| from .pix2pix_model import Pix2PixModel |
| import torch |
| from skimage import color |
| import numpy as np |
|
|
|
|
| class ColorizationModel(Pix2PixModel): |
| """This is a subclass of Pix2PixModel for image colorization (black & white image -> colorful images). |
| |
| The model training requires '-dataset_model colorization' dataset. |
| It trains a pix2pix model, mapping from L channel to ab channels in Lab color space. |
| By default, the colorization dataset will automatically set '--input_nc 1' and '--output_nc 2'. |
| """ |
|
|
| @staticmethod |
| def modify_commandline_options(parser, is_train=True): |
| """Add new dataset-specific options, and rewrite default values for existing options. |
| |
| Parameters: |
| parser -- original option parser |
| is_train (bool) -- whether training phase or test phase. You can use this flag to add training-specific or test-specific options. |
| |
| Returns: |
| the modified parser. |
| |
| By default, we use 'colorization' dataset for this model. |
| See the original pix2pix paper (https://arxiv.org/pdf/1611.07004.pdf) and colorization results (Figure 9 in the paper) |
| """ |
| Pix2PixModel.modify_commandline_options(parser, is_train) |
| parser.set_defaults(dataset_mode="colorization") |
| return parser |
|
|
| def __init__(self, opt): |
| """Initialize the class. |
| |
| Parameters: |
| opt (Option class)-- stores all the experiment flags; needs to be a subclass of BaseOptions |
| |
| For visualization, we set 'visual_names' as 'real_A' (input real image), |
| 'real_B_rgb' (ground truth RGB image), and 'fake_B_rgb' (predicted RGB image) |
| We convert the Lab image 'real_B' (inherited from Pix2pixModel) to a RGB image 'real_B_rgb'. |
| we convert the Lab image 'fake_B' (inherited from Pix2pixModel) to a RGB image 'fake_B_rgb'. |
| """ |
| |
| Pix2PixModel.__init__(self, opt) |
| |
| self.visual_names = ["real_A", "real_B_rgb", "fake_B_rgb"] |
|
|
| def lab2rgb(self, L, AB): |
| """Convert an Lab tensor image to a RGB numpy output |
| Parameters: |
| L (1-channel tensor array): L channel images (range: [-1, 1], torch tensor array) |
| AB (2-channel tensor array): ab channel images (range: [-1, 1], torch tensor array) |
| |
| Returns: |
| rgb (RGB numpy image): rgb output images (range: [0, 255], numpy array) |
| """ |
| AB2 = AB * 110.0 |
| L2 = (L + 1.0) * 50.0 |
| Lab = torch.cat([L2, AB2], dim=1) |
| Lab = Lab[0].data.cpu().float().numpy() |
| Lab = np.transpose(Lab.astype(np.float64), (1, 2, 0)) |
| rgb = color.lab2rgb(Lab) * 255 |
| return rgb |
|
|
| def compute_visuals(self): |
| """Calculate additional output images for visdom and HTML visualization""" |
| self.real_B_rgb = self.lab2rgb(self.real_A, self.real_B) |
| self.fake_B_rgb = self.lab2rgb(self.real_A, self.fake_B) |
|
|
