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原博主博客地址:https://blog.csdn.net/qq21497936
原博主博客導航:https://blog.csdn.net/qq21497936/article/details/102478062
本文章博客地址:https://blog.csdn.net/qq21497936/article/details/102993007
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紅胖子(紅模仿)的博文大全:開發技術集合(包含Qt實用技術、樹莓派、三維、OpenCV、OpenGL、ffmpeg、OSG、單片機、軟硬結合等等)持續更新中...(點擊傳送門)
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OpenCV開發專欄(點擊傳送門)
需求
使用OpenCV做功能,播放攝像頭(usb和網絡),對攝像頭設備進行參數調整(亮度、對比度、飽和度、色調、增益、曝光度)調節,拍照和錄像。
原理
使用OpenCV打開攝像頭(可打開USB和網路哦攝像頭),渲染圖像顯示,可使用OpenCV屬性調整攝像頭的各項參數,使用拍照可以將當前圖片拍照,使用錄像可以從當前時間點開始錄像直至停止錄像。
注意
目前測試,即使PC上有編碼器,但是OpenCV存儲mat爲對應的錄像視頻文件失敗,出現:
- 錄製完視頻大小爲200多B(基本爲0),mp4格式時(查看入坑一)
- 錄製完視頻大小爲6KB,avi格式時
- 錄製avi傳入圖像mat,源碼內部出現錯誤宕機
相關博客
《OpenCV開發筆記(四):OpenCV圖片和視頻數據的讀取與存儲》
《OpenCV開發筆記(五):OpenCV讀取與操作攝像頭》
《Qt實用技巧:使用OpenCV庫操作攝像頭拍照、調節參數和視頻錄製》
《Qt實用技巧:使用OpenCV庫的視頻播放器(支持播放器操作,如暫停、恢復、停止、時間、進度條拽託等)》
《Qt實用技巧:使用QMediaPlayer播放mp4文件》
《Qt實用技巧:使用QMediaPlayer和Windows自帶組件播放swf、rmvb、mpg、mp4等視頻文件》
Demo:cameraTool v1.0.0
運行效果
下載地址
CSDN地址:https://download.csdn.net/download/qq21497936/11968135
核心代碼
打開攝像頭代碼
bool OpenCVManager::startCapture(int usb, int width, int height)
{
if(!_pVideoCapture->open(usb))
{
qDebug() << __FILE__ << __LINE__ << "Failed to start capture :" << usb;
return false;
}
_width = width;
_height = height;
_pVideoCapture->set(CV_CAP_PROP_FRAME_WIDTH, _width);
_pVideoCapture->set(CV_CAP_PROP_FRAME_HEIGHT, _height);
_width = _pVideoCapture->get(CV_CAP_PROP_FRAME_WIDTH);
_height = _pVideoCapture->get(CV_CAP_PROP_FRAME_HEIGHT);
_pVideoCapture->set(CV_CAP_PROP_FPS, 25);
_brightness = _pVideoCapture->get(cv::CAP_PROP_BRIGHTNESS);
_contrast = _pVideoCapture->get(cv::CAP_PROP_CONTRAST);
_saturation = _pVideoCapture->get(cv::CAP_PROP_SATURATION);
_hue = _pVideoCapture->get(cv::CAP_PROP_HUE);
_gain = _pVideoCapture->get(cv::CAP_PROP_GAIN);
_exposure = _pVideoCapture->get(cv::CAP_PROP_EXPOSURE);
QTimer::singleShot(0, this, SLOT(slot_captrueFrame()));
return true;
}
調整屬性代碼
bool OpenCVManager::getShowProperty() const
{
return _showProperty;
}
void OpenCVManager::setShowProperty(bool value)
{
_showProperty = value;
}
double OpenCVManager::getBrightness()
{
return _brightness;
}
void OpenCVManager::setBrightness(double value)
{
_brightness = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_BRIGHTNESS, _brightness);
}
}
double OpenCVManager::getContrast() const
{
return _contrast;
}
void OpenCVManager::setContrast(double value)
{
_contrast = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_CONTRAST, _contrast);
}
}
double OpenCVManager::getSaturation() const
{
return _saturation;
}
void OpenCVManager::setSaturation(double value)
{
_saturation = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_SATURATION, _saturation);
}
}
double OpenCVManager::getHue() const
{
return _hue;
}
void OpenCVManager::setHue(double value)
{
_hue = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_HUE, _hue);
}
}
double OpenCVManager::getGain() const
{
return _gain;
}
void OpenCVManager::setGain(double value)
{
_gain = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_GAIN, _gain);
}
}
double OpenCVManager::getExposure() const
{
return _exposure;
}
void OpenCVManager::setExposure(double value)
{
_exposure = value;
if(_pVideoCapture)
{
_pVideoCapture->set(cv::CAP_PROP_EXPOSURE, _exposure);
}
}
拍照代碼
void PhotoAndRecordWidget::on_pushButton_photo_clicked()
