/// <summary>
/// Make the first measurement of a feature.
/// </summary>
/// <param name="z">The location of the feature to measure</param>
/// <param name="id">The Identifier to fill with the feature measurements</param>
/// <param name="f_m_m">The feature measurement model to use for this partially-initialised feature</param>
/// <returns></returns>
public virtual bool make_initial_measurement_of_feature(Vector z,
ref classimage_mono id,
Partially_Initialised_Feature_Measurement_Model f_m_m,
Vector patch_colour) { return (false); }
/// <summary>
/// Constructor for known features. The different number of
/// arguments differentiates it from the constructor for partially-initialised
/// features
/// </summary>
/// <param name="id">reference to the feature identifier</param>
/// <param name="?"></param>
public Feature(classimage_mono id, uint lab, uint list_pos,
Scene_Single scene, Vector y_known,
Vector xp_o,
Feature_Measurement_Model f_m_m, uint k_f_l)
{
feature_measurement_model = f_m_m;
feature_constructor_bookeeping();
identifier = id;
label = lab;
position_in_list = list_pos; // Position of new feature in list
// Save the vehicle position where this feature was acquired
xp_orig = new Vector(xp_o);
// Straighforward initialisation of state and covariances
y = y_known;
Pxy = new MatrixFixed(scene.get_motion_model().STATE_SIZE, feature_measurement_model.FEATURE_STATE_SIZE);
Pxy.Fill(0.0f);
Pyy = new MatrixFixed(feature_measurement_model.FEATURE_STATE_SIZE, feature_measurement_model.FEATURE_STATE_SIZE);
Pyy.Fill(0.0f);
int i = 0;
MatrixFixed newPyjyi_to_store;
foreach (Feature it in scene.get_feature_list_noconst())
{
if (i < position_in_list)
{
newPyjyi_to_store = new MatrixFixed(
it.get_feature_measurement_model().FEATURE_STATE_SIZE,
feature_measurement_model.FEATURE_STATE_SIZE);
//add to the list
matrix_block_list.Add(newPyjyi_to_store);
}
i++;
}
known_feature_label = (int)k_f_l;
if (feature_measurement_model.fully_initialised_flag)
{
partially_initialised_feature_measurement_model = null;
fully_initialised_feature_measurement_model =
(Fully_Initialised_Feature_Measurement_Model)feature_measurement_model;
}
else
{
fully_initialised_feature_measurement_model = null;
partially_initialised_feature_measurement_model =
(Partially_Initialised_Feature_Measurement_Model)feature_measurement_model;
}
}
/// <summary>
/// Convert a partially-initialised feature to a fully-initialised feature,
/// given information about the free parameters \vct{\lambda}.
/// The new state \vct{y}_{fi} is given by calling
/// Partially_Initialised_Feature_Measurement_Model::func_yfi_and_dyfi_by_dypi_and_dyfi_by_dlambda().
/// where the various Jacobians are returned by calls to
/// Partially_Initialised_Feature_Measurement_Model, and the covariance matrices
/// \mat{P}_{kl} are already known and stored in the class, except for
/// \mat{P}_{\vct{\lambda}}, which is passed to the function.
/// </summary>
/// <param name="lambda">The mean value for \vct{\lambda}</param>
/// <param name="Plambda">The covariance for \vct{\lambda}</param>
/// <param name="scene">The SLAM map</param>
public void convert_from_partially_to_fully_initialised(
Vector lambda, MatrixFixed Plambda, Scene_Single scene)
{
// We'll do all the work here in feature.cc though probably this only
// works with scene_single...
