Bug 461507

SUMMARY
***
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See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
***

Whenever I try to run the automatic scene detection to create labels at the scene edges, kdenlive crashes after the process finishes.

(And I am sorry, if the details are not helpful, I am a bit new to creating crash reports)

STEPS TO REPRODUCE
0. set your system to German (de_AT.UTF-8), with LANG=C it seems to work fine, just switching the language in the UI is not enough)
1. open kdenlive
2. open a video file
3. select Clip Job -> Automatic Scene split
4. make sure "Add clip markers" is enabled (if I select "Cut scenes" instead, everything works fine)
5. wait until ffmpeg has finished

OBSERVED RESULT
After a line starting with `GOR RESULTS` is printed to the log (with timestamps that might be reasonable output, making me think that the ffmpeg output is parsed correctly), kdenlive crashes (unfortunately with different messages each time). Now that I try to properly reproduce this for the bug report, I also notice that sometimes kdenlive doesn't crash, but just freeze.

This is the most helpful backtrace I can achieve:

GOR RESULTS:  (120.9, 120.967, 153.633, 153.733, 197, 197.067, 377.9, 404.833, 404.867, 493.967, 494, 576.267, 624.233, 624.3, 662.567, 687.7, 687.767, 722.467, 722.6, 862.033, 862.133, 961.867, 962.133, 1071.37, 1090.3, 1317.13, 1317.17, 1336.23, 1633.43, 1633.7, 1724.47, 1724.63, 1835.7, 1912.2, 1912.27, 1912.43, 1954.4, 1954.67, 2005.8, 2856.87) 

=========
QMutex: destroying locked mutex
malloc(): unsorted double linked list corrupted

Thread 49 "Thread (pooled)" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffed3fff640 (LWP 23937)]
SceneSplitTask::run (this=0x5555658344c0) at ./src/jobs/scenesplittask.cpp:185
Download failed: Das Argument ist ungültig.  Continuing without source file ./obj-x86_64-linux-gnu/src/./src/jobs/scenesplittask.cpp.
185     ./src/jobs/scenesplittask.cpp: Datei oder Verzeichnis nicht gefunden.
(gdb) bt
#0  SceneSplitTask::run (this=0x5555658344c0) at ./src/jobs/scenesplittask.cpp:185
#1  0x00007ffff4ccee81 in QThreadPoolThread::run (this=0x55555ceff3f0) at thread/qthreadpool.cpp:100
#2  0x00007ffff4ccbcd1 in QThreadPrivate::start (arg=0x55555ceff3f0) at thread/qthread_unix.cpp:329
#3  0x00007ffff448784a in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#4  0x00007ffff450b2cc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

scenesplittask.cpp:185 seems indeed to be related to creating the markers, so that might be a clue.

EXPECTED RESULT

The clip markers are added at the expected position


SOFTWARE/OS VERSIONS

I am using kdenlive 22.08.2 from Debian testing, but the crash also happens with the 22.08.2 appimage.

KDE Frameworks Version: 5.98.0
Qt Version: 5.15.6 (built against 5.15.6)
ffmpeg: 5.1.2-1

ADDITIONAL INFORMATION