audio_play_thread.cpp

视频会议源码

///////////////////////////////////////////////////////
// FileName:	audio_play_thread.cpp
// Author:		b1gm0use
// Project:		myaudio

#include <iostream>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/soundcard.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <qsemaphore.h>

#include "audio_play_thread.h"
#include "audio_player.h"
#include "audio.h"
#include "common.h"
#include "network.h"
#include "avi.h"

using namespace std;

///////////////////////////////////////////////////////
// Public Functions
///////////////////////////////////////////////////////

// 构造函数
// 传入参数为
// ap_in 上层AudioPlayer对象指针
// img 图像参数
// msg_in 为一个字符串类型的参数，用于传递IP或设备名
// type_in AudioPlayer类型
// stackSize QThread所用的参数
audio_play_thread::audio_play_thread ( avi * avi_ptr_in, 
		AudioPlayer * ap_in, unsigned int stackSize )
		:QThread( stackSize ) // {{{
{
	verbose_output( 2, "create audio_play_thread." );

	ap = ap_in;

	fd_w = 0;

	frame = 0;

	avi_ptr = avi_ptr_in;

} // }}}

void audio_play_thread::init( void ) // {{{
{
	
	verbose_output( 2, "init audio_play_thread." );

	int arg = 0;
	int status = 0;


	// 打开回放
	fd_w = open( avi_ptr->audio_dev, O_WRONLY);

	if (fd_w < 0) 
	{
		cerr << "open device [" << avi_ptr->audio_dev << "] failed." << endl;
		::exit(1);
	}

	// 设置采样时的量化位数 
	arg = SIZE;

	status = ioctl(fd_w, SOUND_PCM_WRITE_BITS, &arg);

	if (status == -1)
	{
		cerr << "SOUND_PCM_WRITE_BITS ioctl failed" << endl;;
		::exit( 1 );
	}

	if (arg != SIZE)
	{
		cerr << "Warning! unable to set sample size" << endl;;
	}

	verbose_output( 2, "use sample size: ", arg );

	// 设置采样时的声道数目 
	arg = CHANNELS; 

	status = ioctl(fd_w, SOUND_PCM_WRITE_CHANNELS, &arg);

	if (status == -1)
	{
		cerr << "SOUND_PCM_WRITE_CHANNELS ioctl failed" << endl;;
		::exit( 1 );
	}

	if (arg != CHANNELS)
	{
		cerr << "Warning! unable to set number of channels" << endl;;
	}

	verbose_output( 2, "use audio channels: ", arg );


	// 设置采样时的采样频率 
	arg = RATE;

	status = ioctl(fd_w, SOUND_PCM_WRITE_RATE, &arg);

	if (status == -1)
	{
		cerr << "SOUND_PCM_WRITE_WRITE ioctl failed" << endl;;
		::exit( 1 );
	}

	if (arg != RATE )
	{
		cerr << "Warning! unable to set sample rate" << endl;;
	}
	
	verbose_output( 2, "use sample rate: ", arg );

} // }}}

// 运行部分，线程代码在这里
void audio_play_thread::run ( void ) // {{{
{
	int status = 0;
	
	verbose_output( 2, "audio_play_thread begin running." );

	//(*(avi_ptr->audio_can_play_semaphore))++;


	while ( 1 )
	{	

		ap->ready_to_play_audio->wait();

		verbose_output( 4, "Playing...lock frame No.", frame );

		(*(avi_ptr->snd_buff_semaphore[frame]))++;
		//回放

		status = write( fd_w, avi_ptr->snd_buff[frame], BUFF_SIZE * LENGTH );

		if ( status == -1 )
		{
			cerr << "Write to device error." << endl;
			::exit( 1 );
		}

		verbose_output( 4, "Playing...unlock frame No.", frame );
		(*(avi_ptr->snd_buff_semaphore[frame]))--;

		// 等待回放结束

		//status = ioctl( fd_w, SOUND_PCM_SYNC, 0 ); 
		
		if ( status == -1 )
		{
			  cerr << "SOUND_PCM_SYNC ioctl failed" << endl;
			  ::exit( 1 );
		}

		frame++;

		frame %= 3;

	}

	return;
	
} // }}}