examples/Qt/facerecgapp/dummythumbnailer.cpp

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#include "dummythumbnailer.h"
#include <QImageReader>
#include <QFile>
#include <QFileInfo>
#include <QDebug>
#include <QDir>


#if defined (__SYMBIAN32__) || defined(_WIN32)
const QString gThumbnailPath("E:/Thumbnails/");
#else
const QString gThumbnailPath("./Thumbnails/");
#endif

DummyFaceThumbnailer::DummyFaceThumbnailer(QObject *parent)
    : XQFaceThumbnailer(parent)
{

}

DummyFaceThumbnailer::~DummyFaceThumbnailer()
{

}

void DummyFaceThumbnailer::createThumbnail(const QString &sourceId, XQFaceThumbnailer::ThumbnailSizeHint sizeHint, const QSize &preferredSize)
{
    /*create requested thumbnail size*/
    QImageReader reader(sourceId);

    /*get the size information*/
    QSize imageSize = reader.size();

    /*If the image size is not valid or the image's size > preferred size, set preferred size as scaled one*/
    if(!(imageSize.isValid()) || ((imageSize.width() * imageSize.height()) > (preferredSize.width()* preferredSize.height())))
    {
        const QSize prefszpreserveAR (preferredSize.width(),
                                        (imageSize.height()*preferredSize.width())/imageSize.width());

        reader.setScaledSize(prefszpreserveAR);
    }

    /*emit thumbnail created*/
    emit thumbnailCreated(reader.read(), sourceId, sizeHint);
}

void DummyFaceThumbnailer::createFaceThumbnail(const QString &sourceId, const QSize &sourceSize, const QRect &thumbnailRect)
{
    /*If thumbnail rect passed by user is not valid, return null string*/
    if (!(thumbnailRect.isValid()) || thumbnailRect.isNull())
    {
        /*emit a empty string for this image*/
        emit faceThumbnailCreated(QString(), sourceId, sourceSize, thumbnailRect);
        return;
    }

    /*Read image*/
    QImageReader reader(sourceId);
    reader.setScaledSize(sourceSize);
    QImage image = reader.read();

    /*if image is null*/
    if (image.isNull())
    {
        /*emit a empty string for this image*/
        emit faceThumbnailCreated(QString(), sourceId, sourceSize, thumbnailRect);
        return;
    }


    QImage faceimg;

    /*Prior calculation for extracting the thumbnail from right area*/
    int perw =  thumbnailRect.width() * 0.4;
    int perh =  thumbnailRect.height() * 0.4;

    int x1 = thumbnailRect.x()- perw;
    if (x1 < 0)
    {
        x1 = 0;
    }

    int y1 = thumbnailRect.y()- 2*perh;
    if (y1 < 0)
    {
        y1 = 0;
    }

    int x2 = thumbnailRect.width() + thumbnailRect.x() + perw;
    if (x2 > image.width())
    {
        x2 = image.width();
    }

    int y2 = thumbnailRect.height() + thumbnailRect.y() + 2*perh;
    if (y2 > image.height())
    {
        y2 = image.height();
    }


    int tmpx = x1;
    int tmpy = y1;
    int tmpw = x2-x1;
    int tmph = y2-y1;


    if(tmpx < 0)
    {
        tmpx=0;
    }

    if (tmpy < 0)
    {
        tmpy=0;
    }

    if(tmpx + tmpw > image.width())
    {
        tmpw = image.width()-tmpx;
    }

    if (tmpy + tmph > image.height())
    {
        tmph = image.height()-tmpy;
    }

    /*create the required size*/
    QRect temp(tmpx,tmpy,tmpw,tmph);
    faceimg = image.copy(temp);


    /*create thumbnailpath*/
    QString tnPath(gThumbnailPath);

    QDir dir(gThumbnailPath);

    if(!dir.exists())
      {
      dir.mkpath(gThumbnailPath);
      }

    /*Append the basename of the sourcefile*/
    QFileInfo fileInfo(sourceId);
    tnPath.append(fileInfo.completeBaseName());
    tnPath.append('_');

    /*Append top left x coordinate*/
    tnPath.append(QString().setNum(thumbnailRect.x()));
    tnPath.append('_');

    /*Append top left y coordinate*/
    tnPath.append(QString().setNum(thumbnailRect.y()));
    tnPath.append('_');

    /*Append width info*/
    tnPath.append(QString().setNum(thumbnailRect.width()));
    tnPath.append('_');

    /*Append height info*/
    tnPath.append(QString().setNum(thumbnailRect.height()));
    tnPath.append(QString(".jpg"));

    /*Save the image in that path and emit appropriate signal*/
    if(faceimg.save(tnPath, "JPG"))
    {
        emit faceThumbnailCreated(tnPath, sourceId, sourceSize, thumbnailRect);
    }
    else
    {
        qDebug()<<"Saving the thumbnail failed in dummy thumbnailer. Check if path exists!";
        emit faceThumbnailCreated(QString(), sourceId, sourceSize, thumbnailRect);
    }
}

void DummyFaceThumbnailer::thumbnailNotUsed(const QStringList &thumbnailPaths)
{
    foreach(QString tnPath, thumbnailPaths)
    {
        /*Check whether the file exists*/
        if(QFile::exists(tnPath))
        {
            /*remove that file*/
            QFile file(tnPath);
            file.remove();
        }
    }
}

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