commit 6df0f2e9fe520f591cdf9eae66ceb051c4c07808
parent 19ffe0664869a7954ca9688f35270631bec39b69
Author: Christian Grothoff <christian@grothoff.org>
Date: Sat, 19 Dec 2009 13:34:42 +0000
qt
Diffstat:
1 file changed, 174 insertions(+), 0 deletions(-)
diff --git a/src/plugins/thumbnailqt_extractor.cc b/src/plugins/thumbnailqt_extractor.cc
@@ -0,0 +1,174 @@
+/*
+ This file is part of libextractor.
+ (C) 2006, 2009 Vidyut Samanta and Christian Grothoff
+
+ libextractor 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 2, or (at your
+ option) any later version.
+
+ libextractor 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 libextractor; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * @file thumbnailqt_extractor.cc
+ * @author Nils Durner
+ * @brief this extractor produces a binary (!) encoded
+ * thumbnail of images (using Qt).
+ */
+
+#include "platform.h"
+#include "extractor.h"
+#include <Qt/qpixmap.h>
+#include <Qt/qbytearray.h>
+#include <Qt/qbuffer.h>
+#include <Qt/qapplication.h>
+#include <pthread.h>
+
+#ifdef HAVE_QT_SVG
+ #include <Qt/qsvgrenderer.h>
+ #include <Qt/qpainter.h>
+#endif
+
+#define THUMBSIZE 128
+
+extern "C"
+{
+
+int
+EXTRACTOR_thumbnailqt_extract (const char *data,
+ size_t size,
+ EXTRACTOR_MetaDataProcessor proc,
+ void *proc_cls,
+ const char *options)
+{
+ QImage *img;
+ QByteArray bytes;
+ QBuffer buffer;
+ unsigned long width;
+ unsigned long height;
+ char format[64];
+ QImage::Format colors;
+
+ /* Determine image format to use */
+ if (options == NULL)
+ colors = QImage::Format_Indexed8;
+ else
+ switch (atoi(options))
+ {
+ case 1:
+ colors = QImage::Format_Mono;
+ break;
+ case 8:
+ colors = QImage::Format_Indexed8;
+ break;
+ case 16:
+ case 24:
+ colors = QImage::Format_RGB32;
+ break;
+ default:
+ colors = QImage::Format_ARGB32;
+ break;
+ }
+ QByteArray din (data, (int) size);
+
+#ifdef HAVE_QT_SVG
+ /* Render SVG image */
+ QSvgRenderer svg;
+ QSize qsize;
+ if (svg.load(din))
+ {
+ qsize = svg.defaultSize();
+ img = new QImage(qsize, QImage::Format_ARGB32);
+ QPainter painter(img);
+ painter.setViewport(0, 0, qsize.width(), qsize.height());
+ painter.eraseRect(0, 0, qsize.width(), qsize.height());
+ svg.render(&painter);
+ }
+ else
+#endif
+ {
+ /* Load image */
+ img = new QImage();
+ img->loadFromData(din);
+ }
+
+ height = img->height();
+ width = img->width();
+ snprintf(format,
+ sizeof(format),
+ "%ux%u",
+ (unsigned int) width,
+ (unsigned int) height);
+ if (0 != proc (proc_cls,
+ "thumbnailqt",
+ EXTRACTOR_METATYPE_IMAGE_DIMENSIONS,
+ EXTRACTOR_METAFORMAT_UTF8,
+ "text/plain",
+ format,
+ strlen(format)+1))
+ {
+ delete img;
+ return 1;
+ }
+ if (height == 0)
+ height = 1;
+ if (width == 0)
+ width = 1;
+
+ /* Change color depth */
+ QImage thumb = img->convertToFormat(colors);
+ delete img;
+
+ /* Resize image
+ *
+ * Qt's scaled() produces poor quality if the image is resized to less than
+ * half the size. Therefore, we resize the image in multiple steps.
+ * http://lists.trolltech.com/qt-interest/2006-04/msg00376.html */
+ while ( (width > THUMBSIZE) || (height > THUMBSIZE) )
+ {
+ width /= 2;
+ if (width < THUMBSIZE)
+ width = THUMBSIZE;
+ height /= 2;
+ if (height < THUMBSIZE)
+ height = THUMBSIZE;
+ thumb = thumb.scaled(width,
+ height,
+ Qt::KeepAspectRatio,
+ Qt::SmoothTransformation);
+ }
+ buffer.setBuffer(&bytes);
+ buffer.open(QIODevice::WriteOnly);
+ thumb.save(&buffer, "PNG");
+ return proc (proc_cls,
+ "thumbnailqt",
+ EXTRACTOR_METATYPE_THUMBNAIL,
+ EXTRACTOR_METAFORMAT_BINARY,
+ "image/png",
+ bytes.data(),
+ bytes.length());
+}
+
+
+int
+EXTRACTOR_thumbnail_extract (const unsigned char *data,
+ size_t size,
+ EXTRACTOR_MetaDataProcessor proc,
+ void *proc_cls,
+ const char *options)
+{
+ return EXTRACTOR_thumbnail_extract (data, size, proc, proc_cls, options);
+}
+
+} // extern "C"
+
+/* end of thumbnailqt_extractor.cc */