// We calculate new state yfi(ypi, lambda)
// New feature covariance
// Pyfiyfi = dyfi_by_dypi Pypiypi dyfi_by_dypiT +
// dyfi_by_dlambda Plambda dyfi_by_dlambdaT
// And we change cross covariances as follows:
// Pxyfi = Pxypi dyfi_by_dypiT
// Pyjyfi = Pyjypi dyfi_by_dypiT for j < i (since we only store top-right
// Pyfiyj = dyfi_by_dypi Pypiyj for j > i part of covariance matrix)
partially_initialised_feature_measurement_model.func_yfi_and_dyfi_by_dypi_and_dyfi_by_dlambda(y, lambda);
MatrixFixed dyfi_by_dypiT = partially_initialised_feature_measurement_model.get_dyfi_by_dypiRES().Transpose();
MatrixFixed dyfi_by_dlambdaT = partially_initialised_feature_measurement_model.get_dyfi_by_dlambdaRES().Transpose();
// Replace y
y = new Vector(partially_initialised_feature_measurement_model.get_yfiRES());
// Replace Pxy
Pxy = Pxy * dyfi_by_dypiT;
// Replace Pyy
MatrixFixed Pypiypi_1 = partially_initialised_feature_measurement_model.get_dyfi_by_dypiRES() *
Pyy * dyfi_by_dypiT;
MatrixFixed Pypiypi_2 = partially_initialised_feature_measurement_model.get_dyfi_by_dlambdaRES() *
Plambda * dyfi_by_dlambdaT;
Pyy = Pypiypi_1 + Pypiypi_2;
// Pyjyi elements for j < i (covariance with features before i in list)
uint i = position_in_list;
MatrixFixed m_it;
int j;
for (j = 0; j < position_in_list; j++)
{
m_it = (MatrixFixed)matrix_block_list[j];
matrix_block_list[j] = m_it * dyfi_by_dypiT;
}
Feature it;
int idx = scene.feature_list.IndexOf(this);
for (j = idx + 1; j < scene.feature_list.Count; j++)
{
it = (Feature)(scene.feature_list[j]);
it.matrix_block_list[(int)i] = partially_initialised_feature_measurement_model.get_dyfi_by_dypiRES() * (MatrixFixed)it.matrix_block_list[(int)i];
it.increment_position_in_total_state_vector(-(int)feature_measurement_model.FEATURE_STATE_SIZE);
}
// Change the total state size in scene, here with a negative increment
uint size1 = partially_initialised_feature_measurement_model.more_initialised_feature_measurement_model.FEATURE_STATE_SIZE;
uint size2 = partially_initialised_feature_measurement_model.FEATURE_STATE_SIZE;
scene.increment_total_state_size((int)size1 - (int)size2);
// Change fmm for this model to fully-initialised one
feature_measurement_model =
partially_initialised_feature_measurement_model.more_initialised_feature_measurement_model;
partially_initialised_feature_measurement_model = null;
fully_initialised_feature_measurement_model =
(Fully_Initialised_Feature_Measurement_Model)feature_measurement_model;
//assert(fully_initialised_feature_measurement_model != NULL);
// Need to reallocate any other matrices
// Assume that measurement size doesn't change
dh_by_dy.Resize(feature_measurement_model.MEASUREMENT_SIZE, feature_measurement_model.FEATURE_STATE_SIZE);
}
/// <summary>
/// Constructor for partially-initialised features.
/// </summary>
/// <param name="id">reference to the feature</param>
/// <param name="lab"></param>
/// <param name="list_pos"></param>
/// <param name="scene"></param>
/// <param name="h"></param>
/// <param name="p_i_f_m_m"></param>
public Feature(classimage_mono id, uint lab, uint list_pos,
Scene_Single scene, Vector h,
Partially_Initialised_Feature_Measurement_Model p_i_f_m_m,
Vector feature_colour)
{
feature_measurement_model = p_i_f_m_m;
partially_initialised_feature_measurement_model = p_i_f_m_m;
fully_initialised_feature_measurement_model = null;
// Stuff below substituted from Feature_common
// Feature_common(id, lab, list_pos, scene, h);
feature_constructor_bookeeping();
identifier = id;
label = lab;
position_in_list = list_pos; // Position of new feature in list
position_in_total_state_vector = 0; // This should be set properly
colour = feature_colour;
//when feature is added
// Save the vehicle position where this feature was acquired
scene.get_motion_model().func_xp(scene.get_xv());
//xp_orig = scene.get_motion_model().get_xpRES();
xp_orig = new Vector(scene.get_motion_model().get_xpRES());
// Call model functions to calculate feature state, measurement noise
// and associated Jacobians. Results are stored in RES matrices
// First calculate "position state" and Jacobian
scene.get_motion_model().func_xp(scene.get_xv());
scene.get_motion_model().func_dxp_by_dxv(scene.get_xv());
// Now ask the model to initialise the state vector and calculate Jacobians
// so that I can go and calculate the covariance matrices
partially_initialised_feature_measurement_model.func_ypi_and_dypi_by_dxp_and_dypi_by_dhi_and_Ri(h, scene.get_motion_model().get_xpRES());
// State y
//y = partially_initialised_feature_measurement_model.get_ypiRES();
y = new Vector(partially_initialised_feature_measurement_model.get_ypiRES());
// Temp_FS1 will store dypi_by_dxv
MatrixFixed Temp_FS1 =
partially_initialised_feature_measurement_model.get_dypi_by_dxpRES() *
scene.get_motion_model().get_dxp_by_dxvRES();
// Pxy
Pxy = scene.get_Pxx() * Temp_FS1.Transpose();
// Pyy
Pyy = Temp_FS1 * scene.get_Pxx() * Temp_FS1.Transpose()
+ partially_initialised_feature_measurement_model.get_dypi_by_dhiRES()
* partially_initialised_feature_measurement_model.get_RiRES()
* partially_initialised_feature_measurement_model.get_dypi_by_dhiRES().Transpose();
// Covariances of this feature with others
int j = 0;
foreach (Feature it in scene.get_feature_list_noconst())
{
if (j < position_in_list)
{
// new Pypiyj = dypi_by_dxv . Pxyj
// Size of this is FEATURE_STATE_SIZE(new) by FEATURE_STATE_SIZE(old)
MatrixFixed m = it.get_Pxy();
MatrixFixed newPyjypi_to_store = (Temp_FS1 * m).Transpose();
//add to the list
matrix_block_list.Add(newPyjypi_to_store);
}
j++;
}
known_feature_label = -1;
}
/// <summary>
/// Create a new partially-initialised feature. This creates a new Feature, and
/// creates a new empty FeatureInitInfo to store the extra initialisation
/// information, which must be then filled in by the caller of this function.
