I'm using Kdenlive 19.04.1 on windows 10 and I have set up my zone for rendering using the I and O method and it shows up blue on the preview monitor. When I try and render the clip, it renders fine but if the movie is 4 mins long and the timeline in the app is 18 mins long total the output movie is 4 mins of my movie and 14 mins of a black screen.

Is there something I'm doing wrong? I've tried rending using full project and selected zone with only the 4 mins selected with no luck. I tried it on two projects and both same outcomes except the other one had a 21 min timeline so the output was 4 mins of the movie and 17 mins of a black screen.

Is there a way to shrink the timeline after editing to only be as long as the movie?

If you enable in the render dialog „selected zone” it should render the zone determined in the timeline only.

Which render format do you use (mp4?).

Hi,

Yes I tried selecting the selection zone with the correct portions of the timeline selected and it still rendered the whole thing. I'm rendering in MPEG-2 as MP4 only renders sound when I render the movie...no video is rendered...which is another issue but MPEG-2 works fine except the excess blank screen at the end.

I think I figured out the issue to both problems, I found on another thread for the video issue this document:

https://bugsfiles.kde.org/attachment.cgi?id=108162

I downloaded the latest MP4 codecs and installed as per the document, I think my main issue was that the environment was set up incorrectly. All the files were referencing old locations that didn't exist anymore.

I got those all changed and now it works properly and even MP4 works correctly.

Thanks for your help.

I get the same problem with Kdenlive on Linux.
My Video is ~3mins long but the rendered video is 20 minutes like the whole timeline.
Already set in and out-points and rendering only selected zone, but still 17 minutes additional black screen in the end.
How can i get rid of this, i'm rendiering with the default mp4/h264 1080p profile?

Please help,
pappl

pappl wrote:I get the same problem with Kdenlive on Linux.
My Video is ~3mins long but the rendered video is 20 minutes like the whole timeline.
Already set in and out-points and rendering only selected zone, but still 17 minutes additional black screen in the end.
How can i get rid of this, i'm rendiering with the default mp4/h264 1080p profile?

Please help,
pappl

+1 ... exactly the same problem on Linux.

zakazak wrote:

pappl wrote:I get the same problem with Kdenlive on Linux.
My Video is ~3mins long but the rendered video is 20 minutes like the whole timeline.
Already set in and out-points and rendering only selected zone, but still 17 minutes additional black screen in the end.
How can i get rid of this, i'm rendiering with the default mp4/h264 1080p profile?

Please help,
pappl

+1 ... exactly the same problem on Linux.

Strange there is no way to trim the timeline length after last clip. This would solve the problem as a workaround.

Here is a workaround to trim the last minutes of the rendered video without reencoding in 1 second.

Open terminal and type:

Code: Select all

ffmpeg -ss 00:00:00 -t 00:05:33 -i "PATH TO LONG VIDEO.mp4" -acodec copy -vcodec copy -movflags faststart "PATH TO NEW TRIMMED VIDEO.mp4"

Edit the time after -t to your need (HH:MM:SS), in this case 5min 33sec

Just wanted to point that I've discovered what causing it.
There is an option "Use GPU processing (Movit library)" in the Playback section of settings. It it's checked - you'll have those issues with rendering tens of minutes of empty screen even when trying to render only selected zone.

https://invent.kde.org/kde/kdenlive/issues/221

a@pavel.bz wrote:Just wanted to point that I've discovered what causing it.
There is an option "Use GPU processing (Movit library)" in the Playback section of settings. It it's checked - you'll have those issues with rendering tens of minutes of empty screen even when trying to render only selected zone.

https://invent.kde.org/kde/kdenlive/issues/221

I will not disable GPU acceleration since this is a standard feature of every video editing software since decades.

I'll use quick ffmpeg trimming after rendering in terminal until a fix is released. This will save 30 minutes for every video GPU rendered.
I added faststart to the trimming code to make videos youtube and streaming compatible:

Code: Select all

ffmpeg -ss 00:00:00 -t 00:07:44 -i "PATH TO LONG VIDEO.mp4" -acodec copy -vcodec copy -movflags faststart "PATH TO NEW TRIMMED VIDEO.mp4"

Will trim at 7min 44sec and leave start at 00h00min00secs.

pappl

Edit: Changed code to avoid video curruption.

Thanks for your report. This was in fact an issue in MLT that was fixed a few days ago. I will upload a new 19.04.2d AppImage in a few hours with the fix.

jbm wrote:Thanks for your report. This was in fact an issue in MLT that was fixed a few days ago. I will upload a new 19.04.2d AppImage in a few hours with the fix.

But the appimage does not allow enabling GPU playback so how do we verify ?
Any hopes of getting the fix in the native package via the ppa repo and/or the flatpak ?

Seems like I found a workaround...

1. I upgraded the recently released Shotcut 19.06.
2. In kdenlive, instead of using "render to file", use "Generate script".
3. Run that script from command line. eg: /home/user1/software/Shotcut/Shotcut.app/melt -progress ./kdenlive-renderqueue/renderscript.mlt

No more huge blank video in the end !
Finally have GPU playback+effects as well as GPU accelerated rendering.
Seeing 100%GPU usage. CPU usage has dropped to half its previous value !

I have got this problem too, still, even with the "Use GPU processing (Movit library)" turned OFF ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
Ubuntu KDE 18, Kdenlive 19.12.1
How can it be that earlier version of 18.Kdenlive did NOT do this with exactly the same options on the same computer? I have just upgraded kdenlive so I only got this problem from a few hours since (and i did NOT changed anything else in my computer).

Please official kdenlive, FIX THIS BUG ! ! ! ! ! ! ! !

Thanks

Please don't panic and shout at people to get help.
You can download any release AppImage here to finish your work:
https://files.kde.org/kdenlive/release/
And if you could identify which kind of clip/effect/transition fails, that could help.