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 #ifndef COLMAP_SRC_BASE_WARP_H_ 33 #define COLMAP_SRC_BASE_WARP_H_ 34 35 #include "base/camera.h" 36 #include "util/alignment.h" 37 #include "util/bitmap.h" 38 39 namespace colmap { 40 41 // Warp source image to target image by projecting the pixels of the target 42 // image up to infinity and projecting it down into the source image 43 // (i.e. an inverse mapping). The function allocates the target image. 44 void WarpImageBetweenCameras(const Camera& source_camera, 45 const Camera& target_camera, 46 const Bitmap& source_image, Bitmap* target_image); 47 48 // Warp an image with the given homography, where H defines the pixel mapping 49 // from the target to source image. Note that the pixel centers are assumed to 50 // have coordinates (0.5, 0.5). 51 void WarpImageWithHomography(const Eigen::Matrix3d& H, 52 const Bitmap& source_image, Bitmap* target_image); 53 54 // First, warp source image to target image by projecting the pixels of the 55 // target image up to infinity and projecting it down into the source image 56 // (i.e. an inverse mapping). Second, warp the coordinates from the first 57 // warping with the given homography. The function allocates the target image. 58 void WarpImageWithHomographyBetweenCameras(const Eigen::Matrix3d& H, 59 const Camera& source_camera, 60 const Camera& target_camera, 61 const Bitmap& source_image, 62 Bitmap* target_image); 63 64 // Resample row-major image using bilinear interpolation. 65 void ResampleImageBilinear(const float* data, const int rows, const int cols, 66 const int new_rows, const int new_cols, 67 float* resampled); 68 69 // Smooth row-major image using a Gaussian filter kernel. 70 void SmoothImage(const float* data, const int rows, const int cols, 71 const float sigma_r, const float sigma_c, float* smoothed); 72 73 // Downsample row-major image by first smoothing and then resampling. 74 void DownsampleImage(const float* data, const int rows, const int cols, 75 const int new_rows, const int new_cols, 76 float* downsampled); 77 78 } // namespace colmap 79 80 #endif // COLMAP_SRC_BASE_WARP_H_ 81