/// </summary>
/// <param name="id">The unique identifier for this feature (e.g. the image patch)</param>
/// <param name="h">The initial measured state for this feature (e.g. the image location)</param>
/// <param name="f_m_m">The partially-initialised feature measurement model to apply to this feature.</param>
/// <returns>A pointer to the FeatureInitInfo object to be filled in with further initialisation information.</returns>
public FeatureInitInfo add_new_partially_initialised_feature(classimage_mono id,
Vector h, Partially_Initialised_Feature_Measurement_Model f_m_m,
Vector feature_colour)
{
Feature nf = new Feature(id, next_free_label, (uint)feature_list.Count, this, h, f_m_m, feature_colour);
add_new_feature_bookeeping(nf);
// Set stuff to store extra probability information for partially
// initialised feature
FeatureInitInfo feat = new FeatureInitInfo(this, nf);
feature_init_info_vector.Add(feat);
return (feat);
}
/// <summary>
/// Make the initial measurement of the currently-selected feature. This fills in
/// the location and the identifier (a copy of the image patch) for the current
/// feature. The feature location is set using set_image_selection_automatically()
/// or manually by the user using set_image_selection(). This function just calls
/// partially_initialise_point_feature() to fill in the measurement and identifier.
/// </summary>
/// <param name="z">The measurement vector to be filled in.</param>
/// <param name="id_ptr">The identifier to be filled in.</param>
/// <param name="m"></param>
/// <returns>true on success, or <code>false</code> on failure (e.g. no patch is currently selected).</returns>
public override bool make_initial_measurement_of_feature(Vector z, ref byte[] patch, Partially_Initialised_Feature_Measurement_Model m, Vector patch_colour)
{
patch = partially_initialise_point_feature(z);
for (int c = 0; c < 3; c++) patch_colour[c] = image_colour.image[uu, vv, c];
if (patch != null)
return true;
else
return false;
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="initialisation_file">The initialisation file to read. This specifies the motion- and feature-measurement models to use, the initial state and known features.</param>
/// <param name="mm_creator">The factory to use to create motion models.</param>
/// <param name="fmm_creator">The factory to use to create feature measurement models</param>
/// <param name="imm_creator">The factory to use to create internal measurement models</param>
/// <param name="number_of_features_to_select">The number of features to select for measurement at each time step</param>
/// <param name="number_of_features_to_keep_visible">The requried number of visible features. If fewer than this number are visible at any time step, the creation of a new feature is initiated</param>
/// <param name="max_features_to_init_at_once"></param>
/// <param name="min_lambda">The minimum distance from the camera (in metres) for a new feature</param>
/// <param name="max_lambda">The maximum distance from the camera (in metres) for a new feature</param>
/// <param name="number_of_particles">The number of particles to use for new features (distributed evenly in space between min_lambda and max_lambda)</param>
/// <param name="standard_deviation_depth_ratio">The ratio between standard deviation and mean to use to identify when a partially-initialised feature should be converted to a fully-initialised one</param>
/// <param name="min_number_of_particles">The minimum number of particles below which a partially-initalised feature is deleted</param>
/// <param name="prune_probability_threshold">The threshold below which a particle with low probability is deleted</param>
