// Copyright (c) 2013 libmv authors. // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to // deal in the Software without restriction, including without limitation the // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or // sell copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS // IN THE SOFTWARE. // // Author: mierle@gmail.com (Keir Mierle) // sergey.vfx@gmail.com (Sergey Sharybin) // // This is an example application which contains bundle adjustment code used // in the Libmv library and Blender. It reads problems from files passed via // the command line and runs the bundle adjuster on the problem. // // File with problem a binary file, for which it is crucial to know in which // order bytes of float values are stored in. This information is provided // by a single character in the beginning of the file. There're two possible // values of this byte: // - V, which means values in the file are stored with big endian type // - v, which means values in the file are stored with little endian type // // The rest of the file contains data in the following order: // - Space in which markers' coordinates are stored in // - Camera intrinsics // - Number of cameras // - Cameras // - Number of 3D points // - 3D points // - Number of markers // - Markers // // Markers' space could either be normalized or image (pixels). This is defined // by the single character in the file. P means markers in the file is in image // space, and N means markers are in normalized space. // // Camera intrinsics are 8 described by 8 float 8. // This values goes in the following order: // // - Focal length, principal point X, principal point Y, k1, k2, k3, p1, p2 // // Every camera is described by: // // - Image for which camera belongs to (single 4 bytes integer value). // - Column-major camera rotation matrix, 9 float values. // - Camera translation, 3-component vector of float values. // // Image number shall be greater or equal to zero. Order of cameras does not // matter and gaps are possible. // // Every 3D point is decribed by: // // - Track number point belongs to (single 4 bytes integer value). // - 3D position vector, 3-component vector of float values. // // Track number shall be greater or equal to zero. Order of tracks does not // matter and gaps are possible. // // Finally every marker is described by: // // - Image marker belongs to single 4 bytes integer value). // - Track marker belongs to single 4 bytes integer value). // - 2D marker position vector, (two float values). // // Marker's space is used a default value for refine_intrinsics command line // flag. This means if there's no refine_intrinsics flag passed via command // line, camera intrinsics will be refined if markers in the problem are // stored in image space and camera intrinsics will not be refined if markers // are in normalized space. // // Passing refine_intrinsics command line flag defines explicitly whether // refinement of intrinsics will happen. Currently, only none and all // intrinsics refinement is supported. // // There're existing problem files dumped from blender stored in folder // ../data/libmv-ba-problems. #include <cstdio> #include <fcntl.h> #include <sstream> #include <string> #include <vector> #ifdef _MSC_VER # include <io.h> # define open _open # define close _close typedef unsigned __int32 uint32_t; #else # include <stdint.h> // O_BINARY is not defined on unix like platforms, as there is no // difference between binary and text files. #define O_BINARY 0 #endif #include "ceres/ceres.h" #include "ceres/rotation.h" #include "gflags/gflags.h" #include "glog/logging.h" typedef Eigen::Matrix<double, 3, 3> Mat3; typedef Eigen::Matrix<double, 6, 1> Vec6; typedef Eigen::Vector3d Vec3; typedef Eigen::Vector4d Vec4; using std::vector; DEFINE_string(input, "", "Input File name"); DEFINE_string(refine_intrinsics, "", "Camera intrinsics to be refined. " "Options are: none, radial."); namespace { // A EuclideanCamera is the location and rotation of the camera // viewing an image. // // image identifies which image this camera represents. // R is a 