Adding gamma effect to a clip with mute effect, while previewing it.

Application: Kdenlive (kdenlive), signal SIGSEGV
[Current thread is 0 (LWP 24440)]

Thread 3 (Thread 0xad1bbb90 (LWP 25238)):
#0  0xb7fc7424 in __kernel_vsyscall ()
#1  0xb6547f45 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/i686/cmov/libpthread.so.0
#2  0xb664c79d in __pthread_cond_wait (cond=0xa4a232c, mutex=0xa4a235c) at forward.c:139
#3  0xb460f47c in consumer_thread (arg=0xa4a2218) at consumer_sdl_preview.c:381
#4  0xb6544495 in start_thread (arg=0xad1bbb90) at pthread_create.c:300
#5  0xb663da5e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130

Thread 2 (Thread 0xac9bab90 (LWP 25248)):
#0  0xb7fc7424 in __kernel_vsyscall ()
#1  0xb6548272 in pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i686/../i486/pthread_cond_timedwait.S:179
#2  0xb664c7f4 in __pthread_cond_timedwait (cond=0xa4b1758, mutex=0xa4b1740, abstime=0xac9ba108) at forward.c:152
#3  0xb7f9b9f9 in mlt_consumer_get_frame (this=0xa4b16a8) at mlt_consumer.c:498
#4  0xb7f9bc50 in mlt_consumer_rt_frame (this=0xa4b16a8) at mlt_consumer.c:896
#5  0xb460fdda in consumer_thread (arg=0xa4b16a8) at consumer_sdl_still.c:562
#6  0xb6544495 in start_thread (arg=0xac9bab90) at pthread_create.c:300
#7  0xb663da5e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130

Thread 1 (Thread 0xb5bc8710 (LWP 24440)):
[KCrash Handler]
#6  ~QObjectPrivate (this=0xa99e120) at kernel/qobject.cpp:128
#7  0xb73a31d1 in ~QObject (this=0xca019d0) at kernel/qobject.cpp:865
#8  0xb6f8e187 in ~QGraphicsItemAnimation (this=0xca019d0) at graphicsview/qgraphicsitemanimation.cpp:200
#9  0x0810eb10 in CustomTrackView::mouseMoveEvent (this=0xc9efdb8, event=0xbffe376c) at /home/mcfrisk/src/kdenlive-svn/src/customtrackview.cpp:570
#10 0xb699421d in QWidget::event (this=0xc9efdb8, event=0xbffe376c) at kernel/qwidget.cpp:7506
#11 0xb6d6e3e3 in QFrame::event (this=0xc9efdb8, e=0xbffe376c) at widgets/qframe.cpp:559
#12 0xb6e0e39f in QAbstractScrollArea::viewportEvent (this=0xc9efdb8, e=0xa99e120) at widgets/qabstractscrollarea.cpp:962
#13 0xb6fb7682 in QGraphicsView::viewportEvent (this=0xc9efdb8, event=0xbffe376c) at graphicsview/qgraphicsview.cpp:2897
#14 0xb6e109a5 in QAbstractScrollAreaFilter::eventFilter (this=0xa78b7a0, o=0xa78b968, e=0xbffe376c) at widgets/qabstractscrollarea_p.h:100
#15 0xb738ac4a in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0xa0c7310, receiver=0xa78b968, event=0xbffe376c) at kernel/qcoreapplication.cpp:726
#16 0xb693d79a in QApplicationPrivate::notify_helper (this=0xa0c7310, receiver=0xa78b968, e=0xbffe376c) at kernel/qapplication.cpp:4053
#17 0xb6946441 in QApplication::notify (this=0xbffe4ff4, receiver=0xa78b968, e=0xbffe376c) at kernel/qapplication.cpp:3759
#18 0xb7d4e5ed in KApplication::notify (this=0xbffe4ff4, receiver=0xa78b968, event=0xbffe376c) at ../../kdeui/kernel/kapplication.cpp:307
#19 0xb738ba2b in QCoreApplication::notifyInternal (this=0xbffe4ff4, receiver=0xa78b968, event=0xbffe376c) at kernel/qcoreapplication.cpp:610
#20 0xb69454ae in QApplicationPrivate::sendMouseEvent (receiver=0xa78b968, event=0xbffe376c, alienWidget=0xa78b968, nativeWidget=0xc9efdb8, buttonDown=0xb71ea9e0, lastMouseReceiver=@0xb71ea9e4)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#21 0xb69b4dc5 in QETWidget::translateMouseEvent (this=0xc9efdb8, event=0xbffe4964) at kernel/qapplication_x11.cpp:4448
#22 0xb69b3b1a in QApplication::x11ProcessEvent (this=0xbffe4ff4, event=0xbffe4d1c) at kernel/qapplication_x11.cpp:3645
#23 0xb69de9a2 in x11EventSourceDispatch (s=0xa0ca500, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#24 0xb6088848 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#25 0xb608bd73 in ?? () from /usr/lib/libglib-2.0.so.0
#26 0x0a0c8f10 in ?? ()
#27 0x00000000 in ?? ()