1 // Copyright (c) 2018, ETH Zurich and UNC Chapel Hill.
2 // All rights reserved.
3 //
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are met:
6 //
7 // * Redistributions of source code must retain the above copyright
8 // notice, this list of conditions and the following disclaimer.
9 //
10 // * Redistributions in binary form must reproduce the above copyright
11 // notice, this list of conditions and the following disclaimer in the
12 // documentation and/or other materials provided with the distribution.
13 //
14 // * Neither the name of ETH Zurich and UNC Chapel Hill nor the names of
15 // its contributors may be used to endorse or promote products derived
16 // from this software without specific prior written permission.
17 //
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
22 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 // POSSIBILITY OF SUCH DAMAGE.
29 //
30 // Author: Johannes L. Schoenberger (jsch-at-demuc-dot-de)
31
32 #include "mvs/normal_map.h"
33
34 #include "base/warp.h"
35
36 namespace colmap {
37 namespace mvs {
38
NormalMap()39 NormalMap::NormalMap() : Mat<float>(0, 0, 3) {}
40
NormalMap(const size_t width,const size_t height)41 NormalMap::NormalMap(const size_t width, const size_t height)
42 : Mat<float>(width, height, 3) {}
43
NormalMap(const Mat<float> & mat)44 NormalMap::NormalMap(const Mat<float>& mat)
45 : Mat<float>(mat.GetWidth(), mat.GetHeight(), mat.GetDepth()) {
46 CHECK_EQ(mat.GetDepth(), 3);
47 data_ = mat.GetData();
48 }
49
Rescale(const float factor)50 void NormalMap::Rescale(const float factor) {
51 if (width_ * height_ == 0) {
52 return;
53 }
54
55 const size_t new_width = std::round(width_ * factor);
56 const size_t new_height = std::round(height_ * factor);
57 std::vector<float> new_data(new_width * new_height * 3);
58
59 // Resample the normal map.
60 for (size_t d = 0; d < 3; ++d) {
61 const size_t offset = d * width_ * height_;
62 const size_t new_offset = d * new_width * new_height;
63 DownsampleImage(data_.data() + offset, height_, width_, new_height,
64 new_width, new_data.data() + new_offset);
65 }
66
67 data_ = new_data;
68 width_ = new_width;
69 height_ = new_height;
70
71 data_.shrink_to_fit();
72
73 // Re-normalize the normal vectors.
74 for (size_t r = 0; r < height_; ++r) {
75 for (size_t c = 0; c < width_; ++c) {
76 Eigen::Vector3f normal(Get(r, c, 0), Get(r, c, 1), Get(r, c, 2));
77 const float squared_norm = normal.squaredNorm();
78 if (squared_norm > 0) {
79 normal /= std::sqrt(squared_norm);
80 }
81 Set(r, c, 0, normal(0));
82 Set(r, c, 1, normal(1));
83 Set(r, c, 2, normal(2));
84 }
85 }
86 }
87
Downsize(const size_t max_width,const size_t max_height)88 void NormalMap::Downsize(const size_t max_width, const size_t max_height) {
89 if (height_ <= max_height && width_ <= max_width) {
90 return;
91 }
92 const float factor_x = static_cast<float>(max_width) / width_;
93 const float factor_y = static_cast<float>(max_height) / height_;
94 Rescale(std::min(factor_x, factor_y));
95 }
96
ToBitmap() const97 Bitmap NormalMap::ToBitmap() const {
98 CHECK_GT(width_, 0);
99 CHECK_GT(height_, 0);
100 CHECK_EQ(depth_, 3);
101
102 Bitmap bitmap;
103 bitmap.Allocate(width_, height_, true);
104
105 for (size_t y = 0; y < height_; ++y) {
106 for (size_t x = 0; x < width_; ++x) {
107 float normal[3];
108 GetSlice(y, x, normal);
109 if (normal[0] != 0 || normal[1] != 0 || normal[2] != 0) {
110 const BitmapColor<float> color(127.5f * (-normal[0] + 1),
111 127.5f * (-normal[1] + 1),
112 -255.0f * normal[2]);
113 bitmap.SetPixel(x, y, color.Cast<uint8_t>());
114 } else {
115 bitmap.SetPixel(x, y, BitmapColor<uint8_t>(0));
116 }
117 }
118 }
119
120 return bitmap;
121 }
122
123 } // namespace mvs
124 } // namespace colmap
125