Still Image capture using Qt Mobility

Article Metadata

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Article

Created: skumar_rao (27 Mar 2010)

Last edited: hamishwillee (26 Jul 2012)

ID		Creation date	27th Mar 2010
Platform	S60 5th Edition	Tested on devices	Nokia N97 Mini
Category	Qt Mobility	Subcategory	Multimedia

Keywords (APIs, classes, methods, functions): QCamera, QStillImageCapture

Overview

This article demonstrate how to capture still images using Qt Mobility

Project configuration file (.Pro file)

• Add the Qt Mobility project configuration option in the .Pro file as shown below

CONFIG += mobility
MOBILITY += multimedia

Header File

#include <qcamera.h>
#include <qstillimagecapture.h>
 
public slots:
    void captureImage();    
    void error(QCamera::Error);
    void imageCaptured(const QString &fileName, const QImage &preview);
private:
    void InitCamera();
 
private:    
    QCamera* m_camera;
    QStillImageCapture* m_stillImageCapture;

Source File

void ImageCapture::InitCamera() {
    QByteArray cameraDevices = QCamera::availableDevices()[0];
    m_camera = new QCamera(cameraDevices);
 
    connect(m_camera, SIGNAL(error(QCamera::Error)), this, SLOT(error(QCamera::Error)));
 
    m_camera->setFocusMode(QCamera::AutoFocus);
 
    m_stillImageCapture = new QStillImageCapture(m_camera);
    connect(m_stillImageCapture, SIGNAL(imageCaptured(QString,QImage)), this, SLOT(imageCaptured(QString,QImage)));
 
    if (m_camera->state() == QCamera::ActiveState) {
        m_camera->stop();
        }
    m_camera->start();
    }

void ImageCapture::error(QCamera::Error e) {
       switch (e) {
        case QCamera::CameraError: {
            QMessageBox::warning(this, "Camera error", "General camera error");
            break;
            }
        case QCamera::NotReadyToCaptureError: {
            QMessageBox::warning(this, "Camera error", "Camera not ready to capture image");
            break;
            }
        case QCamera::InvalidRequestError: {
            QMessageBox::warning(this, "Camera error", "Invalid request");
            break;
            }
        case QCamera::ServiceMissingError: {
            QMessageBox::warning(this, "Camera error", "Service missing");
            break;
            }
        case QCamera::NotSupportedFeatureError: {
            QMessageBox::warning(this, "Camera error", "Not supported feature");
            break;
            }
        default:
            break;
        };
    }

void ImageCapture::captureImage() {
    if (m_stillImageCapture->isReadyForCapture()) {
        m_stillImageCapture->capture(QString("camera_capture.jpg"));
        }
    else {
        QMessageBox::warning(this, "Camera error", "Camera not ready");
        }
 
    }

void ImageCapture::imageCaptured(const QString &fileName, const QImage &preview) {
    QMessageBox::information(this, "Image Capatured", fileName);
    }

Classes

• QCamera
• QStillImageCapture

Reference links

• Qt - cross-platform application and UI framework
• Qt Mobility API
• New Qt APIs Beta - Mobility Project
• SDK help

--skumar_rao 16:28, 27 March 2010 (UTC)