Bug 364583

Summary:	Composition effect: Using the zoom produces black outlines
Product:	[Applications] kdenlive	Reporter:	Stefan Naumann <me>
Component:	Video Effects & Transitions	Assignee:	Vincent PINON <vpinon>
Status:	RESOLVED FIXED
Severity:	minor	CC:	drrn, wegwerf-1-2-3
Priority:	NOR
Version:	16.04.0
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
URL:	https://www.youtube.com/watch?v=pGDym-_Dv70
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Bug Position and Zoom

Description Stefan Naumann 2016-06-21 09:02:32 UTC

The Attached youtube-video shows the behaviour well, at around second 6 I zoomed a title into the image, when it becomes smaller, than the video-frame itself, there are black-borders especially on the right. 

Reproducible: Didn't try

Steps to Reproduce:
1. Create a Title
2. Use the Composite-effect for displaying
3. Set the zoom-factor as decreasing (using keyframes)

Actual Results:  
Black outlines of the title-frame (not title-text) should appear.

Expected Results:  
No black outlines, just the text is shown. 

Work-around would be not to use the zoom-function. The video has been rendered with 16.04.2

Comment 1 Vincent PINON 2016-08-09 09:57:57 UTC

Sorry I can't see what you are speaking about in the video (oettingergames / Alan Wake?).
For composition, we use transitions rather than filters. Is it what you are actually doing?
And for better precision we recommend to use Affine (or cairoblend) rather than composite.

Comment 2 Wegwerf 2016-08-09 14:59:56 UTC

I can't see it either, at least not on my tablet. Are these rather thin black lines, as opposed to thicker borders? I noticed them when using then Affine transition in some border cases; Vincent, wasn't there some Affine fix in MLT or something in frei0r related to that some time ago?

Comment 3 Stefan Naumann 2016-08-09 15:12:07 UTC

There are rather thin black lines around the edges of the virtual text-layer which is shrinking in size. These black lines appear not directly at the text, but the edge of the layer.

Affine is (or at least was in older versions) way heavier on cpu-power and therefore rendering-time, than composite.

Comment 4 Wegwerf 2016-08-09 15:19:53 UTC

Sounds like the issue I also saw in one of my projects. 

Re: affine ... it is computationally more intensive; new "Composite and transform" may give better rendering performance,  but then, we have now timeline preview rendering in the current beta.

Re: compose ... downside is luma bleed, which is a constant headache; upside is wipe support, which I still lack for the new C+T transition.

Comment 5 Dany 2016-09-15 23:22:12 UTC

Created attachment 101108 [details]
Bug Position and Zoom

Same problem for me. 
"Add effect -> Crop and Trasform -> Position and Zoom" create a white vertical line outside the clip's area (and maybe little white dots too along lower line).

Comment 6 Wegwerf 2016-09-16 13:54:31 UTC

Which version of frei0r are you using?

Comment 7 Dany 2016-09-16 14:09:13 UTC

(In reply to Wegwerf from comment #6)
> Which version of frei0r are you using?

The one I find in Mint 18 (Cinnamon) repository.  They write 1.5+git201604011602-0xenial1
Yesterday I opened a new bug report with ID 368875.

Comment 8 Wegwerf 2016-10-08 16:24:29 UTC

I cannot reproduce with recent frei0r (1.5+git201609111432) and MLT (6.3.0+git201609270616~ubuntu16.04.1) from recent git master Kdenlive ppa, using an older project where I know that it has exhibited the rendering issues you've reported here. This seems to have been fixed; please check with your distribution/package providers.