Hey guys,
I have a question about the Peak function from the audio library,
I am attaching the code here for reference :

This is analyse_peak.h :

Code:
#ifndef analyze_peakdetect_h_
#define analyze_peakdetect_h_

#include "Arduino.h"
#include "AudioStream.h"

class AudioAnalyzePeak : public AudioStream
{
public:
	AudioAnalyzePeak(void) : AudioStream(1, inputQueueArray) {
		min_sample = 32767;
		max_sample = -32768;
	}
	bool available(void) {
		__disable_irq();
		bool flag = new_output;
		if (flag) new_output = false;
		__enable_irq();
		return flag;
	}
	float read(void) {
		__disable_irq();
		int min = min_sample;
		int max = max_sample;
		min_sample = 32767;
		max_sample = -32768;
		__enable_irq();
		min = abs(min);
		max = abs(max);
		if (min > max) max = min;
		return (float)max / 32767.0f;
	}
	float readPeakToPeak(void) {
		__disable_irq();
		int min = min_sample;
		int max = max_sample;
		min_sample = 32767;
		max_sample = -32768;
		__enable_irq();
		return (float)(max - min) / 32767.0f;
	}

	virtual void update(void);
private:
	audio_block_t *inputQueueArray[1];
	volatile bool new_output;
	int16_t min_sample;
	int16_t max_sample;
};

#endif
and this is analyse_peak.cpp :

Code:
#include "analyze_peak.h"

void AudioAnalyzePeak::update(void)
{
	audio_block_t *block;
	const int16_t *p, *end;
	int32_t min, max;

	block = receiveReadOnly();
	if (!block) {
		return;
	}
	p = block->data;
	end = p + AUDIO_BLOCK_SAMPLES;
	min = min_sample;
	max = max_sample;
	do {
		int16_t d=*p++;
		// TODO: can we speed this up with SSUB16 and SEL
		// http://www.m4-unleashed.com/parallel-comparison/
		if (d<min) min=d;
		if (d>max) max=d;
	} while (p < end);
	min_sample = min;
	max_sample = max;
	new_output = true;
	release(block);
}
My question is this : How is it possible for min_sample and max_sample to ever be updated ?
As one can see they are both initialized in the constructor to

Code:
min_sample = 32767;
max_sample = -32768;
and the update function only updates them if they achieve greater or smaller values which seems impossible...
what am I missing here ?

thanks in advance, A.H.