discriminatorModel.py

import torch
import torch.nn as nn

# The Discriminator model
class Discriminator(nn.Module):
    def __init__(self, channels, embed_dim=1024, embed_out_dim=128):
        super(Discriminator, self).__init__()
        self.channels = channels
        self.embed_dim = embed_dim
        self.embed_out_dim = embed_out_dim

        # Discriminator architecture
        self.model = nn.Sequential(
            *self._create_layer(self.channels, 32, 4, 2, 1, normalize=False),
            *self._create_layer(32, 64, 4, 2, 1),
            *self._create_layer(64, 128, 4, 2, 1),
            *self._create_layer(128, 256, 4, 2, 1),
            *self._create_layer(256, 512, 4, 2, 1)
        )
        self.text_embedding = Embedding(self.embed_dim, self.embed_out_dim)  # Text embedding module
        self.output = nn.Sequential(
            nn.Conv2d(512 + self.embed_out_dim, 1, 4, 1, 0, bias=False), nn.Sigmoid()
        )

    def _create_layer(self, size_in, size_out, kernel_size=4, stride=2, padding=1, normalize=True):
        layers = [nn.Conv2d(size_in, size_out, kernel_size=kernel_size, stride=stride, padding=padding)]
        if normalize:
            layers.append(nn.BatchNorm2d(size_out))
        layers.append(nn.LeakyReLU(0.2, inplace=True))
        return layers

    def forward(self, x, text):
        x_out = self.model(x)  # Extract features from the input using the discriminator architecture
        out = self.text_embedding(x_out, text)  # Apply text embedding and concatenate with the input features
        out = self.output(out)  # Final discriminator output
        return out.squeeze(), x_out