Split camera_reader into a lib and main

Change-Id: If3ace42d69d4abf2aea501457e7c0757426688c4
Signed-off-by: James Kuszmaul <jabukuszmaul@gmail.com>
diff --git a/y2020/vision/camera_reader.h b/y2020/vision/camera_reader.h
new file mode 100644
index 0000000..c05ebea
--- /dev/null
+++ b/y2020/vision/camera_reader.h
@@ -0,0 +1,174 @@
+#ifndef Y2020_VISION_CAMERA_READER_H_
+#define Y2020_VISION_CAMERA_READER_H_
+
+#include <math.h>
+
+#include <opencv2/calib3d.hpp>
+#include <opencv2/features2d.hpp>
+#include <opencv2/imgproc.hpp>
+
+#include "aos/events/event_loop.h"
+#include "aos/flatbuffer_merge.h"
+#include "aos/network/team_number.h"
+#include "y2020/vision/sift/sift971.h"
+#include "y2020/vision/sift/sift_generated.h"
+#include "y2020/vision/sift/sift_training_generated.h"
+#include "y2020/vision/tools/python_code/sift_training_data.h"
+#include "y2020/vision/v4l2_reader.h"
+#include "y2020/vision/vision_generated.h"
+
+namespace frc971 {
+namespace vision {
+
+class CameraReader {
+ public:
+  CameraReader(aos::EventLoop *event_loop,
+               const sift::TrainingData *training_data, V4L2Reader *reader,
+               const cv::Ptr<cv::flann::IndexParams> &index_params,
+               const cv::Ptr<cv::flann::SearchParams> &search_params)
+      : event_loop_(event_loop),
+        training_data_(training_data),
+        camera_calibration_(FindCameraCalibration()),
+        reader_(reader),
+        image_sender_(event_loop->MakeSender<CameraImage>("/camera")),
+        result_sender_(
+            event_loop->MakeSender<sift::ImageMatchResult>("/camera")),
+        detailed_result_sender_(
+            event_loop->MakeSender<sift::ImageMatchResult>("/camera/detailed")),
+        read_image_timer_(event_loop->AddTimer([this]() { ReadImage(); })) {
+    for (int ii = 0; ii < number_training_images(); ++ii) {
+      matchers_.push_back(cv::FlannBasedMatcher(index_params, search_params));
+      prev_camera_field_R_vec_list_.push_back(cv::Mat::zeros(3, 1, CV_32F));
+      prev_camera_field_T_list_.push_back(cv::Mat::zeros(3, 1, CV_32F));
+    }
+    CopyTrainingFeatures();
+
+    for (auto &matcher : matchers_) {
+      matcher.train();
+    }
+
+    event_loop->OnRun(
+        [this]() { read_image_timer_->Setup(event_loop_->monotonic_now()); });
+  }
+
+ private:
+  const sift::CameraCalibration *FindCameraCalibration() const;
+
+  // Copies the information from training_data_ into matcher_.
+  void CopyTrainingFeatures();
+  // Processes an image (including sending the results).
+  void ProcessImage(const CameraImage &image);
+  // Reads an image, and then performs all of our processing on it.
+  void ReadImage();
+
+  flatbuffers::Offset<
+      flatbuffers::Vector<flatbuffers::Offset<sift::ImageMatch>>>
+  PackImageMatches(flatbuffers::FlatBufferBuilder *fbb,
+                   const std::vector<std::vector<cv::DMatch>> &matches);
+  flatbuffers::Offset<flatbuffers::Vector<flatbuffers::Offset<sift::Feature>>>
+  PackFeatures(flatbuffers::FlatBufferBuilder *fbb,
+               const std::vector<cv::KeyPoint> &keypoints,
+               const cv::Mat &descriptors);
+
+  void SendImageMatchResult(const CameraImage &image,
+                            const std::vector<cv::KeyPoint> &keypoints,
+                            const cv::Mat &descriptors,
+                            const std::vector<std::vector<cv::DMatch>> &matches,
+                            const std::vector<cv::Mat> &camera_target_list,
+                            const std::vector<cv::Mat> &field_camera_list,
+                            const std::vector<cv::Point2f> &target_point_vector,
+                            const std::vector<float> &target_radius_vector,
+                            const std::vector<int> &training_image_indices,
+                            const std::vector<int> &homography_feature_counts,
+                            aos::Sender<sift::ImageMatchResult> *result_sender,
+                            bool send_details);
+
+  // Returns the 2D (image) location for the specified training feature.
