Trying to export fast forward 2x does not work properly

[ksaadDE]

Like in (why ever) closed issue https://github.com/OpenShot/openshot-qt/issues/2516

Issue is still existent in Version 3.1.1 (Nov/2023) @ferdnyc

Are there any workarounds?? This is a very unexpected issue.

[ferdnyc]

I responded @ https://github.com/OpenShot/openshot-qt/issues/2516#issuecomment-1826217548

But, long story short, this report is missing all of the necessary information to even attempt debugging this. Nobody will be able to fix "Trying to export fast forward 2x does not work properly". Most likely, they'll try it, and it'll work fine for them. (That's what happened in #2516.) If it's not working for YOU, you need to provide as much detail as possible about what exactly you did, for exactly what configuration, to exactly what kind of files.

[ksaadDE]

Well, I don't think there's much of a description needed. I went right-click duration speed forward 2x. Although the 4x works but not the 2x. Went to export, video is not exported with the short duration (only the original one) 🤣

If I can obtain some logs for it and publish them anonymized I would be glad to do so, I just need their location.

Thanks for your fast reply tho! :)

[Colorjet3]

Hello @ksaadDE. Please provide the following:

1. What operating system/version are you running (Windows 10 Pro? Ubuntu 22.04 lts? etc?)
2. What type of video file are you working with (.mkv? .mov? etc.).
3. How long of a video file is it?
4. Is this a single track or multi-track project? If multi-track, what is above or below this video you are applying the 2x forward effect?
5. Does this issue happen with this video file only or other video files as well?
6. Lastly, what does "...does not work properly"? For example, is it missing frames? does it stutter? etc? what actually not working with it.

This will help us to try and replicate your issue and find a solution/workaround.

[Colorjet3]

Hello @ksaadDE. Any update on this? Please see my previous request for information.

[ksaadDE]

@Colorjet3 wrote:

Hello @ksaadDE. Any update on this? Please see my previous request for information.

_

Hello, sorry I forgot abt it. A lot to do atm.

Summary: newest Linux System. Issue occurs when using the shown settings (4mbps video rate in video profile etc). The difference between my case is multi file video on one lane. I cut a lot and I used the same 2x forwarder. After export it shows the same version as in the editor, prior to the forwarding (so the long video version).

The video file length was (when the issue occurred) about 1h. After cuts and 4x forward reduced to 9 min. Though the 2x forwarder (unlike the 4x forwarder) did not work. The video remained in the same length, despite shown differently in the editor. Bitrate and Encoding of the files were all the same (recorded by same device after each other).

Disclaimer: Though in recorded attempt it is not replicable, assumingly due to a single file, single lane project. I had to quickly grab some video that is not that confidential :-D

Steps 5-1:

https://github.com/OpenShot/openshot-qt/assets/37943746/ec8bab61-762a-4455-bbea-a552167b8bab

https://github.com/OpenShot/openshot-qt/assets/37943746/278877f2-dd74-453b-b223-648981abd833

https://github.com/OpenShot/openshot-qt/assets/37943746/c60ea89b-a720-4edd-8945-2f46169c05d0

https://github.com/OpenShot/openshot-qt/assets/37943746/1961bdb9-c2e2-4f75-9935-f4f8ec278d5d

[Colorjet3]

Hello @ksaadDE. Thank you for this information. However, I am still a bit challenged trying to replicate your issue. I am not a Linux expert and been testing in Windows 11 running OpenShot version 3.1.1 latest dev daily build #11627. I did a high level testing using 2x, 4x, and 8x on a single .mp4 without issues. I also took the same .mp4 and split/cut it in the middle on the track and applied 2x to the 1st slice and 4x to the 2nd slice and Exported and no issues.

As @ferdnyc mentioned, without some detailed steps of what exactly you are doing with repeatable outcome, it is going to be difficult to debug. I really would like to replicate, as close as possible, to exactly what you are doing so we can test and debug ourselves.

