face-api/src/xception/extractParamsFromWeightMap.ts

import * as tf from '../../dist/tfjs.esm';

import { disposeUnusedWeightTensors, extractWeightEntryFactory, loadSeparableConvParamsFactory, ParamMapping } from '../common/index';
import { loadConvParamsFactory } from '../common/loadConvParamsFactory';
import { range } from '../utils/index';
import { MainBlockParams, ReductionBlockParams, TinyXceptionParams } from './types';

function loadParamsFactory(weightMap: any, paramMappings: ParamMapping[]) {
  const extractWeightEntry = extractWeightEntryFactory(weightMap, paramMappings);

  const extractConvParams = loadConvParamsFactory(extractWeightEntry);
  const extractSeparableConvParams = loadSeparableConvParamsFactory(extractWeightEntry);

  function extractReductionBlockParams(mappedPrefix: string): ReductionBlockParams {
    const separable_conv0 = extractSeparableConvParams(`${mappedPrefix}/separable_conv0`);
    const separable_conv1 = extractSeparableConvParams(`${mappedPrefix}/separable_conv1`);
    const expansion_conv = extractConvParams(`${mappedPrefix}/expansion_conv`);

    return { separable_conv0, separable_conv1, expansion_conv };
  }

  function extractMainBlockParams(mappedPrefix: string): MainBlockParams {
    const separable_conv0 = extractSeparableConvParams(`${mappedPrefix}/separable_conv0`);
    const separable_conv1 = extractSeparableConvParams(`${mappedPrefix}/separable_conv1`);
    const separable_conv2 = extractSeparableConvParams(`${mappedPrefix}/separable_conv2`);

    return { separable_conv0, separable_conv1, separable_conv2 };
  }

  return {
    extractConvParams,
    extractSeparableConvParams,
    extractReductionBlockParams,
    extractMainBlockParams,
  };
}

export function extractParamsFromWeightMap(
  weightMap: tf.NamedTensorMap,
  numMainBlocks: number,
): { params: TinyXceptionParams, paramMappings: ParamMapping[] } {
  const paramMappings: ParamMapping[] = [];

  const {
    extractConvParams,
    extractSeparableConvParams,
    extractReductionBlockParams,
    extractMainBlockParams,
  } = loadParamsFactory(weightMap, paramMappings);

  const entry_flow_conv_in = extractConvParams('entry_flow/conv_in');
  const entry_flow_reduction_block_0 = extractReductionBlockParams('entry_flow/reduction_block_0');
  const entry_flow_reduction_block_1 = extractReductionBlockParams('entry_flow/reduction_block_1');

  const entry_flow = {
    conv_in: entry_flow_conv_in,
    reduction_block_0: entry_flow_reduction_block_0,
    reduction_block_1: entry_flow_reduction_block_1,
  };

  const middle_flow: Record<`main_block_${number}`, MainBlockParams> = {};
  range(numMainBlocks, 0, 1).forEach((idx) => {
    middle_flow[`main_block_${idx}`] = extractMainBlockParams(`middle_flow/main_block_${idx}`);
  });

  const exit_flow_reduction_block = extractReductionBlockParams('exit_flow/reduction_block');
  const exit_flow_separable_conv = extractSeparableConvParams('exit_flow/separable_conv');

  const exit_flow = {
    reduction_block: exit_flow_reduction_block,
    separable_conv: exit_flow_separable_conv,
  };

  disposeUnusedWeightTensors(weightMap, paramMappings);

  return { params: { entry_flow, middle_flow, exit_flow }, paramMappings };
}