QT5 operating camera error in ubuntu environment: cannot find -lpulse-mainloop-glib cannot find -lpulse cannot find -lglib-2.0

Both QT and Opencv can operate the camera. I used QT5 to operate the camera in the ubuntu environment and found the following error:

Normally, QT does not require additional libraries to operate the camera. Why can't these libraries be found? Then I checked /usr/lib/x86_64-linux-gnu and found libraries with similar names.

But there is no library named libpulse-mainloop-glib.so libpulse.so libglib-2.0.so, so I thought it was because the library name was wrong, so I created the following soft connection:

sudo ln -s /usr/lib/x86_64-linux-gnu/libpulse-mainloop-glib.so.0.0.5 /usr/lib/x86_64-linux-gnu/libpulse-mainloop-glib.so
sudo ln -s /usr /lib/x86_64-linux-gnu/libpulse-simple.so.0.1.1 /usr/lib/x86_64-linux-gnu/libpulse.so
sudo ln -s /usr/lib/x86_64-linux-gnu/libglib-2.0 .so.0.5600.4 /usr/lib/x86_64-linux-gnu/libglib-2.0.so

After creation, I found that the compilation was normal:

Table of contents

1.Code

2. Operational effect

---

1.Code

main.cpp

#include <QApplication>
#include <QDebug>
#include <QCamera>
#include <QCameraViewfinder>
#include <QCameraImageCapture>
#include <QImage>
#include <QPixmap>
#include <QVBoxLayout>
#include <QPushButton>
#include <QLabel>

int main(int argc, char *argv[]) {

    QApplication a(argc, argv);

    //a.setStyleSheet("QCameraViewfinder, QLabel { border: 2px dashed grey;}");
    a.setStyleSheet("QPushButton { color: red; background-color: blue }");
    // 摄像头对象
    QCamera *camera = new QCamera();
    // 用于实时显示摄像头图像
    QCameraViewfinder *viewfinder = new QCameraViewfinder();
    // 用于截取摄像头图像
    QCameraImageCapture *imageCapture = new QCameraImageCapture(camera);
    // camera 使用 viewfinder 实时显示图像
    camera->setViewfinder(viewfinder);
    // 使 viewfinder 能够使用 QSS
    viewfinder->setAttribute(Qt::WA_StyledBackground, true);
    // 拍照预览的 label
    QLabel *previewLabel = new QLabel("");
    // 点击拍照的按钮
    QPushButton *captureButton = new QPushButton("拍照");
    viewfinder->setFixedHeight(300);
    previewLabel->setFixedHeight(300);
    previewLabel->setMinimumWidth(300);
    previewLabel->setAlignment(Qt::AlignCenter);

    // 布局 widgets
    QVBoxLayout *layout = new QVBoxLayout();
    layout->addWidget(viewfinder);
    layout->addWidget(previewLabel);
    layout->addWidget(captureButton);
    layout->addStretch();

    QWidget *window = new QWidget();
    window->setLayout(layout);
    window->show();
    camera->start();

    // 点击拍照
    QObject::connect(captureButton, &QPushButton::clicked, [=] {
        imageCapture->capture("capture.jpg"); // 如果不传入截图文件的路径，则会使用默认的路径，每次截图生成一个图片
    });

    // 拍照完成后的槽函数，可以把 image 保存到自己想要的位置
    QObject::connect(imageCapture, &QCameraImageCapture::imageCaptured, [=](int id, const QImage &image) {
        Q_UNUSED(id)
        QImage scaledImage = image.scaled(previewLabel->size(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
        previewLabel->setPixmap(QPixmap::fromImage(scaledImage));
    });

    return a.exec();

}

use_camera.pro

#-------------------------------------------------
#
# Project created by QtCreator 2023-09-04T00:18:55
#
#-------------------------------------------------

QT       += core gui
QT += multimedia multimediawidgets

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets


TARGET = use_camera
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += \
        main.cpp

2. Operational effect