Hey everyone,

I would like to create a separate rendered clip showing my social media links which I can place into all of my future videos easily instead of manually adding them every time. The thing is, when I render it as an mp4, it makes the background black. How can I keep the background transparent so that I can place this clip on top of other videos? I tried rendering as an .flv but that makes the background green. When I use one of the alpha effects to select the green background, it makes it transparent, but it you can still see little bits of green around the icons and text. I would like an alternative that looks much better.

Thanks.

Alpha rendering is unfortunately not possible with Kdenlive. Kdenlive has per default a black background which gets rendered and which we cannot "remove" for rendering.

You can try with Shotcut and using either MOV (codec: qtrle) or AVI (mlt_image_format=rgb24a, pix_fmt=argb). Search for render “alpha” in Shotcut.

Hi?

is it still like this?

No, in the meantime there are 3 render profiles to render "video with alpha": Alpha VP8, Alpha VP9 and Alpha mov.

Just to note, If prores 4444 is needed here is the profile:

Code: Select all

f=mov vcodec=prores_ks qscale=%quality acodec=pcm_s16le vprofile=4444 vendor=apl0 pix_fmt=yuva444p10le mlt_image_format=rgba vf= unpremultiply=inplace=1

Were there relevant changes to this in the last year? Rendering with alpha channel worked fine last year (used 20.08.3), now I don't get the version 21.12.3 to render anything with alpha channel, which is always filled with black pixels.
Or is it just a bug?

sebabie wrote:Were there relevant changes to this in the last year? Rendering with alpha channel worked fine last year (used 20.08.3), now I don't get the version 21.12.3 to render anything with alpha channel, which is always filled with black pixels.
Or is it just a bug?

Try 22.08.0.
Lots of good things has happened in this version for alpha render. My favorite is premult options.

im going the easy way. struggled with this same problem and ended up with a simple solution. i just render the videos with social media, etc., with a green background so i can aply chroma key and voila! all solved.

Merlimau wrote:Alpha rendering is unfortunately not possible with Kdenlive. Kdenlive has per default a black background which gets rendered and which we cannot "remove" for rendering.

One could (in some cases) change the background color (into poison green f.i.) and later use the Chroma Key effect.
I sometimes do that with pre-edited vids for later usage in the master.