/**************************************************************************** ** ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the examples of the Qt Mobility Components. ** ** $QT_BEGIN_LICENSE:BSD$ ** You may use this file under the terms of the BSD license as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor ** the names of its contributors may be used to endorse or promote ** products derived from this software without specific prior written ** permission. ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "thumbnailcache.h" #include "thumbnailmodel.h" #include <QtCore/qcryptographichash.h> #include <QtCore/qcoreapplication.h> #include <QtCore/qcoreevent.h> #include <QtCore/qdir.h> #include <QtCore/qurl.h> #include <QtGui/qimagereader.h> #include <QtGui/qpixmap.h> #if (QT_VERSION < QT_VERSION_CHECK(4, 7, 0)) uint qHash(const QUrl &url) { return qHash(url.toString()); } #endif class Thumbnail { public: Thumbnail(const QUrl &url) : url(url) { } const QUrl url; QPixmap pixmap; private: ThumbnailCache *cache; }; class ThumbnailEvent : public QEvent { public: ThumbnailEvent(const QUrl &url, const QImage &image) : QEvent(QEvent::User) , url(url) , image(image) { } const QUrl url; const QImage image; }; ThumbnailCache::ThumbnailCache(QObject *parent) : QThread(parent) #if defined(Q_OS_SYMBIAN) || defined(Q_WS_MAEMO_5) || defined(Q_WS_MAEMO_6) , cache(25) #else , cache(150) #endif , cancelled(false) { start(QThread::LowestPriority); } ThumbnailCache::~ThumbnailCache() { { QMutexLocker locker(&mutex); cancelled = true; waitCondition.wakeOne(); } wait(); } QPixmap ThumbnailCache::thumbnail(const QUrl &url) { QMutexLocker locker(&mutex); if (Thumbnail *thumbnail = cache.object(url)) { return thumbnail->pixmap; } else { pendingUrls.enqueue(url); cache.insert(url, new Thumbnail(url)); waitCondition.wakeOne(); return QPixmap(); } } bool ThumbnailCache::event(QEvent *event) { if (event->type() == QEvent::User) { ThumbnailEvent *thumbnailEvent = static_cast<ThumbnailEvent *>(event); QMutexLocker locker(&mutex); if (Thumbnail *thumbnail = cache.object(thumbnailEvent->url)) { thumbnail->pixmap = QPixmap::fromImage(thumbnailEvent->image); locker.unlock(); emit thumbnailReady(); } return true; } else { return QThread::event(event); } } void ThumbnailCache::run() { QMutexLocker locker(&mutex); while(!cancelled) { if (!pendingUrls.isEmpty()) { const QUrl url = pendingUrls.dequeue(); if (cache.contains(url)) { locker.unlock(); QImage image = loadImage(url); locker.relock(); if (!image.isNull()) QCoreApplication::postEvent(this, new ThumbnailEvent(url, image)); } } else { waitCondition.wait(&mutex); } } } QImage ThumbnailCache::loadImage(const QUrl &url) const { const QString fileName = thumbnailPath(url); QImageReader reader(fileName); reader.setQuality(25); if (reader.supportsOption(QImageIOHandler::Size)) { QSize size = reader.size(); if (!reader.supportsOption(QImageIOHandler::ScaledSize) && (size.width() > 1280 || size.height() > 1280)) { return QImage(); } if (size.width() > ThumbnailModel::thumbnailSize.width() || size.height() > ThumbnailModel::thumbnailSize.height()) { size.scale(ThumbnailModel::thumbnailSize, Qt::KeepAspectRatio); } reader.setScaledSize(size); } else { reader.setScaledSize(ThumbnailModel::thumbnailSize); } return reader.read(); } QString ThumbnailCache::thumbnailPath(const QUrl &url) const { #if defined(Q_OS_UNIX) && !(defined(Q_OS_SYMBIAN) || defined(Q_OS_MAC)) #if defined(Q_WS_MAEMO_5) QString thumbnailPath = QDir::homePath() + QLatin1String("/.thumbnails/cropped/") + QCryptographicHash::hash(url.toString().toUtf8(), QCryptographicHash::Md5).toHex() + QLatin1String(".jpeg"); #elif defined(Q_WS_MAEMO_6) QString thumbnailPath = QDir::homePath() + QLatin1String("/.thumbnails/grid/") + QCryptographicHash::hash(url.toString().toUtf8(), QCryptographicHash::Md5).toHex() + QLatin1String(".jpeg"); #else QString thumbnailPath = QDir::homePath() + QLatin1String("/.thumbnails/normal/") + QCryptographicHash::hash(url.toEncoded(), QCryptographicHash::Md5).toHex() + QLatin1String(".png"); #endif if (QFile::exists(thumbnailPath)) return thumbnailPath; #endif return url.toLocalFile(); }
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