3x3 matrix representing the rotation of the camera. // t is a translation vector representing its positions. struct EuclideanCamera { EuclideanCamera() : image(-1) {} EuclideanCamera(const EuclideanCamera &c) : image(c.image), R(c.R), t(c.t) {} int image; Mat3 R; Vec3 t; }; // A Point is the 3D location of a track. // // track identifies which track this point corresponds to. // X represents the 3D position of the track. struct EuclideanPoint { EuclideanPoint() : track(-1) {} EuclideanPoint(const EuclideanPoint &p) : track(p.track), X(p.X) {} int track; Vec3 X; }; // A Marker is the 2D location of a tracked point in an image. // // x and y is the position of the marker in pixels from the top left corner // in the image identified by an image. All markers for to the same target // form a track identified by a common track number. struct Marker { int image; int track; double x, y; }; // Cameras intrinsics to be bundled. // // BUNDLE_RADIAL actually implies bundling of k1 and k2 coefficients only, // no bundling of k3 is possible at this moment. enum BundleIntrinsics { BUNDLE_NO_INTRINSICS = 0, BUNDLE_FOCAL_LENGTH = 1, BUNDLE_PRINCIPAL_POINT = 2, BUNDLE_RADIAL_K1 = 4, BUNDLE_RADIAL_K2 = 8, BUNDLE_RADIAL = 12, BUNDLE_TANGENTIAL_P1 = 16, BUNDLE_TANGENTIAL_P2 = 32, BUNDLE_TANGENTIAL = 48, }; // Denotes which blocks to keep constant during bundling. // For example it is useful to keep camera translations constant // when bundling tripod motions. enum BundleConstraints { BUNDLE_NO_CONSTRAINTS = 0, BUNDLE_NO_TRANSLATION = 1, }; // The intrinsics need to get combined into a single parameter block; use these // enums to index instead of numeric constants. enum { OFFSET_FOCAL_LENGTH, OFFSET_PRINCIPAL_POINT_X, OFFSET_PRINCIPAL_POINT_Y, OFFSET_K1, OFFSET_K2, OFFSET_K3, OFFSET_P1, OFFSET_P2, }; // Returns a pointer to the camera corresponding to a image. EuclideanCamera *CameraForImage(vector<EuclideanCamera> *all_cameras, const int image) { if (image < 0 || image >= all_cameras->size()) { return NULL; } EuclideanCamera *camera = &(*all_cameras)[image]; if (camera->image == -1) { return NULL; } return camera; } const EuclideanCamera *CameraForImage( const vector<EuclideanCamera> &all_cameras, const int image) { if (image < 0 || image >= all_cameras.size()) { return NULL; } const EuclideanCamera *camera = &all_cameras[image]; if (camera->image == -1) { return NULL; } return camera; } // Returns maximal image number at which marker exists. int MaxImage(const vector<Marker> &all_markers) { if (all_markers.size() == 0) { return -1; } int max_image = all_markers[0].image; for (int i = 1; i < all_markers.size(); i++) { max_image = std::max(max_image, all_markers[i].image); } return max_image; } // Returns a pointer to the point corresponding to a track. EuclideanPoint *PointForTrack(vector<EuclideanPoint> *all_points, const int track) { if (track < 0 || track >= all_points->size()) { return NULL; } EuclideanPoint *point = &(*all_points)[track]; if (point->track == -1) { return NULL; } return point; } // Reader of binary file which makes sure possibly needed endian // conversion happens when loading values like floats and integers. // // File's endian type is reading from a first character of file, which // could either be V for big endian or v for little endian. This // means you need to design file format assuming first character // denotes file endianness in this way. class EndianAwareFileReader { public: EndianAwareFileReader(void) : file_descriptor_(-1) { // Get an endian type of the host machine. union { unsigned char bytes[4]; uint32_t value; } endian_test = { { 0, 1, 2, 3 } }; host_endian_type_ = endian_test.value; file_endian_type_ = host_endian_type_; } ~EndianAwareFileReader(void) { if (file_descriptor_ > 0) { close(file_descriptor_); } } bool OpenFile(const std::string &file_name) { file_descriptor_ = open(file_name.c_str(), O_RDONLY | O_BINARY); if (file_descriptor_ < 0) { return false; } // Get an endian tpye of data in the file. unsigned char file_endian_type_flag = Read<unsigned char>(); if (file_endian_type_flag == 