c++ - 分别更改左右声道音量 waveOut SetVolume C++

Question

实际上我想将音频设备的左声道和右声道的音量控制给用户，用户为每个声道使用不同的数字。我使用了“waveOutSetVolume()”。它有 2 个参数。第一个是句柄，第二个是十六进制或 DWORD 数字。

我有 2 个数字。每个 channel 一个，然后将它们转换为字符串。现在如何将它们转换为“0x”格式的十六进制？一般如何分别改变每个 channel 的音量？

void Audio::setChannelsVolume(int rightChannelVolume, int leftChannelVolume)
{
if(leftChannelVolume < 0)
    leftChannelVolume = 0;

if(leftChannelVolume > 100)
    leftChannelVolume = 100;

if(rightChannelVolume < 0)
    rightChannelVolume = 0;

if(rightChannelVolume > 100)
    rightChannelVolume = 100;

stringstream volume;

if(leftChannelVolume < 7 && leftChannelVolume > 0)
    volume << "0x0" << std::hex << soundVolumeCalculus(leftChannelVolume);
else
    volume << "0x"<< std::hex << soundVolumeCalculus(leftChannelVolume);

if(rightChannelVolume < 7 && rightChannelVolume > 0)
    volume << "0" << std::hex << soundVolumeCalculus(rightChannelVolume);
else
    volume << std::hex << soundVolumeCalculus(rightChannelVolume);

string str = volume.str();
cout<<str;
const char* ch = str.c_str();
waveOutSetVolume(hWaveOut,(DWORD)ch);
}

////////////////////////////////////////////

int Audio::soundVolumeCalculus(int volume)
{
return (int)((65535*volume)/100);
}

Answer 1

我解决了

DWORD d = 0xffff & soundVolumeCalculus(leftChannelVolume) ;
DWORD dd = 0xffff0000 & (soundVolumeCalculus(rightChannelVolume)*65535);

waveOutSetVolume(hWaveOut,dd+d);