Hangs when drag-n-drop many to timeline

Hi guys

Shotcut all of sudden freezes and crashes for last few days, I don’t what is wrong, as soon as I put videos onto the timeline, shotcut crash.

I have uninstalled and reinstalled to the latest version of shotcut, updated all drivers for laptop and graphic card.

I tried Openshot to see if it is my computer’s issue, I have no issues with Openshot.

please watch the video and help me identify the issue. I can not live without Shotcut.

I have legion 5 pro with 3070 on windows 10

thanks you

Can’t see what goes on, it is just to small, you should decrease the resolutions before making a screencast.
Try to disable any kind of HW acceleration in shotcut, try testing on off your source files at a time, and post the properties of the source files (before adding them to the timeline)
Video with variable frame rates can cause a lot of problems for a video editor.

how do I disable HW acceleration in Shotcut?

What is your Shotcut version? Upgrade to the latest version, which is 22.01 if not the latest.
Try reboot if you have not yet.
Try something simpler and different things to see what is wrong. For example, open one video file using File > Open instead of drag-drop. Does it play? Next, add it to the timeline.

Yes I have upgraded to the latest version as mention is my very first post. I obviously had restarted my computer many times after installing latest version of shotcut and all the pertinent drivers.

One by one works, drag and drop many freezes shotcut.

I am still trying to reproduce it without success yet. Do you have Settings > Realtime turned on? If not, turn it on, restart, and try again.

Do you have proxy enabled (Settings → Proxy → Use proxy)? You have a really power hungry GPU so the quick conversion alone could raise the temps a ton.
Keep task manager in the Performance tab open while re-doing this. Which item goes to 100%? Or at least jumps up when you drop the video on timeline.
Also try with some other video, not OBS recorded, maybe you have some weird settings there which Shotcut does’t like, try something like a quick 1 min video from your phone.

You left Shotcut in Automatic Video Mode. When Automatic is left, Shotcut will match the first file opened and make a video mode for that 1st file. If your file is 4k 24fps, it will make such a video mode.

In Openshot you have a project at 720p 30fps, yet you exported at 4k 24fps from that 720 video mode. Not sure how that video turned out.
2022-03-19_17-14-28

You dropped all 4 videos into Shotcut’s timeline at once.
With Openshot, you placed 1 video at a time in the timeline.

Yeah, it is a weird problem he is having. I was able to drag 36 videos totaling 38.5 hours from file explorer to Shotcut playlist, select all in playlist and drag to timeline without a problem. It got slow, of course, but it shows a progress dialog when adding to the playlist or timeline takes over 2 seconds, which it did. It did not in his video, which is curious. I wonder if some of the videos are recorded in a way that Shotcut does not like as we have seen this with OBS and other screen recordings in the past. For example, not only variable frame rate but also sometimes the duration is foul and is read by FFmpeg as very long.
Please open one of the OBS recordings, view Properties, make a screen grab of just that part, and paste here. Thanks

Another thing to try: reboot, reinstall Shotcut before anything else, and turn on the checkbox to remove Shotcut’s settings from the registry in the installer.

Realtime was turned on.
Proxy mode was turned off.

I made a fairer comparison between Shotcut and Davinci Resolve this time. I drag all videos at the same time to the timeline for both Shotcut and Davinci Resolve.

DaVinci Resolve is stable as where Shotcut still crashes. Shotcut is only stable if I drag one video at a time to the timeline.

Followed this instruction to the letter. Still crashes using the same four files in the above video (Shotcut vs. Davinci Resolve Stability)

I randomly chose 4 1080p movies (I don’t have any 1+ hour clip ready) and dragged them to the timeline and while it doesn’t hang, it seems shotcut is a bit slow trying to fully read the 4 files from disk (I assume to analyze them, draw the waveform, etc).
So what I suggest is to try to wait 2-3 minutes as the app needs to read 22GB in your case. For me this operation used 25% cpu (but I am using a desktop and temp is not an issue) and it lowered down to 9% (so basically only 1 core was used at 100%, rest barely) if I disabled waveforms in the timeline.
If I am right and it’s waiting for disk operation, you can see this in task manager performance tab, the S: drive would show 100% (in my case the fiels were on a NAS and saw ~700mbps read for a few minutes then everything was calm and stable).

Pretty sure that is not the case, just checked in that project setting, the timeline resolution is actually 2160p !

So I presume Davinci Resolve did not crash at 4K but Shotcut crashes at 1440p since project was using automatic.

Can anyone know both software confirm if that is the case?

I was wrong about the top presets. Clearly Resolve is way out of my knowledge base, nor anything I care to learn about.

Was trying to recreate the same thing you did, and was looking at your videos trying to figure out your source file specifications, otherwise I probably would not have watched them.

I’ll keep watching this thread to see if you find a solution.

Moving to DaVinci Resolve fulltime now. This is the only solution.

Davinci Resolve is just to much better than Shotcut in terms of functionality, stability and community support and tutorial videos.

Best of luck to Shotcut.