view Source/TouchKeys/KeyIdleDetector.cpp @ 20:dfff66c07936

Lots of minor changes to support building on Visual Studio. A few MSVC-specific #ifdefs to eliminate things Visual Studio doesn't like. This version now compiles on Windows (provided liblo, Juce and pthread are present) but the TouchKeys device support is not yet enabled. Also, the code now needs to be re-checked on Mac and Linux.

/*
  TouchKeys: multi-touch musical keyboard control software
  Copyright (c) 2013 Andrew McPherson

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
 
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
  =====================================================================
 
  KeyIdleDetector.cpp: uses continuous key position to detect whether a key
  is idle or active; active keys will have more detailed tracking applied
  to their position, so detecting idle keys saves processing.
*/

#include "KeyIdleDetector.h"

// Default constructor
KeyIdleDetector::KeyIdleDetector(capacity_type capacity, Node<key_position>& keyBuffer, key_position positionThreshold, 
								 key_position activityThreshold, int counterThreshold)
: Node<int>(capacity), keyBuffer_(keyBuffer), accumulator_(kKeyIdleNumSamples+1, keyBuffer),
  keyIdleThreshold_(kDefaultKeyIdleThreshold), activityThreshold_(activityThreshold), positionThreshold_(positionThreshold),
  numberOfFramesWithoutActivity_(0), noActivityCounterThreshold_(counterThreshold),
  idleState_(kIdleDetectorUnknown)
{
	// Register to receive messages from the accumulator each time it gets a new sample
	  //std::cout << "Registering IdleDetector\n";
	  
	  registerForTrigger(&accumulator_);
	  
	//  std::cout << "IdleDetector: this_source = " << (TriggerSource*)this << " this_dest = " << (TriggerDestination*)this << " accumulator = " << &accumulator_ << std::endl;
}

// Copy constructor
/*KeyIdleDetector::KeyIdleDetector(KeyIdleDetector const& obj)
  : Node<int>(obj), keyBuffer_(obj.keyBuffer_), accumulator_(obj.accumulator_), idleState_(obj.idleState_), 
    activityThreshold_(obj.activityThreshold_), positionThreshold_(obj.positionThreshold_),
    numberOfFramesWithoutActivity_(obj.numberOfFramesWithoutActivity_),
    keyIdleThreshold_(obj.keyIdleThreshold_), noActivityCounterThreshold_(obj.noActivityCounterThreshold_) {
	registerForTrigger(&accumulator_);
}*/

// Clear current state and reset to unknown idle state.
void KeyIdleDetector::clear() {
	Node<int>::clear();
	idleState_ = kIdleDetectorUnknown;
	numberOfFramesWithoutActivity_ = 0;
}

// Evaluator function.  Find the maximum deviation from average of the key motion.

void KeyIdleDetector::triggerReceived(TriggerSource* who, timestamp_type timestamp) {
	//std::cout << "KeyIdleDetector::triggerReceived\n";

	if(who != &accumulator_)
		return;

    key_position currentKeyPosition = keyBuffer_.latest();
    std::pair<int, key_position> currentAccumulator = accumulator_.latest();
    
    // Check that we have enough samples
    if(currentAccumulator.first < kKeyIdleNumSamples)
        return;
    
    // Behavior depends on whether we were idle or not before (or in unknown state)
    if(idleState_ == kIdleDetectorIdle) {
        // If idle right now, don't do anything if the key position is below a threshold
        if(currentKeyPosition < keyIdleThreshold_)
            return;

        // If average is below a second, slightly higher threshold, stay idle
        key_position averageValue = currentAccumulator.second / (key_position)currentAccumulator.first;
        if(averageValue < keyIdleThreshold_ * 2)
            return;
        
