步骤

前向传递

后向传递

1

$x_{LT},x_{HT}=Split\left(x\right)$

${x^{\prime }}_{LT},{x^{\prime }}_{HT}=Split\left(x^{\prime }\right)$

2

${x^{\prime }}_{LT}=x_{LT}\ast \exp \left({\phi }_1\left(x_{HT}\right)\right)+{\phi }_2\left(x_{HT}\right)$

$x_{HT}=\left({x^{\prime }}_{HT}-{\phi }_4\left({x^{\prime }}_{LT}\right)\right)/\exp \left({\phi }_3\left({x^{\prime }}_{LT}\right)\right)$

3

${x^{\prime }}_{HT}=x_{HT}\ast \exp \left({\phi }_3\left({x^{\prime }}_{LT}\right)\right)+{\phi }_4\left({x^{\prime }}_{LT}\right)$

$x_{LT}=\left({x^{\prime }}_{LT}-{\phi }_2\left(x_{HT}\right)\right)/\exp \left({\phi }_1\left(x_{HT}\right)\right)$

4

$x^{\prime }=\text{Concat}\left({x^{\prime }}_{LT},{x^{\prime }}_{HT}\right)$

$x=\text{Concat}\left(x_{LT},x_{HT}\right)$