'V') { file_endian_type_ = kBigEndian; } else if (file_endian_type_flag == 'v') { file_endian_type_ = kLittleEndian; } else { LOG(FATAL) << "Problem file is stored in unknown endian type."; } return true; } // Read value from the file, will switch endian if needed. template <typename T> T Read(void) const { T value; CHECK_GT(read(file_descriptor_, &value, sizeof(value)), 0); // Switch endian type if file contains data in different type // that current machine. if (file_endian_type_ != host_endian_type_) { value = SwitchEndian<T>(value); } return value; } private: static const long int kLittleEndian = 0x03020100ul; static const long int kBigEndian = 0x00010203ul; // Switch endian type between big to little. template <typename T> T SwitchEndian(const T value) const { if (sizeof(T) == 4) { unsigned int temp_value = static_cast<unsigned int>(value); return ((temp_value >> 24)) | ((temp_value << 8) & 0x00ff0000) | ((temp_value >> 8) & 0x0000ff00) | ((temp_value << 24)); } else if (sizeof(T) == 1) { return value; } else { LOG(FATAL) << "Entered non-implemented part of endian switching function."; } } int host_endian_type_; int file_endian_type_; int file_descriptor_; }; // Read 3x3 column-major matrix from the file void ReadMatrix3x3(const EndianAwareFileReader &file_reader, Mat3 *matrix) { for (int i = 0; i < 9; i++) { (*matrix)(i % 3, i / 3) = file_reader.Read<float>(); } } // Read 3-vector from file void ReadVector3(const EndianAwareFileReader &file_reader, Vec3 *vector) { for (int i = 0; i < 3; i++) { (*vector)(i) = file_reader.Read<float>(); } } // Reads a bundle adjustment problem from the file. // // file_name denotes from which file to read the problem. // camera_intrinsics will contain initial camera intrinsics values. // // all_cameras is a vector of all reconstructed cameras to be optimized, // vector element with number i will contain camera for image i. // // all_points is a vector of all reconstructed 3D points to be optimized, // vector element with number i will contain point for track i. // // all_markers is a vector of all tracked markers existing in // the problem. Only used for reprojection error calculation, stay // unchanged during optimization. // // Returns false if any kind of error happened during // reading. bool ReadProblemFromFile(const std::string &file_name, double camera_intrinsics[8], vector<EuclideanCamera> *all_cameras, vector<EuclideanPoint> *all_points, bool *is_image_space, vector<Marker> *all_markers) { EndianAwareFileReader file_reader; if (!file_reader.OpenFile(file_name)) { return false; } // Read markers' space flag. unsigned char is_image_space_flag = file_reader.Read<unsigned char>(); if (is_image_space_flag == 'P') { *is_image_space = true; } else if (is_image_space_flag == 'N') { *is_image_space = false; } else { LOG(FATAL) << "Problem file contains markers stored in unknown space."; } // Read camera intrinsics. for (int i = 0; i < 8; i++) { camera_intrinsics[i] = file_reader.Read<float>(); } // Read all cameras. int number_of_cameras = file_reader.Read<int>(); for (int i = 0; i < number_of_cameras; i++) { EuclideanCamera camera; camera.image = file_reader.Read<int>(); ReadMatrix3x3(file_reader, &camera.R); ReadVector3(file_reader, &camera.t); if (camera.image >= all_cameras->size()) { all_cameras->resize(camera.image + 1); } (*all_cameras)[camera.image].image = camera.image; (*all_cameras)[camera.image].R = camera.R; (*all_cameras)[camera.image].t = camera.t; } LOG(INFO) << "Read " << number_of_cameras << " cameras."; // Read all reconstructed 3D points. int number_of_points = file_reader.Read<int>(); for (int i = 0; i < number_of_points; i++) { EuclideanPoint point; point.track = file_reader.Read<int>(); ReadVector3(file_reader, &point.X); if (point.track >= all_points->size()) { all_points->resize(point.track + 1); } (*all_points)[point.track].track = point.track; (*all_points)[point.track].X = point.X; } LOG(INFO) << "Read " << number_of_points << " points."; // And finally read all markers. int number_of_markers = file_reader.Read<int>(); for (int i = 0; i < number_of_markers; i++) { Marker