        // Go active, notifying any listeners
        idleState_ = kIdleDetectorActive;
        insert(kIdleDetectorActive, timestamp);
    }
    else { // Active or unknown
        // Rule out any cases that would immediately take the key active
        key_position averageValue = currentAccumulator.second / (key_position)currentAccumulator.first;
        if(averageValue >= keyIdleThreshold_ * 2) {
            numberOfFramesWithoutActivity_ = 0;
            return;
        }
        
#if 0
        key_position maxDeviation = 0;
        size_type endIndex = keyBuffer_.endIndex();
        // Find and return the maximum deviation from the average
        for(int i = endIndex - kKeyIdleNumSamples; i < endIndex; i++) {
            key_position diff = key_abs(keyBuffer_[i] - averageValue);
            if(diff > maxDeviation)
                maxDeviation = diff;
        }
#endif
        key_position averageDeviation = 0;
        size_type endIndex = keyBuffer_.endIndex();
        // Find and return the average deviation from mean
        for(int i = endIndex - kKeyIdleNumSamples; i < endIndex; i++) {
            averageDeviation += key_abs(keyBuffer_[i] - averageValue);
        }
        averageDeviation /= kKeyIdleNumSamples;
        
        //std::cout << "averageDeviation = " << averageDeviation << " counter = " << numberOfFramesWithoutActivity_ << std::endl;
        
        if(averageDeviation < activityThreshold_) {
            // Key registers as "flat".  Check if it has stayed that way for long enough, and with a position close enough
            // to resting position, to change the state back to Idle.
            
            numberOfFramesWithoutActivity_++;
            if(numberOfFramesWithoutActivity_ >= noActivityCounterThreshold_) {
                idleState_ = kIdleDetectorIdle;
                insert(kIdleDetectorIdle, timestamp);
            }
        }
        else
            numberOfFramesWithoutActivity_ = 0;
    }

#if 0 /* Old idle detection */
	
	//std::cout << "KeyIdleDetector::triggerReceived2\n";
	
	std::pair<int, key_position> current = accumulator_.latest();
	
	if(current.first < kKeyIdleNumSamples)
		return;

	// Find the average value
	key_position averageValue = current.second / (key_position)current.first;
	key_position maxDeviation = 0;
	
	size_type endIndex = keyBuffer_.endIndex();
	// Find and return the maximum deviation from the average
	for(int i = endIndex - kKeyIdleNumSamples; i < endIndex; i++) {
		key_position diff = key_abs(keyBuffer_[i] - averageValue);
		if(diff > maxDeviation)
			maxDeviation = diff;
	}
	
	// TODO: If we get here, good enough to go to initial activity.  But need to search back to determine start point.
	// Also need to update current start values (see kblisten code).
	
	// Insert a new sample (and hence send a trigger) whenever the maximum deviation crosses the threshold.
	
	if((maxDeviation >= activityThreshold_ || keyBuffer_.latest() >= positionThreshold_) && idleState_ != kIdleDetectorActive) {
		idleState_ = kIdleDetectorActive;
		numberOfFramesWithoutActivity_ = 0;
		insert(kIdleDetectorActive, timestamp);
		//std::cout << "deviation = " << maxDeviation << " average = " << averageValue << std::endl;
	}
	else if(maxDeviation < activityThreshold_ && idleState_ != kIdleDetectorIdle) {
		// Key registers as "flat".  Check if it has stayed that way for long enough, and with a position close enough
		// to resting position, to change the state back to Idle.
		
		numberOfFramesWithoutActivity_++;
		if(numberOfFramesWithoutActivity_ >= noActivityCounterThreshold_ && keyBuffer_.latest() < positionThreshold_) {
			idleState_ = kIdleDetectorIdle;
			insert(kIdleDetectorIdle, timestamp);
			//std::cout << "deviation = " << maxDeviation << " average = " << averageValue << std::endl;
			/*Accumulator<key_position,kKeyIdleNumSamples>::iterator it;
			
			for(it = accumulator_.begin(); it != accumulator_.end(); it++) {
				std::cout << it->first << " " << it->second << std::endl;
			}*/
		}
	}
#endif
}