Confirmed on mine, as well. Using 33 h.264 video clips, interleaved with 33 JPEG images, using transition + pan&zoom on each JPEG. Looks fine in timeline, but the rendered file shows the transition to and from a solid white background.

Kdenlive 16.12.1.
Windows 10 x64, Core i7, 16 GB RAM.

Workaround I read is to use PNG instead of JPEG. Just sucks that I have to convert all of my images and replace them in the timeline. But I'll give it a try.

Kdenlive 16.12.3, UbuntuStudio 17.04 amd64, JPG mixed with DV and .MP4 source videos to .mp4 works fine. Windows or kdenlive version problem?

Found "Fix various aspect ratio issues and transparency of composite transition in some cases" fix here:  https://kdenlive.org/2017/02/kdenlive-16-12-2-released/

17.04 Windows version seems to be available: https://files.kde.org/kdenlive/release/Kdenlive-17.04.0-2-w64.7z.mirrorlist

Jacob: you could replace .JPEG with .PNG with Notepad++ editing .kdenlive file (backup before).

Cyril, thanks for the info. Since encountering this bug, I realized I should just get back into the Linux world for a bit anyway, so I just imported my project into Kdenlive in Linux and carried on without the problem. For the past several years I've been using FreeBSD more than Linux, but unfortunately the Kdenlive package in FreeBSD is hopelessly outdated. :-)

There is a known rendering bug of jpg's in the windows version. Note that the windows version is in an alpha state still.

(In reply to Santiao from comment #0)
> I am trying to define a showslide  clip but i cannot do it.
> I cannot render a clip that contains jpg images with transitions and
> effects. The mp4 file resulting is all White and doesn t contain image.
> I m using the Windows versión of Kdenlive.
> Thanks

I believe that adding a slideshow clip is impossible for now (if you tried the: Add SlideShow Clip option). As for getting a white background, I encountered the same problem. Sometimes it would render some images (in .png) and not others. Try to copy the ffmpeg 3.2.4 bin folder files in the main folder of kdenlive, it solved it for me. There's a youtube video that shows different image formats being used and rendered in .mp4 format perfectly: https://www.youtube.com/watch?v=bQfUXTXzSkk

Also see https://bugs.kde.org/show_bug.cgi?id=376464 which tells about the same bug. It's not only Windows, it is also the linux version. I don't know when it started, which Kdenlive version, but suddenly it didn't work anymore. I now have a huge project which I can't finish becuase of it. Converting all images from jpg to png is possible but a lot of extra work.
Is it possible somebody takes a look at this? Thank you.

(In reply to DeMus from comment #6)
> Also see https://bugs.kde.org/show_bug.cgi?id=376464 which tells about the
> same bug. It's not only Windows, it is also the linux version. I don't know
> when it started, which Kdenlive version, but suddenly it didn't work
> anymore. I now have a huge project which I can't finish becuase of it.
> Converting all images from jpg to png is possible but a lot of extra work.
> Is it possible somebody takes a look at this? Thank you.

I am using the linux version and don't have any issues. Afaik it is a windows only problem... 

Which versions of MLT and Kdenlive are you using? How did you install them?

This is a Windows specific issue. On linux, slideshow clips using mime type are created with an url like :

Picture/.all.jpg
(will take all jpg images in the Pictures folder

But on Windows, the url needs to be:
Picture\/.all.jpg

So we need to adjust the code to append a backslash to the path (and

This is a Windows specific issue. On linux, slideshow clips using mime type are created with an url like :

Picture/.all.jpg
(will take all jpg images in the Pictures folder

But on Windows, the url needs to be:
Picture\/.all.jpg

So we need to adjust the code to append a backslash to the path (and adjust a few places where we check for ".all." to identify mime slideshows.

Something like:

#ifdef Q_OS_WIN
    folder.append(QDir::separator());
#endif

in line 423 of src/project/dialogs/slideshowclip.cpp should allow the creation of slideshow clips

*** Bug 376860 has been marked as a duplicate of this bug. ***

created https://phabricator.kde.org/T9992

Workaround see here: Bug 404185

Hello everyone!
Can someone try and report if that workaround is working?:
Problem: If you added your photos, and after rendering the place of the image is the video is blank.
Solution (maybe?): 
1) Rename your photos to only sequence numbers, and the first file should be full zeros. For example, if you have 1001-9999 pcs of photos, rename the files like this: 0000.jpg; 0001.jpg; 0002.jpg etc... (of course, if you have less than 100 pcs of photos, you can use three character long file names)
2) Add a slideshow, use filename pattern, select the first image in the sequence.
3) Add the slideshow clip to the timeline, and render it.
In this case the slideshow / time-lapse will be rendered correctly.

If I start the image sequence with another file name then full zeros (01 or 001 or 0001...) then the image sequence is added to the Project Bin and the timeline, it plays correctly in Kdenlive, but when I render it, the video shows "INVALID" text with a black background.

May I ask you to use this workaround to create your image sequence and report if it has solved the problem?

SlideShow on Windows is solved: https://invent.kde.org/kde/kdenlive/commit/7db21278c5a38e4187abf48a9901d624cfb0466f will come with 19.04.2.

JPG rendering is fixed with 19.04.0