Aegisub/aegisub/src/audio_provider_dummy.cpp

// Copyright (c) 2005-2006, Rodrigo Braz Monteiro, Fredrik Mellbin
// All rights reserved.
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// Aegisub Project http://www.aegisub.org/
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// $Id$

/// @file audio_provider_dummy.cpp
/// @brief Dummy (silence or noise) audio provider
/// @ingroup audio_input
///

#include "config.h"

#include "audio_provider_dummy.h"
#include "utils.h"


/// @brief Constructor 
/// @param dur_ms 
/// @param _noise 
///
DummyAudioProvider::DummyAudioProvider(unsigned long dur_ms, bool _noise) {
	noise = _noise;
	channels = 1;
	sample_rate = 44100;
	bytes_per_sample = 2;
	num_samples = (int64_t)dur_ms * sample_rate / 1000;
}

/// @brief Destructor 
///
DummyAudioProvider::~DummyAudioProvider() {
}

/// @brief Get audio 
/// @param buf   
/// @param start 
/// @param count 
///
void DummyAudioProvider::GetAudio(void *buf, int64_t start, int64_t count) {
	short *workbuf = (short*)buf;

	if (noise) {
		while (--count > 0)
			*workbuf++ = (rand() - RAND_MAX/2) * 10000 / RAND_MAX;
	}
	else {
		while (--count > 0)
			*workbuf++ = 0;
	}
}