SFML 音频不播放

Question

我有这个代码：

#include <SFML/Audio.hpp>
#include <unistd.h>
#include <cmath>

int main()
{
    const double volume = 10000;
    const sf::Uint64 sampleCount = 44100;
    sf::Int16* samples = new sf::Int16[sampleCount];
    for (sf::Uint64 i = 0; i < sampleCount; i++) {
        samples[sampleCount] = sin(((double)i / 44100.0)*M_PI*2.0*440) * volume;
    }

    sf::SoundBuffer b;
    b.loadFromSamples(samples, sampleCount, 1, 44100);

    sf::Sound s;
    s.setBuffer(b);
    s.play();

    usleep(1000000);

    delete [] samples;

    return 0;
}

然后我编译：

g++ -o sound main.cpp -framework SFML -framework sfml-audio -F/Library/Frameworks

它应该播放 440 Hz 的正弦波 1 秒，但它没有播放任何东西，只是等待一秒。

Answer 1

你的循环通过写入你不拥有的内存来调用未定义的行为，特别是 samples[sampleCount]。我最好的猜测是它播放全零或随机静态，但这取决于您的编译器来弄清楚它究竟是如何失败的。

这个：

sf::Int16* samples = new sf::Int16[sampleCount];
for (sf::Uint64 i = 0; i < sampleCount; i++) {
    samples[sampleCount] = sin(((double)i / 44100.0)*M_PI*2.0*440) * volume;
}

需要

sf::Int16* samples = new sf::Int16[sampleCount];
for (sf::Uint64 i = 0; i < sampleCount; i++) {
    samples[i] = sin(((double)i / 44100.0)*M_PI*2.0*440) * volume;
}

SFML 音频不播放

SFML Audio not playing

c++

sfml