+  cv::Point2f Training2dPoint(int training_image_index,
+                              int feature_index) const {
+    const float x = training_data_->images()
+                        ->Get(training_image_index)
+                        ->features()
+                        ->Get(feature_index)
+                        ->x();
+    const float y = training_data_->images()
+                        ->Get(training_image_index)
+                        ->features()
+                        ->Get(feature_index)
+                        ->y();
+    return cv::Point2f(x, y);
+  }
+
+  // Returns the 3D location for the specified training feature.
+  cv::Point3f Training3dPoint(int training_image_index,
+                              int feature_index) const {
+    const sift::KeypointFieldLocation *const location =
+        training_data_->images()
+            ->Get(training_image_index)
+            ->features()
+            ->Get(feature_index)
+            ->field_location();
+    return cv::Point3f(location->x(), location->y(), location->z());
+  }
+
+  const sift::TransformationMatrix *FieldToTarget(int training_image_index) {
+    return training_data_->images()
+        ->Get(training_image_index)
+        ->field_to_target();
+  }
+
+  void TargetLocation(int training_image_index, cv::Point2f &target_location,
+                      float &target_radius) {
+    target_location.x =
+        training_data_->images()->Get(training_image_index)->target_point_x();
+    target_location.y =
+        training_data_->images()->Get(training_image_index)->target_point_y();
+    target_radius = training_data_->images()
+                        ->Get(training_image_index)
+                        ->target_point_radius();
+  }
+
+  int number_training_images() const {
+    return training_data_->images()->size();
+  }
+
+  cv::Mat CameraIntrinsics() const {
+    const cv::Mat result(3, 3, CV_32F,
+                         const_cast<void *>(static_cast<const void *>(
+                             camera_calibration_->intrinsics()->data())));
+    CHECK_EQ(result.total(), camera_calibration_->intrinsics()->size());
+    return result;
+  }
+
+  cv::Mat CameraDistCoeffs() const {
+    const cv::Mat result(5, 1, CV_32F,
+                         const_cast<void *>(static_cast<const void *>(
+                             camera_calibration_->dist_coeffs()->data())));
+    CHECK_EQ(result.total(), camera_calibration_->dist_coeffs()->size());
+    return result;
+  }
+
+  aos::EventLoop *const event_loop_;
+  const sift::TrainingData *const training_data_;
+  const sift::CameraCalibration *const camera_calibration_;
+  V4L2Reader *const reader_;
+  std::vector<cv::FlannBasedMatcher> matchers_;
+  aos::Sender<CameraImage> image_sender_;
+  aos::Sender<sift::ImageMatchResult> result_sender_;
+  aos::SendFailureCounter result_failure_counter_;
+  aos::Sender<sift::ImageMatchResult> detailed_result_sender_;
+  // We schedule this immediately to read an image. Having it on a timer means
+  // other things can run on the event loop in between.
+  aos::TimerHandler *const read_image_timer_;
+
+  // Storage for when we want to use the previous estimates of pose
+  std::vector<cv::Mat> prev_camera_field_R_vec_list_;
+  std::vector<cv::Mat> prev_camera_field_T_list_;
+
+  const std::unique_ptr<frc971::vision::SIFT971_Impl> sift_{
+      new frc971::vision::SIFT971_Impl()};
+};
+
+}  // namespace vision
+}  // namespace frc971
+#endif  // Y2020_VISION_CAMERA_READER_H_