Improve Virtual Stereo Calibration

stereo_calibration/.vscode/settings.json

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+{
+    "C_Cpp.errorSquiggles": "disabled"
+}

stereo_calibration/include/calibration_checker.hpp

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+#ifndef CALIBRATION_CHECKER_HPP
+#define CALIBRATION_CHECKER_HPP
+
+#include <opencv2/opencv.hpp>
+
+typedef struct _board {
+  cv::Size board_size = {
+      0, 0};  // Number of inner corners per a chessboard row and column
+  float square_size =
+      0.0f;  // Size of a square in your defined unit (point, millimeter,etc).
+  std::vector<cv::Point3f> objp;            // 3D points in real world space
+  cv::Size2f board_size_mm = {0.0f, 0.0f};  // Physical size of the board in mm
+} Board;
+
+typedef struct _detected_board_params {
+  cv::Point2f pos = {
+      -1.0f, -1.0f};   // Normalized position of the checkerboard in the image
+  float size = -1.0f;  // Normalized size of the checkerboard
+  float skew = -1.0f;  // Normalized skew of the checkerboard
+} DetectedBoardParams;
+
+// Constants
+const size_t DEFAULT_MIN_SAMPLES = 20;
+const size_t DEFAULT_MAX_SAMPLES = 50;
+const DetectedBoardParams DEFAULT_IDEAL_PARAMS = {
+    cv::Point2f(
+        0.65f,  // Checkerboard X position should cover 65% of the image width
+        0.65f   // Checkerboard Y position should cover 65% of the image height
+        ),
+    0.4f,  // Checkerboard size variation should be at least 40%
+    0.6f   // Checkerboard skew variation should be at least 70%
+};         // Ideal parameters for a good sample database
+
+class CalibrationChecker {
+ public:
+  CalibrationChecker(cv::Size board_size, float square_size,
+                     size_t min_samples = DEFAULT_MIN_SAMPLES,
+                     size_t max_samples = DEFAULT_MAX_SAMPLES,
+                     DetectedBoardParams idealParams = DEFAULT_IDEAL_PARAMS,
+                     bool verbose = false);
+  ~CalibrationChecker() = default;
+
+  // Test if the detected corners form a valid sample
+  bool testSample(const std::vector<cv::Point2f>& corners, cv::Size image_size);
+
+  // Retrieve valid corners
+  const std::vector<std::vector<cv::Point2f>>& getValidCorners() const {
+    return validCorners_;
+  }
+
+  // Retrieve valid sample count
+  size_t getValidSampleCount() const { return validCorners_.size(); }
+
+  // Calculate the sample collection status according to the stored samples
+  bool evaluateSampleCollectionStatus(float& size_score, float& skew_score,
+                                      float& pos_score_x,
+                                      float& pos_score_y) const;
+
+  // Retrieve the last detected board parameters
+  const DetectedBoardParams& getLastDetectedBoardParams() const;
+
+ private:
+  // Calculate the parameter of a detected checkerboard
+  DetectedBoardParams getDetectedBoarParams(
+      const std::vector<cv::Point2f>& corners, cv::Size image_size);
+
+  // Check if the detected corners are valid
+  bool isGoodSample(const DetectedBoardParams& params);
+
+  // Helper functions
+  std::vector<cv::Point2f> get_outside_corners(
+      const std::vector<cv::Point2f>&
+          corners);  // Get the 4 outside corners of a checkerboard
+  float compute_skew(
+      const std::vector<cv::Point2f>&
+          outside_corners);  // Compute skew based on the 4 outside corners
+  float compute_area(
+      const std::vector<cv::Point2f>&
+          outside_corners);  // Compute area based on the 4 outside corners
+
+ private:
+  Board board_;
+
+  std::vector<DetectedBoardParams>
+      paramDb_;  // Database of previously detected board parameters
+  std::vector<std::vector<cv::Point2f>>
+      validCorners_;  // All the corners associated to the single parameters in
+                      // paramDb_
+
+  DetectedBoardParams idealParams_ = DEFAULT_IDEAL_PARAMS;
+  size_t min_samples_ = DEFAULT_MIN_SAMPLES;  // Minimum number of samples to
+                                              // consider the database complete
+  size_t max_samples_ = DEFAULT_MAX_SAMPLES;  // Maximum number of samples to
+                                              // consider the database complete
+
+  bool verbose_ = false;
+};
+
+#endif  // CALIBRATION_CHECKER_HPP