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import torch |
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import torch.nn as nn |
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import torch.nn.functional as F |
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from model.warplayer import warp |
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from model.refine import * |
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def deconv(in_planes, out_planes, kernel_size=4, stride=2, padding=1): |
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return nn.Sequential( |
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torch.nn.ConvTranspose2d(in_channels=in_planes, out_channels=out_planes, kernel_size=4, stride=2, padding=1), |
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nn.PReLU(out_planes) |
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) |
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def conv(in_planes, out_planes, kernel_size=3, stride=1, padding=1, dilation=1): |
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return nn.Sequential( |
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nn.Conv2d(in_planes, out_planes, kernel_size=kernel_size, stride=stride, |
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padding=padding, dilation=dilation, bias=True), |
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nn.PReLU(out_planes) |
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) |
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class IFBlock(nn.Module): |
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def __init__(self, in_planes, c=64): |
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super(IFBlock, self).__init__() |
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self.conv0 = nn.Sequential( |
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conv(in_planes, c//2, 3, 2, 1), |
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conv(c//2, c, 3, 2, 1), |
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) |
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self.convblock = nn.Sequential( |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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conv(c, c), |
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) |
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self.lastconv = nn.ConvTranspose2d(c, 5, 4, 2, 1) |
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def forward(self, x, flow, scale): |
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if scale != 1: |
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x = F.interpolate(x, scale_factor = 1. / scale, mode="bilinear", align_corners=False) |
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if flow != None: |
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flow = F.interpolate(flow, scale_factor = 1. / scale, mode="bilinear", align_corners=False) * 1. / scale |
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x = torch.cat((x, flow), 1) |
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x = self.conv0(x) |
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x = self.convblock(x) + x |
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tmp = self.lastconv(x) |
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tmp = F.interpolate(tmp, scale_factor = scale * 2, mode="bilinear", align_corners=False) |
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flow = tmp[:, :4] * scale * 2 |
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mask = tmp[:, 4:5] |
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return flow, mask |
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class IFNet_m(nn.Module): |
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def __init__(self): |
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super(IFNet_m, self).__init__() |
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self.block0 = IFBlock(6+1, c=240) |
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self.block1 = IFBlock(13+4+1, c=150) |
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self.block2 = IFBlock(13+4+1, c=90) |
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self.block_tea = IFBlock(16+4+1, c=90) |
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self.contextnet = Contextnet() |
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self.unet = Unet() |
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def forward(self, x, scale=[4,2,1], timestep=0.5, returnflow=False): |
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timestep = (x[:, :1].clone() * 0 + 1) * timestep |
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img0 = x[:, :3] |
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img1 = x[:, 3:6] |
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gt = x[:, 6:] |
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flow_list = [] |
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merged = [] |
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mask_list = [] |
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warped_img0 = img0 |
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warped_img1 = img1 |
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flow = None |
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loss_distill = 0 |
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stu = [self.block0, self.block1, self.block2] |
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for i in range(3): |
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if flow != None: |
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flow_d, mask_d = stu[i](torch.cat((img0, img1, timestep, warped_img0, warped_img1, mask), 1), flow, scale=scale[i]) |
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flow = flow + flow_d |
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mask = mask + mask_d |
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else: |
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flow, mask = stu[i](torch.cat((img0, img1, timestep), 1), None, scale=scale[i]) |
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mask_list.append(torch.sigmoid(mask)) |
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flow_list.append(flow) |
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warped_img0 = warp(img0, flow[:, :2]) |
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warped_img1 = warp(img1, flow[:, 2:4]) |
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merged_student = (warped_img0, warped_img1) |
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merged.append(merged_student) |
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if gt.shape[1] == 3: |
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flow_d, mask_d = self.block_tea(torch.cat((img0, img1, timestep, warped_img0, warped_img1, mask, gt), 1), flow, scale=1) |
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flow_teacher = flow + flow_d |
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warped_img0_teacher = warp(img0, flow_teacher[:, :2]) |
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warped_img1_teacher = warp(img1, flow_teacher[:, 2:4]) |
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mask_teacher = torch.sigmoid(mask + mask_d) |
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merged_teacher = warped_img0_teacher * mask_teacher + warped_img1_teacher * (1 - mask_teacher) |
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else: |
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flow_teacher = None |
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merged_teacher = None |
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for i in range(3): |
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merged[i] = merged[i][0] * mask_list[i] + merged[i][1] * (1 - mask_list[i]) |
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if gt.shape[1] == 3: |
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loss_mask = ((merged[i] - gt).abs().mean(1, True) > (merged_teacher - gt).abs().mean(1, True) + 0.01).float().detach() |
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loss_distill += (((flow_teacher.detach() - flow_list[i]) ** 2).mean(1, True) ** 0.5 * loss_mask).mean() |
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if returnflow: |
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return flow |
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else: |
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c0 = self.contextnet(img0, flow[:, :2]) |
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c1 = self.contextnet(img1, flow[:, 2:4]) |
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tmp = self.unet(img0, img1, warped_img0, warped_img1, mask, flow, c0, c1) |
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res = tmp[:, :3] * 2 - 1 |
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merged[2] = torch.clamp(merged[2] + res, 0, 1) |
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return flow_list, mask_list[2], merged, flow_teacher, merged_teacher, loss_distill |
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