多媒体

cmakelist 添加Multimedia模块

设备信息查询

#include <QAudioDevice>
#include <QCameraDevice>
#include <QCameraFormat>
#include <QMediaDevices>void showDevs()
{QList<QAudioDevice> inAudios = QMediaDevices::audioInputs(); // 获取音频输入设备列表QList<QAudioDevice> outAudios = QMediaDevices::audioOutputs(); // 输出设备QList<QCameraDevice> cameras = QMediaDevices::videoInputs(); // 获取视频输入设备for (auto& ia : inAudios) {qInfo() << "设备名称:" << ia.description(); // 设备描述qInfo() << "设备Id:" << ia.id();qInfo() << "最大声道数:" << ia.maximumChannelCount(); // 最大声道数qInfo() << "最大采样率:" << ia.maximumSampleRate(); // 最大采样率QAudioFormat fmt = ia.preferredFormat();qInfo() << "=====默认设备参数====";qInfo() << "声道数" << fmt.channelCount();qInfo() << "声道配置" << fmt.channelConfig();qInfo() << "采样率" << fmt.sampleRate();qInfo() << "采样格式" << fmt.sampleFormat();}for (auto& ia : outAudios) {qInfo() << "设备名称:" << ia.description(); // 设备描述qInfo() << "设备Id:" << ia.id();qInfo() << "最大声道数:" << ia.maximumChannelCount(); // 最大声道数qInfo() << "最大采样率:" << ia.maximumSampleRate(); // 最大采样率QAudioFormat fmt = ia.preferredFormat();qInfo() << "=====默认设备参数====";qInfo() << "声道数" << fmt.channelCount();qInfo() << "声道配置" << fmt.channelConfig();qInfo() << "采样率" << fmt.sampleRate();qInfo() << "采样格式" << fmt.sampleFormat();}for (auto& cd : cameras) {qInfo() << "设备名称:" << cd.description(); // 设备描述qInfo() << "设备Id:" << cd.id();qInfo() << "设备方位" << cd.position();QList<QCameraFormat> fmt = cd.videoFormats();for (auto& f : fmt) {qInfo() << "最大帧率" << f.maxFrameRate();qInfo() << "最小帧率" << f.minFrameRate();qInfo() << "像素格式" << f.pixelFormat();}}
}

音频

cmakelist 添加MultimediaWidgets模块

播放音频

播放mp3、aac等非原始格式音频

void playAudio()
{QMediaPlayer* player = new QMediaPlayer;player->setSource(QUrl::fromLocalFile("E:/KwDownload/song/陈占美-恰似你的温柔.mp3"));QAudioOutput* adOut = new QAudioOutput;adOut->setVolume(0.8); // 设置音量，0到1之间player->setAudioOutput(adOut);player->play();
}

播放原始音频pcm格式

void playAudio2()
{QFile file("G:/qtproject/multiMedia/audio.pcm");file.open(QFile::ReadOnly);QAudioDevice dev = QMediaDevices::defaultAudioOutput();QAudioFormat fmt = dev.preferredFormat();QAudioSink* sink = new QAudioSink(dev, fmt);QIODevice* iodev = sink->start();while (true) {if (sink->bytesFree() > 85535)iodev->write(file.read(80000));}sink->start(iodev);
}

录制音频

存储位置只能是本地文件系统位置，存储格式也是固定的

void Widget::recordAudio()
{cs = new QMediaCaptureSession;// 输入设备audIn = new QAudioInput;audIn->setVolume(0.8);// 录制器recorder = new QMediaRecorder;cs->setAudioInput(audIn);cs->setRecorder(recorder);recorder->setQuality(QMediaRecorder::HighQuality);recorder->setOutputLocation(QUrl::fromLocalFile("C:/Users/PVer/Desktop/test")); // 设置存储路径
}void Widget::on_pushButton_clicked()
{static bool state = true;if (state) {ui->pushButton->setText("结束录制");recorder->record();} else {ui->pushButton->setText("开始录制");recorder->stop();}state = !state;
}

低延迟音效

void testSoundEffect()
{QSoundEffect* ef = new QSoundEffect(QMediaDevices::defaultAudioOutput());ef->setSource(QUrl::fromLocalFile("../../currency.wav")); // 设置文件路径ef->setVolume(1);ef->setLoopCount(2);ef->play();
}

低级音频播放和录制

void recordAudio()
{QAudioFormat fmt;fmt.setChannelCount(2);fmt.setSampleFormat(QAudioFormat::Float);fmt.setSampleRate(44100);if (!QMediaDevices::defaultAudioInput().isFormatSupported(fmt)) {qCritical() << "不支持该格式";return;}QAudioSource* as = new QAudioSource(QMediaDevices::defaultAudioInput(), fmt);QFile* file = new QFile("../../test.pcm");if (!file->open(QFile::ReadWrite)) {qCritical() << "文件打开失败";return;}as->start(file);// 设置定时结束录制，否则原始音频太大QTimer::singleShot(3000, [=] { as->stop(); });
}

推送和拉取

通过QAudiSink类从QIODevice中拉去数据
相反数据可以写入QIODevice

解码压缩音频到内存

与音频处理相关的类

视频

播放视频

void playVideo()
{QMediaPlayer* player = new QMediaPlayer;player->setSource(QUrl::fromLocalFile("../../黑神话.mp4"));// 设置画面输出设备QVideoWidget* vw = new QVideoWidget;player->setVideoOutput(vw);vw->show();// 设置声音输出设备QAudioOutput* audio = new QAudioOutput;player->setAudioOutput(audio);// 开始播放player->play();
}

处理低级视频帧

录制视频

void Widget::recordVideo()
{cs2 = new QMediaCaptureSession;recorder2 = new QMediaRecorder;camera = new QCamera(QMediaDevices::defaultVideoInput());if (!camera->isAvailable()) {qInfo() << "没有可用摄像头";return;}QVideoWidget* vw = new QVideoWidget;cs2->setAudioInput(audIn);cs2->setRecorder(recorder2);cs2->setVideoOutput(vw);recorder2->setQuality(QMediaRecorder::HighQuality);recorder2->setOutputLocation(QUrl::fromLocalFile("C:/Users/PVer/Desktop/vediotest"));vw->show(); // 显示视频窗口camera->setActive(true); // 激活相机
}
//按钮的信号与槽连接
void Widget::on_pushButton_2_clicked()
{static bool state = true;if (state) {ui->pushButton_2->setText("结束录制");recorder2->record();} else {ui->pushButton_2->setText("开始录制");recorder2->stop();}state = !state;
}

与视频处理相关的类

支持的媒体格式