/// <param name="erase_partially_init_feature_after_this_many_attempts">The number of failed match attempts before a partially initialised feature is deleted.</param>
public MonoSLAM(String initialisation_file,
String path,
Motion_Model_Creator mm_creator,
Feature_Measurement_Model_Creator fmm_creator,
Internal_Measurement_Model_Creator imm_creator,
uint number_of_features_to_select,
uint number_of_features_to_keep_visible,
uint max_features_to_init_at_once,
float min_lambda,
float max_lambda,
uint number_of_particles,
float standard_deviation_depth_ratio,
uint min_number_of_particles,
float prune_probability_threshold,
uint erase_partially_init_feature_after_this_many_attempts,
float MAXIMUM_ANGLE_DIFFERENCE,
float calibration_target_width_mm,
float calibration_target_height_mm,
float calibration_target_distance_mm)
{
PATH = path;
NUMBER_OF_FEATURES_TO_SELECT = number_of_features_to_select;
NUMBER_OF_FEATURES_TO_KEEP_VISIBLE = number_of_features_to_keep_visible;
MAX_FEATURES_TO_INIT_AT_ONCE = max_features_to_init_at_once;
MIN_LAMBDA = min_lambda;
MAX_LAMBDA = max_lambda;
NUMBER_OF_PARTICLES = number_of_particles;
STANDARD_DEVIATION_DEPTH_RATIO = standard_deviation_depth_ratio;
MIN_NUMBER_OF_PARTICLES = min_number_of_particles;
PRUNE_PROBABILITY_THRESHOLD = prune_probability_threshold;
ERASE_PARTIALLY_INIT_FEATURE_AFTER_THIS_MANY_ATTEMPTS = erase_partially_init_feature_after_this_many_attempts;
number_of_visible_features = 0;
number_of_matched_features = 0;
Settings settings = new Settings();
//if no file exists create some default values
//if (!File.Exists(PATH + initialisation_file))
{
//create a settings file
settings.createDefault(PATH + initialisation_file, calibration_target_width_mm,
calibration_target_height_mm, calibration_target_distance_mm);
//settings.createDefault(PATH + initialisation_file, 210, 148.5, 600);
}
//create some known features
//createDefaultKnownFeatures(PATH);
// Create the Settings class by reading from the initialisation file
if (File.Exists(PATH + initialisation_file))
{
StreamReader stream = File.OpenText(PATH + initialisation_file);
settings.load(stream);
// Create the Scene class. This also constructs the motion model and
// internal measurement models and sets the initial state
scene = new Scene_Single(settings, mm_creator, imm_creator);
// Now sort out the feature types
ArrayList values = settings.get_entry("Models", "NewFeatureMeasurementModel");
String feature_init_type = (String)values[0];
Feature_Measurement_Model fm_model =
fmm_creator.create_model(feature_init_type, scene.get_motion_model(), MAXIMUM_ANGLE_DIFFERENCE);
if (fm_model == null)
{
Debug.WriteLine("Unable to create a feature measurement motion model of type " +
feature_init_type + " as requested in initalisation file " +
initialisation_file);
}
else
{
// Initialise this motion model
fm_model.read_parameters(settings);
// Check that this is a partially-initialised feature type
if (fm_model.fully_initialised_flag)
{
Debug.WriteLine("Feature measurement motion model " + feature_init_type +
" as requested in initalisation file " + initialisation_file +
" is not a partially-initialised feature type. ");
}
default_feature_type_for_initialisation =
(Partially_Initialised_Feature_Measurement_Model)fm_model;
// We hope that features are viewed through a camera! If so,
// the feature measurement class should derive from
// Camera_Feature_Measurement_Model
// Note the multiple inherritance workaround
Camera_Feature_Measurement_Model cfmm =
(Camera_Feature_Measurement_Model)(fm_model.wide_model);
if (cfmm == null)
{
// Oops - the feature measurement model is not derived from
// Camera_Feature_Measurement_Model!
