SDK Calibration Configs¶

struct
Metavision
::
BlinkingDotsGridDetectorAlgorithmConfig
¶ Structure containing the configuration to initialize a BlinkingDotsGridDetectorAlgorithm.
Public Members

timestamp
processing_timestep
= 0¶ Determines the output periodicity of the algorithm. The callback will be called every processing_timestep microseconds. If set to 0, the execution will be synchronous, meaning that the callback will always be called once at the end of each call to BlinkingDotsGridDetectorAlgorithm::process_events.

int
num_rows
= 0¶ Number of horizontal lines of points in the grid.

int
num_cols
= 0¶ Number of vertical lines of points in the grid.

float
square_size
= 1.f¶ Size of a square of the grid.

float
special_freq
= 0.f¶ Special frequency, frequency of the first row of the grid, in Hz.

float
normal_freq
= 0.f¶ Normal frequency, in Hz.

timestamp
period_diff_thresh_us
= 2000¶ For the frequency estimation, the maximum difference between two successive periods to be considered the same (in us).

int
frequency_filter_length
= 7¶ Minimum number of successive stable periods to validate a frequency.

float
cluster_center_filter_alpha
= 0.05f¶ Filter constant for the position of the center of the cluster. This value must be > 0 and <=1. Values closer to 1 produce a more reactive, but noisier position estimation.

float
max_cluster_frequency_diff
= 10.f¶ Maximum difference to add a frequency event to a cluster, in Hz.

int
min_cluster_size
= 20¶ Minimum size of a frequency cluster to be used (in pixels). For a LED grid, larger values can help filtering small clusters produced by reflections, but might prevent detection when the leds are far away.

timestamp

struct
Metavision
::
BlinkingFrameGeneratorAlgorithmConfig
¶ Structure to instantiate a Blinking Detector configuration.
Public Functions

BlinkingFrameGeneratorAlgorithmConfig
(double accumulation_time, int min_num_blinking_pixels = 100, double blinking_pixels_ratios_on = 0.15, double blinking_pixels_ratios_off = 0.15, int median_blur_radius = 1)¶ Constructor.
 Parameters
accumulation_time
: Window of time during which events are considered to detect if a pixel is “blinking”min_num_blinking_pixels
: Minimum number of pixels needed to be detected before outputting a frameblinking_pixels_ratios_on
: The acceptable ratio of pixels that received only positive events over the number of pixels that received both during the accumulation windowblinking_pixels_ratios_off
: The acceptable ratio of pixels that received only negative events over the number of pixels that received both during the accumulation windowmedian_blur_radius
: Radius of the median blur applied on the mask of positive and negative pixels. a negative value disables the median blur. (diameter = 1 + 2*radius)
Public Members

unsigned int
median_blur_diameter_
¶ Diameter of the median blur applied on the mask of positive and negative pixels (diameter = 1 + 2*radius) a zero value disables the median blur.


struct
Metavision
::
DftHighFreqScorerAlgorithmConfig
¶ Structure to instantiate a DftHighFreqScorerAlgorithm configuration.
Public Functions

DftHighFreqScorerAlgorithmConfig
(timestamp refresh_period_us = 1e4, bool use_inverted_gray = false, bool speed_up = false, double high_pass_filter_dft_rows_ratio = 1.0 / 8)¶ Constructor.
 Parameters
refresh_period_us
: Time period between two consecutive process (Skip the blinking frames that are too close in time to the last one processed)use_inverted_gray
: Invert the graylevels so that white becomes black (and conversely) If true, map linearly 0 to 255 and 255 to 0; if false, keep the pixel intensity.speed_up
: Skip the process if the frame hasn’t changedhigh_pass_filter_dft_rows_ratio
: Ratio of the image’s height determining the radius for the High Pass Filter on the DFT (Ex: if ratio = 1/8 and (width,height) = (640,480), then radius = 480/8 = 60 for the filter)
