Aegisub/core/audio_player_portaudio.cpp

// Copyright (c) 2005, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//   * Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//   * Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//   * Neither the name of the Aegisub Group nor the names of its contributors
//     may be used to endorse or promote products derived from this software
//     without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//


///////////
// Headers
#include "audio_player_portaudio.h"
#include "audio_provider.h"
#include "utils.h"


/////////////////////
// Reference counter
int PortAudioPlayer::pa_refcount = 0;


///////////////
// Constructor
PortAudioPlayer::PortAudioPlayer() {
	// Initialize portaudio
	if (!pa_refcount) {
		PaError err = Pa_Initialize();
		if (err != paNoError) {
			static wchar_t errormsg[2048];
			swprintf(errormsg, 2048, L"Failed opening PortAudio: %s", Pa_GetErrorText(err));
			throw (const wchar_t *)errormsg;
		}
		pa_refcount++;
	}

	// Variables
	playing = false;
	stopping = false;
	volume = 1.0f;
	paStart = 0.0;
}


//////////////
// Destructor
PortAudioPlayer::~PortAudioPlayer() {
	// Deinit portaudio
	if (!--pa_refcount) Pa_Terminate();
}

#ifdef __WINDOWS__
typedef unsigned __int64 uint64_t;
#endif

//////////////////////
// PortAudio callback
int PortAudioPlayer::paCallback(void *inputBuffer, void *outputBuffer, unsigned long framesPerBuffer, PaTimestamp outTime, void *userData) {
	// Get provider
	PortAudioPlayer *player = (PortAudioPlayer *) userData;
	AudioProvider *provider = player->GetProvider();
	int end = 0;

	// Calculate how much left
	__int64 lenAvailable = player->endPos - player->playPos;
	uint64_t avail = 0;
	if (lenAvailable > 0) {
		avail = lenAvailable;
		if (avail > framesPerBuffer) {
			lenAvailable = framesPerBuffer;
			avail = lenAvailable;
		}
	}
	else {
		lenAvailable = 0;
		avail = 0;
	}

	// Play something
	if (lenAvailable > 0) {
		provider->GetAudio(outputBuffer,player->playPos,lenAvailable);
	}

	// Pad end with blank
	if (avail < (uint64_t) framesPerBuffer) {
		//provider->softStop = true;
	}

	// Set volume
	short *output = (short*) outputBuffer;
	for (unsigned int i=0;i<avail;i++) output[i] = MID(-(1<<15),int(output[i] * player->GetVolume()),(1<<15)-1);

	// Fill rest with blank
	for (unsigned int i=avail;i<framesPerBuffer;i++) output[i]=0;

	// Set play position (and real one)
	player->playPos += framesPerBuffer;
#ifndef __APPLE__
	player->realPlayPos = (__int64)(Pa_StreamTime(player->stream) - player->paStart) + player->startPos;
#else
	// AudioDeviceGetCurrentTime(), used by Pa_StreamTime() on OS X, is buggered, so use playPos for now
	player->realPlayPos = player->playPos;
#endif
	
	// Cap to start if lower
	return end;
}


////////
// Play
void PortAudioPlayer::Play(__int64 start,__int64 count) {
	// Stop if it's already playing
	wxMutexLocker locker(PAMutex);

	// Set values
	endPos = start + count;
	playPos = start;
	realPlayPos = start;
	startPos = start;

	// Start playing
	if (!playing) {
		PaError err = Pa_StartStream(stream);
		if (err != paNoError) {
			return;
		}
	}
	playing = true;
	paStart = Pa_StreamTime(stream);

	// Update timer
	if (displayTimer && !displayTimer->IsRunning()) displayTimer->Start(15);
}


////////
// Stop
void PortAudioPlayer::Stop(bool timerToo) {
	//wxMutexLocker locker(PAMutex);
	//softStop = false;

	// Stop stream
	playing = false;
	Pa_StopStream (stream);

	// Stop timer
	if (timerToo && displayTimer) {
		displayTimer->Stop();
	}
}


///////////////
// Open stream
void PortAudioPlayer::OpenStream() {
	// Open stream
	PaError err = Pa_OpenDefaultStream(&stream,0,provider->GetChannels(),paInt16,provider->GetSampleRate(),256,16,paCallback,this);
	if (err != paNoError) {
		throw wxString(_T("Failed initializing PortAudio stream with error: ") + wxString(Pa_GetErrorText(err),wxConvLocal));
	}
}


///////////////
// Close stream
void PortAudioPlayer::CloseStream() {
	try {
		Stop(false);
		Pa_CloseStream(stream);
	} catch (...) {}
}