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Running
on
Zero
| ''' | |
| # -------------------------------------------------------------------------------- | |
| # Color fixed script from Li Yi (https://github.com/pkuliyi2015/sd-webui-stablesr/blob/master/srmodule/colorfix.py) | |
| # -------------------------------------------------------------------------------- | |
| ''' | |
| import torch | |
| from PIL import Image | |
| from torch import Tensor | |
| from torch.nn import functional as F | |
| from torchvision.transforms import ToTensor, ToPILImage | |
| def adain_color_fix(target: Image, source: Image): | |
| # Convert images to tensors | |
| to_tensor = ToTensor() | |
| target_tensor = to_tensor(target).unsqueeze(0) | |
| source_tensor = to_tensor(source).unsqueeze(0) | |
| # Apply adaptive instance normalization | |
| result_tensor = adaptive_instance_normalization(target_tensor, source_tensor) | |
| # Convert tensor back to image | |
| to_image = ToPILImage() | |
| result_image = to_image(result_tensor.squeeze(0).clamp_(0.0, 1.0)) | |
| return result_image | |
| def wavelet_color_fix(target: Image, source: Image): | |
| # Convert images to tensors | |
| to_tensor = ToTensor() | |
| target_tensor = to_tensor(target).unsqueeze(0) | |
| source_tensor = to_tensor(source).unsqueeze(0) | |
| # Apply wavelet reconstruction | |
| result_tensor = wavelet_reconstruction(target_tensor, source_tensor) | |
| # Convert tensor back to image | |
| to_image = ToPILImage() | |
| result_image = to_image(result_tensor.squeeze(0).clamp_(0.0, 1.0)) | |
| return result_image | |
| def calc_mean_std(feat: Tensor, eps=1e-5): | |
| """Calculate mean and std for adaptive_instance_normalization. | |
| Args: | |
| feat (Tensor): 4D tensor. | |
| eps (float): A small value added to the variance to avoid | |
| divide-by-zero. Default: 1e-5. | |
| """ | |
| size = feat.size() | |
| assert len(size) == 4, 'The input feature should be 4D tensor.' | |
| b, c = size[:2] | |
| feat_var = feat.reshape(b, c, -1).var(dim=2) + eps | |
| feat_std = feat_var.sqrt().reshape(b, c, 1, 1) | |
| feat_mean = feat.reshape(b, c, -1).mean(dim=2).reshape(b, c, 1, 1) | |
| return feat_mean, feat_std | |
| def adaptive_instance_normalization(content_feat:Tensor, style_feat:Tensor): | |
| """Adaptive instance normalization. | |
| Adjust the reference features to have the similar color and illuminations | |
| as those in the degradate features. | |
| Args: | |
| content_feat (Tensor): The reference feature. | |
| style_feat (Tensor): The degradate features. | |
| """ | |
| size = content_feat.size() | |
| style_mean, style_std = calc_mean_std(style_feat) | |
| content_mean, content_std = calc_mean_std(content_feat) | |
| normalized_feat = (content_feat - content_mean.expand(size)) / content_std.expand(size) | |
| return normalized_feat * style_std.expand(size) + style_mean.expand(size) | |
| def wavelet_blur(image: Tensor, radius: int): | |
| """ | |
| Apply wavelet blur to the input tensor. | |
| """ | |
| # input shape: (1, 3, H, W) | |
| # convolution kernel | |
| kernel_vals = [ | |
| [0.0625, 0.125, 0.0625], | |
| [0.125, 0.25, 0.125], | |
| [0.0625, 0.125, 0.0625], | |
| ] | |
| kernel = torch.tensor(kernel_vals, dtype=image.dtype, device=image.device) | |
| # add channel dimensions to the kernel to make it a 4D tensor | |
| kernel = kernel[None, None] | |
| # repeat the kernel across all input channels | |
| kernel = kernel.repeat(3, 1, 1, 1) | |
| image = F.pad(image, (radius, radius, radius, radius), mode='replicate') | |
| # apply convolution | |
| output = F.conv2d(image, kernel, groups=3, dilation=radius) | |
| return output | |
| def wavelet_decomposition(image: Tensor, levels=5): | |
| """ | |
| Apply wavelet decomposition to the input tensor. | |
| This function only returns the low frequency & the high frequency. | |
| """ | |
| high_freq = torch.zeros_like(image) | |
| for i in range(levels): | |
| radius = 2 ** i | |
| low_freq = wavelet_blur(image, radius) | |
| high_freq += (image - low_freq) | |
| image = low_freq | |
| return high_freq, low_freq | |
| def wavelet_reconstruction(content_feat:Tensor, style_feat:Tensor): | |
| """ | |
| Apply wavelet decomposition, so that the content will have the same color as the style. | |
| """ | |
| # calculate the wavelet decomposition of the content feature | |
| content_high_freq, content_low_freq = wavelet_decomposition(content_feat) | |
| del content_low_freq | |
| # calculate the wavelet decomposition of the style feature | |
| style_high_freq, style_low_freq = wavelet_decomposition(style_feat) | |
| del style_high_freq | |
| # reconstruct the content feature with the style's high frequency | |
| return content_high_freq + style_low_freq |