Linux versions 2.8.x, 2.9.x, 3.0.x
Gwenview 2.7.4, 2.7.x

Details when run from terminal:

sonja@sonja:~/Desktop$ gwenview
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
gwenview(19821)/kdeui (kdelibs): Attempt to use QAction "edit_redo" with KXMLGUIFactory! 
gwenview(19821)/kdeui (kdelibs): Attempt to use QAction "edit_undo" with KXMLGUIFactory! 
gwenview(19821) KSharedUiServerProxy::KSharedUiServerProxy: kuiserver registered
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
QPainter::begin: Paint device returned engine == 0, type: 2
gwenview(19821) Gwenview::ThumbnailViewHelperPrivate::addActionToMenu: Unknown action edit_tags 
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
"/usr/bin/gwenview(19821)" Soprano: "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"
"/usr/bin/gwenview(19821)" Soprano: "QLocalSocket::connectToServer: Invalid name"
gwenview(19821) KSambaSharePrivate::isSambaInstalled: Samba is not installed!
gwenview(19821) KSambaSharePrivate::isSambaInstalled: Samba is not installed!
Qt has caught an exception thrown from an event handler. Throwing
exceptions from an event handler is not supported in Qt. You must
reimplement QApplication::notify() and catch all exceptions there.

terminate called after throwing an instance of 'std::bad_alloc'
  what():  std::bad_alloc
KCrash: Application 'gwenview' crashing...
libpng error: Read Error
gwenview(19821) Gwenview::ThumbnailThread::loadThumbnail: Could not generate thumbnail for file "file:///home/taal/photographs/nature/mountains/panorama/img_6559-img_6568_rock_stratigraphy_8372.png" 
KCrash: Attempting to start /usr/lib/kde4/libexec/drkonqi from kdeinit
sock_file=/home/sonja/.kde/socket-sonja/kdeinit4__0
sonja@sonja:~/Desktop$ gwenview --version
Qt: 4.7.4
KDE Development Platform: 4.7.4 (4.7.4)
Gwenview: 2.7.4
sonja@sonja:~/Desktop$ 

When running just Gwenview and whether saving a file, dragging to move a file in the directory tree, or generating thumbnails in the browse window, Gwenview will abruptly disappear.  About 20-30 seconds later a crash dialogue appears.  During this time it is impossible to start any other application.  In each instance I get the same error "terminate called after throwing an instance of 'std::bad_alloc'"  This problem happens on a number of different machines: an Asus EEE Pc, two Asus desktops, and an Intel desktop.  The Asus EEE is running Kubuntu 12.04 LTS, the remaining machines are running Ubuntu Studio.  All machines have the most recent updates and always do.  Gwenview has been doing this for as long as I can remember and I'm tired of it and therefore submitting a bug.

My estimation is that there is a problem in moving files by dragging to the folder tree while thumbnails are generating.  The images that thumbnails are being produced from are PNG and TIF images ranging in size from a few megabytes to as much as 500 mb (these are panoramas)

Reproducible: Always

Steps to Reproduce:
A. Drag an image in the browse window to the folder tree while thumbnails are generating (crash)
B. Rename an image in the browse window (whether or not then dragging an image to the folder tree) and a crash results, often while a thumbnail is being generated.
C. Saving a file then after dragging an image in the browser window to the folder tree (whether or not thumbnails are being generated).

Actual Results:  
Gwenview disappears; it's not possible to start any application for 20-30 seconds then a crash dialogue appears for Gwenview.  It is also not possible to use Backtrace because the applications needed to be installed cannot be found.

Expected Results:  
Not crashed :)  If Gwenview cannot handle images as large as 500 mb then it should not generate a thumbnail of it and should not permit viewing.

Please see details for output when running gwenview from a terminal.

Gwenview is the ONLY Linux application I have that crashes on a regular basis.  That is, I expect that it will crash and I use it under these less than satisfactory conditions.