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Diffstat (limited to 'examples/webkit/imageanalyzer/imageanalyzer.cpp')
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diff --git a/examples/webkit/imageanalyzer/imageanalyzer.cpp b/examples/webkit/imageanalyzer/imageanalyzer.cpp new file mode 100644 index 0000000..1d0ee45 --- /dev/null +++ b/examples/webkit/imageanalyzer/imageanalyzer.cpp @@ -0,0 +1,222 @@ +/**************************************************************************** +** +** 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 Toolkit. +** +** $QT_BEGIN_LICENSE:BSD$ +** 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 <QNetworkReply> +#include <QNetworkRequest> +#include <QNetworkAccessManager> +#include <QNetworkDiskCache> +#include "imageanalyzer.h" + +/*! + * This class operates as follows: + * Parent calls the slot startAnalysis which shoves a list of QStrings into URLQueue and then calls fetchURLs. + * FetchURLs sends out HTTP GETs for each image it can't get out of the cache. + * As the responses come in, handleReply trys to create an image out of each and pushes those images into imageQueue. + * On the last (detected by no outstandingFetches and URLQueue.isEmpty()) call to queueImage (from handleReply) + * a thread is forked to process all the images. When it finishes, it emits a finished signal that is received + * by our JavaScript code. + */ + +//! [ ImageAnalyzer - Constructor ] +ImageAnalyzer::ImageAnalyzer(QNetworkDiskCache* netcache, QObject* parent) + : QObject(parent), m_cache(netcache), m_outstandingFetches(0) +{ + /* ImageAnalyzer only wants to receive http responses + for requests that it makes, so that's why it has its own + QNetworkAccessManager. */ + m_network = new QNetworkAccessManager(this); + m_watcher = new QFutureWatcher<QRgb>(this); + /* We want to share a cache with the web browser, + in case it has some images we want: */ + m_network->setCache(m_cache); + + QObject::connect(m_network, SIGNAL(finished(QNetworkReply*)), + this, SLOT(handleReply(QNetworkReply*))); + QObject::connect(m_watcher, SIGNAL(finished()), + this, SLOT(doneProcessing())); + QObject::connect(m_watcher, SIGNAL(progressValueChanged(int)), + this, SLOT(progressStatus(int))); +} +//! [ ImageAnalyzer - Constructor ] +ImageAnalyzer::~ImageAnalyzer() +{ + delete(m_watcher); +} + + +QRgb ImageAnalyzer::lastResults() +{ + int rTot = 0; + int bTot = 0; + int gTot = 0; + int count = m_watcher->future().results().size(); + foreach(const QRgb & triplet, m_watcher->future().results()) + { + rTot += qRed(triplet); + bTot += qBlue(triplet); + gTot += qGreen(triplet); + } + return qRgb(rTot/count, bTot/count, gTot/count); +} + +float ImageAnalyzer::lastRed() { return qRed(lastResults())/2.55; } +float ImageAnalyzer::lastGreen() { return qGreen(lastResults())/2.55; } +float ImageAnalyzer::lastBlue() { return qBlue(lastResults())/2.55; } + +void ImageAnalyzer::progressStatus(int newstat) +{ + emit updateProgress(newstat, m_watcher->progressMaximum()); +} + + +bool ImageAnalyzer::isBusy() +{ + return m_watcher->isRunning(); +} + + +//! [ ImageAnalyzer - startAnalysis ] +void ImageAnalyzer::startAnalysis(const QStringList & urls) +{ + m_URLQueue = urls; + fetchURLs(); +} +//! [ ImageAnalyzer - startAnalysis ] + +/*! + * Analyzes the entire queue - just starts all our http GETs. + */ +//! [ ImageAnalyzer - fetchURLs ] +void ImageAnalyzer::fetchURLs() +{ + while (!m_URLQueue.isEmpty()) + { + QString url = m_URLQueue.takeFirst(); + QUrl URL = QUrl(url); + QIODevice * pData = m_cache->data(URL); + // Is image already loaded in cache? + if (pData == 0) { + // HTTP Get image over network. + m_outstandingFetches++; + QNetworkRequest request = QNetworkRequest(URL); + request.setRawHeader("User-Agent", "Nokia - Custom QT app"); + m_network->get(request); + } else { + // Get image from cache + QImage image; + image.load(pData, 0); + if (!image.isNull()) + queueImage(image); + delete(pData); + } + } +} +//! [ ImageAnalyzer - fetchURLs ] +/* + * Slot to handle the incoming responses from our http GETs + */ +//! [ ImageAnalyzer - handleReply ] +void ImageAnalyzer::handleReply(QNetworkReply * pReply) +{ + m_outstandingFetches--; + if (pReply->error()) { + qDebug() << "Error code" << pReply->error(); + qDebug() << "Http code" << pReply->attribute(QNetworkRequest::HttpStatusCodeAttribute); + return; + } + QImage image; + image.load(pReply, 0); + pReply->deleteLater(); + if (image.isNull()) { + qDebug() << "bad image"; + qDebug() << pReply->rawHeaderList(); + foreach(QByteArray element, pReply->rawHeaderList()) { + qDebug() << element << " = " << pReply->rawHeader(element); + } + return; + } + queueImage(image); +} +//! [ ImageAnalyzer - handleReply ] + +void ImageAnalyzer::doneProcessing() +{ + m_imageQueue = QList<QImage>(); + emit finishedAnalysis(); +} +//! [ ImageAnalyzer - queueImage ] +void ImageAnalyzer::queueImage(QImage img) +{ + if (!img.isNull()) + m_imageQueue << img; + + if (m_outstandingFetches == 0 && m_URLQueue.isEmpty()) { + m_watcher->setFuture(QtConcurrent::mapped(m_imageQueue, averageRGB)); + } +} +//! [ ImageAnalyzer - queueImage ] + +//! [ ImageAnalyzer - averageRGB ] +QRgb averageRGB(const QImage &img) +{ + int pixelCount = img.width() * img.height(); + int rAvg, gAvg, bAvg; + + // We waste some time here: + for (int timeWaster=0; timeWaster < 100; timeWaster++) { + quint64 rTot = 0; + quint64 gTot = 0; + quint64 bTot = 0; + for (int i=0; i < img.width(); i++) { + for (int j=0; j < img.height(); j++) { + QRgb pixel = img.pixel(i,j); + rTot += qRed(pixel); + gTot += qGreen(pixel); + bTot += qBlue(pixel); + } + } + rAvg = (rTot)/(pixelCount); + gAvg = (gTot)/(pixelCount); + bAvg = (bTot)/(pixelCount); + } + return qRgb(rAvg, gAvg, bAvg); +} +//! [ ImageAnalyzer - averageRGB ] |