marker; marker.image = file_reader.Read<int>(); marker.track = file_reader.Read<int>(); marker.x = file_reader.Read<float>(); marker.y = file_reader.Read<float>(); all_markers->push_back(marker); } LOG(INFO) << "Read " << number_of_markers << " markers."; return true; } // Apply camera intrinsics to the normalized point to get image coordinates. // This applies the radial lens distortion to a point which is in normalized // camera coordinates (i.e. the principal point is at (0, 0)) to get image // coordinates in pixels. Templated for use with autodifferentiation. template <typename T> inline void ApplyRadialDistortionCameraIntrinsics(const T &focal_length_x, const T &focal_length_y, const T &principal_point_x, const T &principal_point_y, const T &k1, const T &k2, const T &k3, const T &p1, const T &p2, const T &normalized_x, const T &normalized_y, T *image_x, T *image_y) { T x = normalized_x; T y = normalized_y; // Apply distortion to the normalized points to get (xd, yd). T r2 = x*x + y*y; T r4 = r2 * r2; T r6 = r4 * r2; T r_coeff = (T(1) + k1*r2 + k2*r4 + k3*r6); T xd = x * r_coeff + T(2)*p1*x*y + p2*(r2 + T(2)*x*x); T yd = y * r_coeff + T(2)*p2*x*y + p1*(r2 + T(2)*y*y); // Apply focal length and principal point to get the final image coordinates. *image_x = focal_length_x * xd + principal_point_x; *image_y = focal_length_y * yd + principal_point_y; } // Cost functor which computes reprojection error of 3D point X // on camera defined by angle-axis rotation and it's translation // (which are in the same block due to optimization reasons). // // This functor uses a radial distortion model. struct OpenCVReprojectionError { OpenCVReprojectionError(const double observed_x, const double observed_y) : observed_x(observed_x), observed_y(observed_y) {} template <typename T> bool operator()(const T* const intrinsics, const T* const R_t, // Rotation denoted by angle axis // followed with translation const T* const X, // Point coordinates 3x1. T* residuals) const { // Unpack the intrinsics. const T& focal_length = intrinsics[OFFSET_FOCAL_LENGTH]; const T& principal_point_x = intrinsics[OFFSET_PRINCIPAL_POINT_X]; const T& principal_point_y = intrinsics[OFFSET_PRINCIPAL_POINT_Y]; const T& k1 = intrinsics[OFFSET_K1]; const T& k2 = intrinsics[OFFSET_K2]; const T& k3 = intrinsics[OFFSET_K3]; const T& p1 = intrinsics[OFFSET_P1]; const T& p2 = intrinsics[OFFSET_P2]; // Compute projective coordinates: x = RX + t. T x[3]; ceres::AngleAxisRotatePoint(R_t, X, x); x[0] += R_t[3]; x[1] += R_t[4]; x[2] += R_t[5]; // Compute normalized coordinates: x /= x[2]. T xn = x[0] / x[2]; T yn = x[1] / x[2]; T predicted_x, predicted_y; // Apply distortion to the normalized points to get (xd, yd). // TODO(keir): Do early bailouts for zero distortion; these are expensive // jet operations. ApplyRadialDistortionCameraIntrinsics(focal_length, focal_length, principal_point_x, principal_point_y, k1, k2, k3, p1, p2, xn, yn, &predicted_x, &predicted_y); // The error is the difference between the predicted and observed position. residuals[0] = predicted_x - T(observed_x); residuals[1] = predicted_y - T(observed_y); return true; } const double observed_x; const double observed_y; }; // Print a message to the log which camera intrinsics are gonna to be optimized. void BundleIntrinsicsLogMessage(const int bundle_intrinsics) { if (bundle_intrinsics == BUNDLE_NO_INTRINSICS) { LOG(INFO) << "Bundling only camera positions."; } else { std::string bundling_message = ""; #define APPEND_BUNDLING_INTRINSICS(name, flag) \ if (bundle_intrinsics & flag) { \ if (!bundling_message.empty()) { \ bundling_message += ", "; \ } \ bundling_message += name; \ } (void)0 APPEND_BUNDLING_INTRINSICS("f", BUNDLE_FOCAL_LENGTH); APPEND_BUNDLING_INTRINSICS("px, py", BUNDLE_PRINCIPAL_POINT); APPEND_BUNDLING_INTRINSICS("k1", BUNDLE_RADIAL_K1); APPEND_BUNDLING_INTRINSICS("k2", BUNDLE_RADIAL_K2); APPEND_BUNDLING_INTRINSICS("p1", BUNDLE_TANGENTIAL_P1); APPEND_BUNDLING_INTRINSICS("p2", BUNDLE_TANGENTIAL_P2); LOG(INFO) << "Bundling " << bundling_message << "."; } } // Print a message to the log