format == 'channels_last':
            space = input_shape[0][1:-1]
            new_space = []
            for i in range(len(space)):
                new_dim = conv_utils.conv_output_length(
                    space[i],
                    self.kernel_size[i],
                    padding=self.padding,
                    stride=self.strides[i],
                    dilation=self.dilation_rate[i])
                new_space.append(new_dim)
            new_shape = (input_shape[0][0],) + tuple(new_space) + (self.filters,)
            return [new_shape, new_shape]
        if self.data_format == 'channels_first':
            space = input_shape[2:]
            new_space = []
            for i in range(len(space)):
                new_dim = conv_utils.conv_output_length(
                    space[i],
                    self.kernel_size[i],
                    padding=self.padding,
                    stride=self.strides[i],
                    dilation=self.dilation_rate[i])
                new_space.append(new_dim)
            new_shape = (input_shape[0], self.filters) + tuple(new_space)
            return [new_shape, new_shape]

Вот мой тф js код

import * as tf from '@tensorflow/tfjs';
import {convOutputLength, deconvLength, normalizeArray} from '@tensorflow/tfjs-layers/dist/utils/conv_utils';
import { InputSpec } from '@tensorflow/tfjs-layers/dist/engine/topology';


class PConv2D extends tf.layers.Layer {
  constructor(config) {
    super({config});
    // TODO(bileschi): Can we point to documentation on masking here?
    this.supportsMasking = true;
    this.inputSpec = [new InputSpec({ ndim: 4 }),new InputSpec({ ndim: 4 })];
    console.log(this.activation)
    if (config != undefined)
    {
        console.log(config.filters);
        this.kernelSize = config.kernelSize;
        this.filters = config.filters;
        this.strides = config.strides;
        this.padding = config.padding;
        this.dataFormat = config.dataFormat;
        this.dilationRate = config.dilationRate;
        this.useBias = config.useBias;
        this.biasInitializer = config.biasInitializer;
        this.biasConstraint = config.biasConstraint;
        this.kernelInitializer = config.kernelInitializer;
        this.kernelRegularizer = config.kernelRegularizer;
        this.activation = config.activation;

    }
    console.log(config);
    //console.log(config.name);
    console.log(this.input_spec);
  }
  build(inputShape) {

    const channelAxis =
        this.dataFormat === 'channelsFirst' ? 1 : inputShape.length - 1;
    if (inputShape[channelAxis] == null) {
      throw new ValueError(
          'The channel dimension of the inputs should be defined. ' +
          'Found `None`.');
    }

    const inputDim = inputShape[0][channelAxis];
    const kernelShape = this.kernelSize.concat([inputDim,this.filters]);

    // Image kernel

    this.kernel = this.addWeight(
        'img_kernel', kernelShape, 'float32', this.kernelInitializer,
        this.kernelRegularizer, true, this.kernelConstraint);

    this.kernel_mask = tf.ones(kernelShape);

    if (this.useBias) {
      this.bias = this.addWeight(
          'bias', [this.filters], 'float32', this.biasInitializer,
          this.biasRegularizer, true, this.biasConstraint);
      };

    this.built = true;
    this.inputSpec = [new InputSpec({ ndim: 4 }),new InputSpec({ ndim: 4 })];
    //this.inputSpec = [{ndim: 4},{ndim: 4}];


    };

  computeOutputShape(inputShape) {
    const space = (this.dataFormat === 'channelsLast') ?
      inputShape[0].slice(1, inputShape.length - 1) :
      inputShape.slice(2);

    const newSpace = [];

    for (let i = 0; i < space.length; ++i) {
        const newDim = convOutputLength(
            space[i], this.kernelSize[i], this.padding, this.strides[i],
            typeof this.dilationRate === 'number' ? this.dilationRate :
                                                    this.dilationRate[i]);
        newSpace.push(newDim);
    }
    let outputShape = [inputShape[0]];

  if (this.dataFormat === 'channelsLast') {
        outputShape = outputShape[0].concat(newSpace);
        outputShape.push(this.filters);
      } else {
        outputShape.push(this.filters);
        outputShape = outputShape.concat(newSpace);
      }

    return [outputShape,outputShape];

  }

  call(inputs, kwargs) {


    return tf.tidy(() => {
      // if (inputs.length !== 2) {
      //     throw new ValueError(
      //         'PartialConvolution2D must be called on a list of two tensors [img, mask]');
      // }

      let normalization = tf.mean(inputs[1], [1,2],true)
      normalization = normalization.tile([1, inputs[0].shape[1], inputs[0].shape[2],1])


      let a = tf.mul(inputs[0],inputs[1])
      a = tf.mul(a,normalization)

      let img_outputs = tf.conv2d(
          a,this.filters, this.kernel.read(),
          this.strides, this.padding, this.dataFormat,this.dilationRate);

      let mask_outputs = tf.conv2d(
          inputs[1],this.filters, this.kernel.read(),
          this.strides, this.padding, this.dataFormat,this.dilationRate);

      mask_outputs = K.cast(K.greater(mask_output, 0), 'float32')

      if (this.activation != null) {
        img_outputs = this.activation.apply(img_outputs);
      }
      return [img_outputs, mask_outputs];

    });


  }

  /**
   * If a custom layer class is to support serialization, it must implement
   * the `className` static getter.
   */
  static get className() {
    return 'PConv2D';
  }
  getConfig() {
    const config = super.getConfig();
    //Object.assign(config, {kernelSize: this.kernelSize});
    console.log(config)
    return config;
  }
}
tf.serialization.registerClass(PConv2D);  // Needed for serialization.

export function pconv2d() {
  return new PConv2D();
}

var myTester = new pconv2d()

1 Ответ

0 голосов
/ 09 апреля 2020

Ошибка вызвана

var myTester = new pconv2d ()

pconv2d нуждается в kernelSize и фильтрах. Другие свойства объекта конфигурации, переданные в качестве параметра, являются необязательными

new pconv2d({kernelSize: number, filters: number}), чтобы решить эту проблему.

Но, как и в случае со слоем python, pconv2d может наследоваться от tf.layers.conv2d.

Вот простой пример, демонстрирующий это

class pconv2d extends tf.layers.conv2d {
  static className = 'MyCustomLayer';

  constructor(config) {
    super(config);
    // add other initialization
  }
  // add computation of the layer
}
tf.serialization.registerClass(pconv2d);
a = tf.ones([16, 16, 16, 16])
b = new MyCustomLayer({kernelSize: 2, filters: 2}).apply(a)
b.print()
...