Please provide the following:

1. Operating system. You say the newest Linux System. This doesn't help me. I run Oracle VM VirtualBox environment so I can install Ubuntu, Mint, Manjaro, etc. Are you running one of those distros (not sure if this is the right language)? And what version (Ubuntu 22.04, Liniux Mint 21, etc?

2. What version of OpenShot are you running (Help | About Openshot?). Please include the 3rd line of information on that screen which should include the build #.

3. I know there are a few ways to install OpenShot in the Linux environment (Flatpack, snap, AppImage, ppa). How are you installing it? This might make a difference as to which version of OpenShot you are running.

4. Please tell us exactly what steps you are performing that is causing an issue. Please don't assume and leave any details out. Something like this: a. I import one .mp4 file that is 1 hour long and another .mp4 that is 30 min. long. b. I drag the 1 hr. long clip onto Track 5. c. I drag the 30 min. onto Track 5 also snapped with the 1 hr. clip. d. I split/cut the 1 hr. clip using the "Slice All" then keep both sides. e. I apply 2x to the first slice f. ........

You get the idea. This will help in our efforts to replicate what you are experiencing.

With that said, Fast Forward functionality has been documented to be buggy (please see https://trello.com/c/baOKqVqi/81-time-fast-forward-2x-is-broken). I would like to add more details to this documented issue so we can address as many of the broken components as possible. You will not the "Steps To Reproduce" part. This is very important for the lead developer and testers like me to have to be able to replicate a problem and eventually have the developer fix it.

Thank you in advance!

A possible workaround for your issue

1. After you slice/cut your video and before applying any effects, export that clip (the slice only).
2. Now import that clip back into your project and then apply whatever effects you want.

A quick way to do this is:

1. Drag your clip onto a Track.
2. Right click and select Properties.
3. From the properties page find the Frame Number attribute. Right click the None and select Clip. This will display the Frame number on the top left corner of the "Video Preview" window.
4. Moving the Playhead around on the clip will show you the frame number. Make a note of the frame number range(s) you want to export.
5. When ready to export, change the Frame Number attribute back to None, otherwise the Frame number will show up in your Export.
6. Now click on Export | Advanced tab and change the Start and End Frame numbers as you wish and Export. Note that there is a bug in the Export interface. When you click on Export the Start Frame and End Frame revert back to the original clip. However, the Exported output is created with the actual frame number range you indicated.

[ksaadDE]

Hello @Colorjet3,

please keep in mind my time is limited. Though I'd like to add that I've installed OpenShot via RepoManager on an Arch Distro.

Like said above I run

Issue is still existent in Version 3.1.1 (Nov/2023)

of OpenShot

I actually showed the same steps I've used and the issue is not reproducible. Like you are mentioning, sometimes it is happening, sometimes not. I don't even have a slightest clue how to help you looking at the right spot in the code.

I showed a Video how I did it, just with multiple tracks back then. It caused the issue.

Regards

[Colorjet3]

No worries @ksaadDE. I will assign this issue to the lead developer so he is aware of it.

[CDixon0416]

@Colorjet3 possibly related I have seen similar behavior on Windows 10 Enterprise 10.0.19045 Build 19045 but I am losing parts of the clip when I select the fast forward 2x setting on a clip before I even get to the export.

Openshot version 3.1.1 Openshot-v3.1.1-release-1139207100dc7a-e47da46f (Official)

Steps to reproduce:

1. Grab a .mov of length X
2. Cut the video into clip sized pieces in my specific case a 10 second clip
3. From the tray right click the clip and select time, fast forward, 2x
4. Compare the original clip with the modified clip and half the content on the modified clip is missing. Specifically the second half of the clip.

I can try the work around if that would be helpful to further diagnose the problem and let you know if that's at least a viable solution while you guys continue investigating the root cause. I am using the video preview to verify the result and not the export in case that is relevant as well. Let me know otherwise I can submit a separate issue if that is preferred but I have seen your comment about fast forward still being a bit buggy so I didn't want to submit a separate issue if you were already triaging.