containing all the camera intriniscs values. void PrintCameraIntrinsics(const char *text, const double *camera_intrinsics) { std::ostringstream intrinsics_output; intrinsics_output << "f=" << camera_intrinsics[OFFSET_FOCAL_LENGTH]; intrinsics_output << " cx=" << camera_intrinsics[OFFSET_PRINCIPAL_POINT_X] << " cy=" << camera_intrinsics[OFFSET_PRINCIPAL_POINT_Y]; #define APPEND_DISTORTION_COEFFICIENT(name, offset) \ { \ if (camera_intrinsics[offset] != 0.0) { \ intrinsics_output << " " name "=" << camera_intrinsics[offset]; \ } \ } (void)0 APPEND_DISTORTION_COEFFICIENT("k1", OFFSET_K1); APPEND_DISTORTION_COEFFICIENT("k2", OFFSET_K2); APPEND_DISTORTION_COEFFICIENT("k3", OFFSET_K3); APPEND_DISTORTION_COEFFICIENT("p1", OFFSET_P1); APPEND_DISTORTION_COEFFICIENT("p2", OFFSET_P2); #undef APPEND_DISTORTION_COEFFICIENT LOG(INFO) << text << intrinsics_output.str(); } // Get a vector of camera's rotations denoted by angle axis // conjuncted with translations into single block // // Element with index i matches to a rotation+translation for // camera at image i. vector<Vec6> PackCamerasRotationAndTranslation( const vector<Marker> &all_markers, const vector<EuclideanCamera> &all_cameras) { vector<Vec6> all_cameras_R_t; int max_image = MaxImage(all_markers); all_cameras_R_t.resize(max_image + 1); for (int i = 0; i <= max_image; i++) { const EuclideanCamera *camera = CameraForImage(all_cameras, i); if (!camera) { continue; } ceres::RotationMatrixToAngleAxis(&camera->R(0, 0), &all_cameras_R_t[i](0)); all_cameras_R_t[i].tail<3>() = camera->t; } return all_cameras_R_t; } // Convert cameras rotations fro mangle axis back to rotation matrix. void UnpackCamerasRotationAndTranslation( const vector<Marker> &all_markers, const vector<Vec6> &all_cameras_R_t, vector<EuclideanCamera> *all_cameras) { int max_image = MaxImage(all_markers); for (int i = 0; i <= max_image; i++) { EuclideanCamera *camera = CameraForImage(all_cameras, i); if (!camera) { continue; } ceres::AngleAxisToRotationMatrix(&all_cameras_R_t[i](0), &camera->R(0, 0)); camera->t = all_cameras_R_t[i].tail<3>(); } } void EuclideanBundleCommonIntrinsics(const vector<Marker> &all_markers, const int bundle_intrinsics, const int bundle_constraints, double *camera_intrinsics, vector<EuclideanCamera> *all_cameras, vector<EuclideanPoint> *all_points) { PrintCameraIntrinsics("Original intrinsics: ", camera_intrinsics); ceres::Problem::Options problem_options; ceres::Problem problem(problem_options); // Convert cameras rotations to angle axis and merge with translation // into single parameter block for maximal minimization speed // // Block for minimization has got the following structure: // <3 elements for angle-axis> <3 elements for translation> vector<Vec6> all_cameras_R_t = PackCamerasRotationAndTranslation(all_markers, *all_cameras); // Parameterization used to restrict camera motion for modal solvers. ceres::SubsetParameterization *constant_transform_parameterization = NULL; if (bundle_constraints & BUNDLE_NO_TRANSLATION) { std::vector<int> constant_translation; // First three elements are rotation, last three are translation. constant_translation.push_back(3); constant_translation.push_back(4); constant_translation.push_back(5); constant_transform_parameterization = new ceres::SubsetParameterization(6, constant_translation); } int num_residuals = 0; bool have_locked_camera = false; for (int i = 0; i < all_markers.size(); ++i) { const Marker &marker = all_markers[i]; EuclideanCamera *camera = CameraForImage(all_cameras, marker.image); EuclideanPoint *point = PointForTrack(all_points, marker.track); if (camera == NULL || point == NULL) { continue; } // Rotation of camera denoted in angle axis followed with // camera translaiton. double *current_camera_R_t = &all_cameras_R_t[camera->image](0); problem.AddResidualBlock(new ceres::AutoDiffCostFunction< OpenCVReprojectionError, 2, 8, 6, 3>( new OpenCVReprojectionError( marker.x, marker.y)), NULL, camera_intrinsics, current_camera_R_t, &point->X(0)); // We lock the first camera to better deal with scene orientation ambiguity. if (!have_locked_camera) { problem.SetParameterBlockConstant(current_camera_R_t); have_locked_camera = true; } if (bundle_constraints & BUNDLE_NO_TRANSLATION) { problem.SetParameterization(current_camera_R_t, constant_transform_parameterization); } num_residuals++; } LOG(INFO) << "Number of residuals: " << num_residuals; if (!num_residuals) { LOG(INFO) << "Skipping running minimizer with zero residuals"; return; } BundleIntrinsicsLogMessage(bundle_intrinsics); if (bundle_intrinsics == BUNDLE_NO_INTRINSICS) { // No camera intrinsics are being refined, // set the whole parameter block as constant for best performance. problem.SetParameterBlockConstant(camera_intrinsics); } else { // Set the camera intrinsics that are not to be bundled as // constant using some macro trickery. std::vector<int> constant_intrinsics; #define MAYBE_SET_CONSTANT(bundle_enum, offset) \ if (!(bundle_intrinsics & bundle_enum)) { \ constant_intrinsics.push_back(offset); \ } MAYBE_SET_CONSTANT(BUNDLE_FOCAL_LENGTH, OFFSET_FOCAL_LENGTH); MAYBE_SET_CONSTANT(BUNDLE_PRINCIPAL_POINT, OFFSET_PRINCIPAL_POINT_X); MAYBE_SET_CONSTANT(BUNDLE_PRINCIPAL_POINT, OFFSET_PRINCIPAL_POINT_Y); MAYBE_SET_CONSTANT(BUNDLE_RADIAL_K1, OFFSET_K1); MAYBE_SET_CONSTANT(BUNDLE_RADIAL_K2, OFFSET_K2); MAYBE_SET_CONSTANT(BUNDLE_TANGENTIAL_P1, OFFSET_P1); MAYBE_SET_CONSTANT(BUNDLE_TANGENTIAL_P2, OFFSET_P2); #undef MAYBE_SET_CONSTANT // Always set K3 constant, it's not used at the moment. constant_intrinsics.push_back(OFFSET_K3); ceres::SubsetParameterization *subset_parameterization = new ceres::SubsetParameterization(8, constant_intrinsics); problem.SetParameterization(camera_intrinsics, subset_parameterization); } // Configure the solver. ceres::Solver::Options options; options.use_nonmonotonic_steps = true; options.preconditioner_type = ceres::SCHUR_JACOBI; options.linear_solver_type = ceres::ITERATIVE_SCHUR; options.use_inner_iterations = true; options.max_num_iterations = 100; options.minimizer_progress_to_stdout = true; // Solve! ceres::Solver::Summary summary; ceres::Solve(options, &problem, &summary); std::cout << "Final report:\n" << summary.FullReport(); // Copy rotations and translations back. UnpackCamerasRotationAndTranslation(all_markers, all_cameras_R_t, all_cameras); PrintCameraIntrinsics("Final intrinsics: ", camera_intrinsics); } } // namespace int main(int argc, char **argv) { google::ParseCommandLineFlags(&argc, &argv, true); google::InitGoogleLogging(argv[0]); if (FLAGS_input.empty()) { LOG(ERROR) << "Usage: libmv_bundle_adjuster --input=blender_problem"; return EXIT_FAILURE; } double camera_intrinsics[8]; vector<EuclideanCamera> all_cameras; vector<EuclideanPoint> all_points; bool is_image_space; vector<Marker> all_markers; if (!ReadProblemFromFile(FLAGS_input, camera_intrinsics, &all_cameras, &all_points, &is_image_space, &all_markers)) { LOG(ERROR) << "Error reading problem file"; return EXIT_FAILURE; } // If there's no refine_intrinsics passed via command line // (in this case FLAGS_refine_intrinsics will be an empty string) // we use problem's settings to detect whether intrinsics // shall be refined or not. // // Namely, if problem has got markers stored in image (pixel) // space, we do full intrinsics refinement. If markers are // stored in normalized space, and refine_intrinsics is not // set, no refining will happen. // // Using command line argument refine_intrinsics will explicitly // declare which intrinsics need to be refined and in this case // refining flags does not depend on problem at all. int bundle_intrinsics = BUNDLE_NO_INTRINSICS; if (FLAGS_refine_intrinsics.empty()) { if (is_image_space) { bundle_intrinsics = BUNDLE_FOCAL_LENGTH | BUNDLE_RADIAL; } } else { if (FLAGS_refine_intrinsics == "radial") { bundle_intrinsics = BUNDLE_FOCAL_LENGTH | BUNDLE_RADIAL; } else if (FLAGS_refine_intrinsics != "none") { LOG(ERROR) << "Unsupported value for refine-intrinsics"; return EXIT_FAILURE; } } // Run the bundler. EuclideanBundleCommonIntrinsics(all_markers, bundle_intrinsics, BUNDLE_NO_CONSTRAINTS, camera_intrinsics, &all_cameras, &all_points); return EXIT_SUCCESS; }