14.1.148. tablet_qt/graphics/imagefunc.cpp

/*
    Copyright (C) 2012-2019 Rudolf Cardinal (rudolf@pobox.com).

    This file is part of CamCOPS.

    CamCOPS is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    CamCOPS is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with CamCOPS. If not, see <http://www.gnu.org/licenses/>.
*/

#include "imagefunc.h"
#include <QVideoFrame>


namespace imagefunc {


QImage imageFromVideoFrame(const QVideoFrame& buffer)
{
    QImage img;
    QVideoFrame frame(buffer);  // make a copy we can call map (non-const) on
    frame.map(QAbstractVideoBuffer::ReadOnly);
    const QImage::Format imageFormat = QVideoFrame::imageFormatFromPixelFormat(
                frame.pixelFormat());
    // BUT the frame.pixelFormat() is QVideoFrame::Format_Jpeg, and this is
    // mapped to QImage::Format_Invalid by
    // QVideoFrame::imageFormatFromPixelFormat
    if (imageFormat != QImage::Format_Invalid) {
        img = QImage(frame.bits(),
                     frame.width(),
                     frame.height(),
                     // frame.bytesPerLine(),
                     imageFormat);
    } else {
        // e.g. JPEG
        const int nbytes = frame.mappedBytes();
        img = QImage::fromData(frame.bits(), nbytes);
    }
    frame.unmap();
    return img;
}


}  // namespace imagefunc