{
QString timeStr = QDateTime::currentDateTime().toString("yyyy-MM-hh hh_mm_ss");
QString dirName = "photos";
if(!QFile::exists(dirName))
{
QDir dir;
if(!dir.mkdir(dirName))
{
ui->label_state->setText("創建文件夾 " + dirName + "失敗!!!");
}
}
QString filePath = QString("%1/%2.png").arg(dirName).arg(timeStr);
if(_image.save(filePath))
{
ui->label_state->setText("保存照片至: " + filePath);
}else{
ui->label_state->setText("保存照片失敗!!!");
}
}
錄像代碼
開啓錄像
void OpenCVManager::startRecord(QString pathFile)
{
// 多線程處理
QMetaObject::invokeMethod(this, "slot_startRecord",
Qt::DirectConnection, Q_ARG(QString, pathFile));
}
void OpenCVManager::slot_startRecord(QString filePath)
{
if(_pVideoWrite)
{
qDebug() << __FILE__ << __LINE__ << "It's recording!!!";
return;
}
_pVideoWrite = new cv::VideoWriter;
QString ext = filePath.mid(filePath.lastIndexOf(".") + 1);
int cvFourcc = 0;
if(ext == "mpg")
{
cvFourcc = CV_FOURCC('D','I','V','X');
qDebug() << __FILE__ << __LINE__<< ext << "DIVX" << cvFourcc;
}else if(ext == "avi")
{
cvFourcc = CV_FOURCC('M','J','P','G');
qDebug() << __FILE__ << __LINE__<< ext << "MJPG" << cvFourcc;
}else if(ext == "mp4")
{
// mp4目前錄製不成功(可以生成文件,但是打開失敗)
// cvFourcc = CV_FOURCC('M','P','4','2');
cvFourcc = CV_FOURCC('M','J','P','G');
// cvFourcc = CV_FOURCC('I', 'Y', 'U', 'V');
qDebug() << __FILE__ << __LINE__<< ext << "MP42" << cvFourcc;
}
_pVideoWrite->open(filePath.toStdString(), cvFourcc, 25, cv::Size(_width, _height));
_recordFilePath = filePath;
_recording = true;
}
錄像過程
void OpenCVManager::slot_captrueFrame()
{
if(!_running)
{
return;
}
if(_pVideoCapture->isOpened())
{
cv::Mat mat;
*_pVideoCapture >> mat;
if(_showProperty)
{
cv::putText(mat, QString("brightness: %1").arg(_brightness).toStdString(),
cvPoint(0, 30), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString(" contrast: %1").arg(_contrast ).toStdString(),
cvPoint(0, 60), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString("saturation: %1").arg(_saturation).toStdString(),
cvPoint(0, 90), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString(" hue: %1").arg(_hue ).toStdString(),
cvPoint(0, 120), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString(" gain: %1").arg(_gain ).toStdString(),
cvPoint(0, 150), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString(" exposure: %1").arg(_exposure ).toStdString(),
cvPoint(0, 180), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
cv::putText(mat, QString("press ESC out").toStdString(),
cvPoint(0, 210), cv::FONT_HERSHEY_COMPLEX, 1.0, cv::Scalar(255));
}
if(_recording)
{
_pVideoWrite->write(mat);
}
emit signal_captureOneFrame(mat);
QTimer::singleShot(10, this, SLOT(slot_captrueFrame()));
}
}
關閉錄像
void OpenCVManager::stopRecord()
{
// 多線程處理
QMetaObject::invokeMethod(this, "slot_stopRecord", Qt::DirectConnection);
}
void OpenCVManager::slot_stopRecord()
{
if(_pVideoWrite)
{
_recording = false;
_pVideoWrite->release();
delete _pVideoWrite;
_pVideoWrite = 0;
}
}
入坑
入坑一:錄製視頻保存爲空
解決方法:
編解碼器得問題,cv::VideoWrite查閱相關資料發現其只支持固定的幾個格式,其中就包括avi。
入坑二:錄製視頻奔潰
原因:
因爲初始設置攝像頭的寬高(400 x 400),根據測試推斷攝像頭會默認給最接近初始化設置的分辨率,但是卻不是直接是設置的(400 x 400)而是返回了最接近的分辨率(320 x 240),除非設置的分辨率正好是攝像頭本身支持。
所以設置分辨率是需要攝像頭硬件支持。
解決方法:
進一步驗證同時解決該問題
原博主博客地址:https://blog.csdn.net/qq21497936
原博主博客導航:https://blog.csdn.net/qq21497936/article/details/102478062
本文章博客地址:https://blog.csdn.net/qq21497936/article/details/102993007