File size: 6,485 Bytes
8d34f50
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
import torch
import torch.nn as nn
import render_util
import geo_transform
import numpy as np


def compute_tri_normal(geometry, tris):
    geometry = geometry.permute(0, 2, 1)
    tri_1 = tris[:, 0]
    tri_2 = tris[:, 1]
    tri_3 = tris[:, 2]

    vert_1 = torch.index_select(geometry, 2, tri_1)
    vert_2 = torch.index_select(geometry, 2, tri_2)
    vert_3 = torch.index_select(geometry, 2, tri_3)

    nnorm = torch.cross(vert_2-vert_1, vert_3-vert_1, 1)
    normal = nn.functional.normalize(nnorm).permute(0, 2, 1)
    return normal


class Compute_normal_base(torch.autograd.Function):
    @staticmethod
    def forward(ctx, normal):
        normal_b, = render_util.normal_base_forward(normal)
        ctx.save_for_backward(normal)
        return normal_b

    @staticmethod
    def backward(ctx, grad_normal_b):
        normal, = ctx.saved_tensors
        grad_normal, = render_util.normal_base_backward(grad_normal_b, normal)
        return grad_normal


class Normal_Base(torch.nn.Module):
    def __init__(self):
        super(Normal_Base, self).__init__()

    def forward(self, normal):
        return Compute_normal_base.apply(normal)


def preprocess_render(geometry, euler, trans, cam, tris, vert_tris, ori_img):
    point_num = geometry.shape[1]
    rott_geo = geo_transform.euler_trans_geo(geometry, euler, trans)
    proj_geo = geo_transform.proj_geo(rott_geo, cam)
    rot_tri_normal = compute_tri_normal(rott_geo, tris)
    rot_vert_normal = torch.index_select(rot_tri_normal, 1, vert_tris)
    is_visible = -torch.bmm(rot_vert_normal.reshape(-1, 1, 3),
                            nn.functional.normalize(rott_geo.reshape(-1, 3, 1))).reshape(-1, point_num)
    is_visible[is_visible < 0.01] = -1
    pixel_valid = torch.zeros((ori_img.shape[0], ori_img.shape[1]*ori_img.shape[2]),
                              dtype=torch.float32, device=ori_img.device)
    return rott_geo, proj_geo, rot_tri_normal, is_visible, pixel_valid


class Render_Face(torch.autograd.Function):
    @staticmethod
    def forward(ctx, proj_geo, texture, nbl, ori_img, is_visible, tri_inds,
                pixel_valid):
        batch_size, h, w, _ = ori_img.shape
        ori_img = ori_img.view(batch_size, -1, 3)
        ori_size = torch.cat((torch.ones((batch_size, 1), dtype=torch.int32, device=ori_img.device)*h,
                              torch.ones((batch_size, 1), dtype=torch.int32, device=ori_img.device)*w),
                             dim=1).view(-1)
        tri_index, tri_coord, render, real = render_util.render_face_forward(
            proj_geo, ori_img, ori_size, texture, nbl, is_visible, tri_inds, pixel_valid)
        ctx.save_for_backward(ori_img, ori_size, proj_geo, texture, nbl,
                              tri_inds, tri_index, tri_coord)
        return render, real

    @staticmethod
    def backward(ctx, grad_render, grad_real):
        ori_img, ori_size, proj_geo, texture, nbl, tri_inds, tri_index, tri_coord = \
            ctx.saved_tensors
        grad_proj_geo, grad_texture, grad_nbl = render_util.render_face_backward(
            grad_render, grad_real, ori_img, ori_size, proj_geo, texture, nbl, tri_inds,
            tri_index, tri_coord)
        return grad_proj_geo, grad_texture, grad_nbl, None, None, None, None


class Render_RGB(nn.Module):
    def __init__(self):
        super(Render_RGB, self).__init__()

    def forward(self, proj_geo, texture, nbl, ori_img, is_visible, tri_inds, pixel_valid):
        return Render_Face.apply(proj_geo, texture, nbl, ori_img, is_visible,
                                 tri_inds, pixel_valid)


def cal_land(proj_geo, is_visible, lands_info, land_num):
    land_index, = render_util.update_contour(
        lands_info, is_visible, land_num)
    proj_land = torch.index_select(
        proj_geo.reshape(-1, 3), 0, land_index)[:, :2].reshape(-1, land_num, 2)
    return proj_land


class Render_Land(nn.Module):
    def __init__(self):
        super(Render_Land, self).__init__()
        lands_info = np.loadtxt('../data/3DMM/lands_info.txt', dtype=np.int32)
        self.lands_info = torch.as_tensor(lands_info).cuda()
        tris = np.loadtxt('../data/3DMM/tris.txt', dtype=np.int64)
        self.tris = torch.as_tensor(tris).cuda() - 1
        vert_tris = np.loadtxt('../data/3DMM/vert_tris.txt', dtype=np.int64)
        self.vert_tris = torch.as_tensor(vert_tris).cuda()
        self.normal_baser = Normal_Base().cuda()
        self.renderer = Render_RGB().cuda()

    def render_mesh(self, geometry, euler, trans, cam, ori_img, light):
        batch_size, h, w, _ = ori_img.shape
        ori_img = ori_img.view(batch_size, -1, 3)
        ori_size = torch.cat((torch.ones((batch_size, 1), dtype=torch.int32, device=ori_img.device)*h,
                              torch.ones((batch_size, 1), dtype=torch.int32, device=ori_img.device)*w),
                             dim=1).view(-1)
        rott_geo, proj_geo, rot_tri_normal, _, _ = preprocess_render(
            geometry, euler, trans, cam, self.tris, self.vert_tris, ori_img)
        tri_nb = self.normal_baser(rot_tri_normal.contiguous())
        nbl = torch.bmm(tri_nb, (light.reshape(-1, 9, 3))
                        [:, :, 0].unsqueeze(-1).repeat(1, 1, 3))
        texture = torch.ones_like(geometry) * 200
        render, = render_util.render_mesh(
            proj_geo, ori_img, ori_size, texture, nbl, self.tris)
        return render.view(batch_size, h, w, 3).byte()

    def cal_loss_rgb(self, geometry, euler, trans, cam, ori_img, light, texture, lands):
        rott_geo, proj_geo, rot_tri_normal, is_visible, pixel_valid = \
            preprocess_render(geometry, euler, trans, cam,
                              self.tris, self.vert_tris, ori_img)
        tri_nb = self.normal_baser(rot_tri_normal.contiguous())
        nbl = torch.bmm(tri_nb, light.reshape(-1, 9, 3))
        render, real = self.renderer(
            proj_geo, texture, nbl, ori_img, is_visible, self.tris, pixel_valid)
        proj_land = cal_land(proj_geo, is_visible,
                             self.lands_info, lands.shape[1])
        col_minus = torch.norm((render-real).reshape(-1, 3),
                               dim=1).reshape(ori_img.shape[0], -1)
        col_dis = torch.mean(col_minus*pixel_valid) / \
            (torch.mean(pixel_valid)+0.00001)
        land_dists = torch.norm(
            (proj_land-lands).reshape(-1, 2), dim=1).reshape(ori_img.shape[0], -1)
        lan_dis = torch.mean(land_dists)
        return col_dis, lan_dis