akhaliq3
spaces demo
035e10c
import torch
import torch.nn as nn
from torch.nn import init
from torch.optim import lr_scheduler
def get_scheduler(optimizer, opt):
if opt.lr_policy == 'linear':
def lambda_rule(epoch):
# lr_l = 1.0 - max(0, epoch + opt.epoch_count - opt.n_epochs) / float(opt.n_epochs_decay + 1)
lr_l = 0.3 ** max(0, (epoch + opt.epoch_count - opt.n_epochs) // 5)
return lr_l
scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lambda_rule)
elif opt.lr_policy == 'step':
scheduler = lr_scheduler.StepLR(optimizer, step_size=opt.lr_decay_iters, gamma=0.1)
elif opt.lr_policy == 'plateau':
scheduler = lr_scheduler.ReduceLROnPlateau(optimizer, mode='min', factor=0.2, threshold=0.01, patience=5)
elif opt.lr_policy == 'cosine':
scheduler = lr_scheduler.CosineAnnealingLR(optimizer, T_max=opt.n_epochs, eta_min=0)
else:
return NotImplementedError('learning rate policy [%s] is not implemented', opt.lr_policy)
return scheduler
def init_weights(net, init_type='normal', init_gain=0.02):
def init_func(m):
classname = m.__class__.__name__
if hasattr(m, 'weight') and (classname.find('Conv') != -1 or classname.find('Linear') != -1):
if init_type == 'normal':
init.normal_(m.weight.data, 0.0, init_gain)
elif init_type == 'xavier':
init.xavier_normal_(m.weight.data, gain=init_gain)
elif init_type == 'kaiming':
init.kaiming_normal_(m.weight.data, a=0, mode='fan_in')
elif init_type == 'orthogonal':
init.orthogonal_(m.weight.data, gain=init_gain)
else:
raise NotImplementedError('initialization method [%s] is not implemented' % init_type)
if hasattr(m, 'bias') and m.bias is not None:
init.constant_(m.bias.data, 0.0)
elif classname.find('BatchNorm2d') != -1:
init.normal_(m.weight.data, 1.0, init_gain)
init.constant_(m.bias.data, 0.0)
print('initialize network with %s' % init_type)
net.apply(init_func)
def init_net(net, init_type='normal', init_gain=0.02, gpu_ids=()):
if len(gpu_ids) > 0:
assert (torch.cuda.is_available())
net.to(gpu_ids[0])
net = torch.nn.DataParallel(net, gpu_ids) # multi-GPUs
init_weights(net, init_type, init_gain=init_gain)
return net
class SignWithSigmoidGrad(torch.autograd.Function):
@staticmethod
def forward(ctx, x):
result = (x > 0).float()
sigmoid_result = torch.sigmoid(x)
ctx.save_for_backward(sigmoid_result)
return result
@staticmethod
def backward(ctx, grad_result):
(sigmoid_result,) = ctx.saved_tensors
if ctx.needs_input_grad[0]:
grad_input = grad_result * sigmoid_result * (1 - sigmoid_result)
else:
grad_input = None
return grad_input
class Painter(nn.Module):
def __init__(self, param_per_stroke, total_strokes, hidden_dim, n_heads=8, n_enc_layers=3, n_dec_layers=3):
super().__init__()
self.enc_img = nn.Sequential(
nn.ReflectionPad2d(1),
nn.Conv2d(3, 32, 3, 1),
nn.BatchNorm2d(32),
nn.ReLU(True),
nn.ReflectionPad2d(1),
nn.Conv2d(32, 64, 3, 2),
nn.BatchNorm2d(64),
nn.ReLU(True),
nn.ReflectionPad2d(1),
nn.Conv2d(64, 128, 3, 2),
nn.BatchNorm2d(128),
nn.ReLU(True))
self.enc_canvas = nn.Sequential(
nn.ReflectionPad2d(1),
nn.Conv2d(3, 32, 3, 1),
nn.BatchNorm2d(32),
nn.ReLU(True),
nn.ReflectionPad2d(1),
nn.Conv2d(32, 64, 3, 2),
nn.BatchNorm2d(64),
nn.ReLU(True),
nn.ReflectionPad2d(1),
nn.Conv2d(64, 128, 3, 2),
nn.BatchNorm2d(128),
nn.ReLU(True))
self.conv = nn.Conv2d(128 * 2, hidden_dim, 1)
self.transformer = nn.Transformer(hidden_dim, n_heads, n_enc_layers, n_dec_layers)
self.linear_param = nn.Sequential(
nn.Linear(hidden_dim, hidden_dim),
nn.ReLU(True),
nn.Linear(hidden_dim, hidden_dim),
nn.ReLU(True),
nn.Linear(hidden_dim, param_per_stroke))
self.linear_decider = nn.Linear(hidden_dim, 1)
self.query_pos = nn.Parameter(torch.rand(total_strokes, hidden_dim))
self.row_embed = nn.Parameter(torch.rand(8, hidden_dim // 2))
self.col_embed = nn.Parameter(torch.rand(8, hidden_dim // 2))
def forward(self, img, canvas):
b, _, H, W = img.shape
img_feat = self.enc_img(img)
canvas_feat = self.enc_canvas(canvas)
h, w = img_feat.shape[-2:]
feat = torch.cat([img_feat, canvas_feat], dim=1)
feat_conv = self.conv(feat)
pos_embed = torch.cat([
self.col_embed[:w].unsqueeze(0).contiguous().repeat(h, 1, 1),
self.row_embed[:h].unsqueeze(1).contiguous().repeat(1, w, 1),
], dim=-1).flatten(0, 1).unsqueeze(1)
hidden_state = self.transformer(pos_embed + feat_conv.flatten(2).permute(2, 0, 1).contiguous(),
self.query_pos.unsqueeze(1).contiguous().repeat(1, b, 1))
hidden_state = hidden_state.permute(1, 0, 2).contiguous()
param = self.linear_param(hidden_state)
s = hidden_state.shape[1]
grid = param[:, :, :2].view(b * s, 1, 1, 2).contiguous()
img_temp = img.unsqueeze(1).contiguous().repeat(1, s, 1, 1, 1).view(b * s, 3, H, W).contiguous()
color = nn.functional.grid_sample(img_temp, 2 * grid - 1, align_corners=False).view(b, s, 3).contiguous()
decision = self.linear_decider(hidden_state)
return torch.cat([param, color, color, torch.rand(b, s, 1, device=img.device)], dim=-1), decision