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classLaserSensingTrajectory.cpp
- Committer:
- mbedalvaro
- Date:
- 2014-12-02
- Revision:
- 48:7633d8e7b0d3
- Parent:
- 45:a3b984a79d5d
File content as of revision 48:7633d8e7b0d3:
#include "classLaserSensingTrajectory.h" using namespace std; LaserSensingTrajectory::LaserSensingTrajectory():lightTouched(false), lightState(ALL_DARK), min_contrast_ratio(MIN_CONTRAST_RATIO), threshold_factor(THRESHOLD_FACTOR), min_acceptable_intensity(MIN_ACCEPTABLE_INTENSITY), fixedThreshold(FIXED_THRESHOLD), delayMirrorSamples(0) { lsdTrajectory.clear(); // no need in principle! the constructor of the vector will give an empty vector! // attention: properly set the state of the threshold switch in the IO.init (which by the way, in THIS hardware // implementation indicates the state for ALL the objects..) modeThreshold=AUTO; // IO.setSwitchOneState(true); } LaserSensingTrajectory::~LaserSensingTrajectory() { // lsdTrajectory.clear(); // there is no need to clear the vector, the destructor of this vector is called by default (and it's NOT a vector of pointers) } void LaserSensingTrajectory::setDelayMirrors(int delay) { delayMirrorSamples=delay; } void LaserSensingTrajectory::addDelayMirrors(int add_delay) { delayMirrorSamples+=add_delay; } bool LaserSensingTrajectory::processSensedData() { // Compute max and min intensity on the loop maxI=0; minI=255; // ratio has been normalized between 0 and 255 unsigned short auxSize=lsdTrajectory.size(); // could be an unsigned char in principle... no more than 255 points per object, but well, memory in future versions // of the microprocessor can be larger. // Compute minimum and maximum intensities: for (unsigned short i = 0; i < auxSize; i++) { unsigned char mesI=lsdTrajectory[i].intensity; if (maxI<mesI) maxI=mesI; if (minI>mesI) minI=mesI; } // Compute autoThreshold: switch(modeThreshold) { case AUTO: if (minI==0) minI=1; if (maxI<min_acceptable_intensity) autoThreshold=255;// (we consider that the saccade is FULL on something black - this is noise) else if (1.0*maxI/minI > min_contrast_ratio ) { autoThreshold = (unsigned char) (1.0 * (maxI-minI) * threshold_factor + minI); // threshold_factor = 2/3 or 1/2 is a good value. } else {// ... otherwise, we consider that the saccade is FULL on something WHITE (convention...) autoThreshold=0; } break; case FIXED: autoThreshold=fixedThreshold; break; } // Segment the trajectory (only two levels for the time being, but we can have more - meaning different forces, real or even complex values to have different angle forces...): // NOTE: if using 1 and -1 instead of 1 and 0, we can avoid having to add a "blob internal pressure"! -1 means a force towards the interior, and +1 outwards... // This means that the loop will naturally become inside-out depending on the color of the main surface! (but will mantain its normal size). Much better and elegant solution than the // idea of the blob "constant" internal pressure... bool isLightZone=false, isDarkZone=false; for (unsigned short i = 0; i < auxSize; i++) { unsigned short delayedpoint=(i+auxSize+delayMirrorSamples)%auxSize; // this way we can have negative delayMirrorSamples if required (would be absurd though) if (lsdTrajectory[delayedpoint].intensity>=autoThreshold) { // this means a WHITE zone: lsdTrajectory[i].lightZone= -1; isLightZone=true; } else { // this means DARK ZONE lsdTrajectory[i].lightZone= 2; isDarkZone=true; } } // In the case of AUTO mode, we assume that something is touching the object when the trajectory has at least one light zone and one dark zone; // in the case of FIXED mode, we assume something is touching the object when there is at least one light zone (this is a convention, because it depends // on the background - but we can argue that "no background" corresponds to no reflection (then dark), and, say, a ping pong ball or finger is front // will be "light". // Mmm... not convinced by the arguments above. Let's rather do this: lightTouched will mean ALWAYS that the saccade is touched by something, meaning it's intensity // goes from dark to light, i.e. at least one light AND one dark zone. In fact we should have THREE states: touched, all light, all dark. if (modeThreshold==FIXED) { lightTouched=isLightZone; lightZone=isLightZone; darkZone=isDarkZone; if (lightTouched) lightState=TOUCHED; else if (isLightZone) lightState=ALL_LIGHT; else lightState=ALL_DARK; } else { lightTouched=(isLightZone&&isDarkZone); // assuming only two modes for modeThreshold lightZone=isLightZone; darkZone=isDarkZone; if (lightTouched) lightState=TOUCHED; else if (isLightZone) lightState=ALL_LIGHT; else lightState=ALL_DARK; } // Return lightTouched for commodity: //return(lightTouched); return(lightState); }