Debug.WriteLine("The default feature measurement motion model " +
fm_model.feature_type +
" is not derived from Camera_Feature_Measurement_Model!");
}
else
{
CAMERA_WIDTH = cfmm.get_camera().ImageWidth();
CAMERA_HEIGHT = cfmm.get_camera().ImageHeight();
kalman = new Kalman();
robot = new Robot();
sim_or_rob = (Sim_Or_Rob)robot;
// Initialise any known features
SceneLib.initialise_known_features(settings, fmm_creator, sim_or_rob, scene, PATH, MAXIMUM_ANGLE_DIFFERENCE);
// Various flags
init_feature_search_region_defined_flag = false;
}
}
stream.Close();
}
else
{
Debug.WriteLine("File not found: " + initialisation_file);
}
}
// Function to find a region in an image guided by current motion prediction
// which doesn't overlap existing features
public static bool FindNonOverlappingRegion(Scene_Single scene,
Vector local_u,
float delta_t,
Partially_Initialised_Feature_Measurement_Model default_feature_type_for_initialisation,
uint camera_width,
uint camera_height,
uint BOXSIZE,
ref int init_feature_search_ustart,
ref int init_feature_search_vstart,
ref int init_feature_search_ufinish,
ref int init_feature_search_vfinish,
uint FEATURE_INIT_STEPS_TO_PREDICT,
float FEATURE_INIT_DEPTH_HYPOTHESIS,
Random rnd)
{
ThreeD_Motion_Model threed_motion_model = (ThreeD_Motion_Model)scene.get_motion_model();
Vector local_xv = new Vector(scene.get_xv());
for (uint i = 0; i < FEATURE_INIT_STEPS_TO_PREDICT; i++)
{
scene.get_motion_model().func_fv_and_dfv_by_dxv(local_xv, local_u, delta_t);
local_xv.Update(scene.get_motion_model().get_fvRES());
}
threed_motion_model.func_xp(local_xv);
Vector local_xp = new Vector(threed_motion_model.get_xpRES());
threed_motion_model.func_r(local_xp);
Vector3D rW = threed_motion_model.get_rRES();
threed_motion_model.func_q(local_xp);
Quaternion qWR = threed_motion_model.get_qRES();
// yW = rW + RWR hR
Vector3D hR = new Vector3D(0.0f, 0.0f, FEATURE_INIT_DEPTH_HYPOTHESIS);
// Used Inverse + transpose because this was't compiling the normal way
Vector3D yW = new Vector3D(rW + qWR.RotationMatrix() * hR);
// Then project that point into the current camera position
scene.get_motion_model().func_xp(scene.get_xv());
Fully_Initialised_Feature_Measurement_Model fully_init_fmm =
(Fully_Initialised_Feature_Measurement_Model)(default_feature_type_for_initialisation.more_initialised_feature_measurement_model);
Vector yWVNL = yW.GetVNL3();
fully_init_fmm.func_hi_and_dhi_by_dxp_and_dhi_by_dyi(yWVNL, scene.get_motion_model().get_xpRES());
// Now, this defines roughly how much we expect a feature initialised to move
float suggested_u = fully_init_fmm.get_hiRES()[0];
float suggested_v = fully_init_fmm.get_hiRES()[1];
float predicted_motion_u = camera_width / 2.0f - suggested_u;
float predicted_motion_v = camera_height / 2.0f - suggested_v;
// So, the limits of a "safe" region within which we can initialise
// features so that they end up staying within the screen
// (Making the approximation that the whole screen moves like the
// centre point)
int safe_feature_search_ustart = (int)(-predicted_motion_u);
int safe_feature_search_vstart = (int)(-predicted_motion_v);
int safe_feature_search_ufinish = (int)(camera_width - predicted_motion_u);
int safe_feature_search_vfinish = (int)(camera_height - predicted_motion_v);
if (safe_feature_search_ustart < ((int)((BOXSIZE - 1) / 2) + 1))
safe_feature_search_ustart = (int)((BOXSIZE - 1) / 2 + 1);
if (safe_feature_search_ufinish > (int)camera_width - ((int)((BOXSIZE - 1) / 2) + 1))
safe_feature_search_ufinish = (int)(camera_width - (BOXSIZE - 1) / 2 - 1);
if (safe_feature_search_vstart < ((int)((BOXSIZE - 1) / 2) + 1))
safe_feature_search_vstart = (int)((BOXSIZE - 1) / 2 + 1);
if (safe_feature_search_vfinish > (int)camera_height - ((int)((BOXSIZE - 1) / 2) + 1))
safe_feature_search_vfinish = (int)(camera_height - (BOXSIZE - 1) / 2 - 1);
return FindNonOverlappingRegionNoPredict(safe_feature_search_ustart,
safe_feature_search_vstart,
safe_feature_search_ufinish,
safe_feature_search_vfinish,
scene,
ref init_feature_search_ustart,
ref init_feature_search_vstart,
ref init_feature_search_ufinish,
ref init_feature_search_vfinish, rnd);
}
