Jonray's Diagonal Swipe Transition made into a Filter

Nice work guys, will be giving it a test drive.

Interesting - I just did a test and as you can see there are 2 glitches, appearing at the beginning of transitions #2 and #4 (both of which are set to “reverse”). Transitions #1 and #3 seem to work perfectly (of course these are not set to “reverse”):

https://streamable.com/v2o46

So then I made a screen capture of my SC project, advancing frame by frame. A full frame of the clip on V2 seems to be added momentarily, creating the glitch.


https://streamable.com/u4b26

@elusien - how odd that it’s not happening to you. I’m using “alt+right arrow” to locate the split points, then splitting with S (or O (outpoint) when appropriate), so I’d have thought the clips are being cut at precisely the correct positions.

Not sure whether it’s a “Shotcut thing” or something to do with the JR transition itself.

Thanks, would love to see any demos you come up with!

(Only if you have the time/inclination of course - no pressure from me!) :smiley:

What is the minimum version of SC needed?
I’m using 19.04 on this mac and all it does is create a white frame which obscures the video.

Hi @paul2, did you follow the instructions for SC versions previous to 19.06 on elusien’s website here?

I’m using 19.06.15.

Wow, those are a lot of steps in total.
The filter does give more flexibility but using a pre-made wipe is a lot simpler.

First video clip on V1
Second video clip on V2
Transition on V3

I’ve looked more closely at this and have managed to see the glitch in the “preview” window, but only the first time it goes through the split. Every time after that the glitch does not appear until you reload the MLT file and it happens again, but only the first time through the split.

I have a good idea why it’s happening (it is in the javascript code) and will try to fix it. I might not have time today (taking neighbours to the airport), but hopefully I’ll have a fix by tomorrow night.

Well, yes, @paul2 - it does look a bit complex and daunting!
However, in its defence the process looks a more complex process on paper than it actually is in practice, and for me it is worth the effort to achieve the desired effect and for the flexibility of angle-colour/speed etc.

Plus, my wipe design has a complication in that clip1 has to be gradually replaced by clip 2 as the diagonal line passes through, which is hard to achieve with a pre-made transition.

I do like your transition especially the green/red wipe in your demo 1. How does that work (is it a green screen mp4?), and did you make it yourself?

@elusien, great, you are darned clever!! (I have no idea how you got this filter to work and I am in awe of your programming skills!!) Thank you, no rush from me…

There are actually two ways to do it:

  1. Chroma key if the original video does not have an alpha channel
  2. If the video was exported as an Apple Animation in a mov then it supports alpha.

That specific transition I did not make.
The editors use Ross Expression to make their own transitions.
It’s a commercial package but there are other open source alternatives like Synfig ans Pencil 2D
which although aimed more at cartoons/animation, they can be used to make transistions.
In Pencil 2D, just use the “Camera Layer” to move things like diagonals around.

Neither Synfig nor Pencil 2D support exporting to Apple Animation, but you can export to png, bring it into SC and from there export with alpha in a mov then bring it back and use as a transition.
Or of course just use a chroma key.
Bit more of a hassle than Xpression but soooooo much cheaper.

Just back from Paphos Airport. On the 1-hour trip in the dark I got to thinking about the problem and fixed it as soon as I got home. It had to do with the opacity setting for the Chroma div at time 0.0 when the “reverse” option is specified. It was set to zero for the very first frame of such clips, so the 1st frame displayed was that on V1, not V2!

I have updated the ZIP file on the webpage, but if you want to edit the index.html file itself you can. The “if” clause at line 163 should read:

if (params.chroma || params.mask) {
	html.chroma.style.display = 'block';
	html.chroma.style.opacity = 1;	// Needed to stop a "glitch" when the "reverse" option is specified.
	for (i =0; i < 4; i++) { html[divs[i]].style.display = 'none'; }
} else {
	html.chroma.style.display = 'none';
	html.chroma.style.opacity = 0;
	for (i =0; i < 4; i++) { html[divs[i]].style.display = 'block'; }
}

Brilliant! Thank you for your detective work :smile: Just shows how a erroneous pesky 0 or 1 can cause problems!
New zip downloaded, will give it a test run if I can grab time later.

Hi @paul2, thank you so much for this information. I’ll definitely look into it. And the transition in your demo #1 has given me a few creative ides - watch this space…:smile:

Hi @elusien, sorry to report this but I’m still getting glitches, even with the new revised JRtransition file.

See this demo:

https://streamable.com/38cu3

This time the glitch appears as a full frame of the clip on V1 when the filter is applied to V2 without “reverse”- ie the other way round to the earlier problem. So there are 2 glitches in the above demo, at transitions #1 and #3.

My timeline is as follows:

Can you replicate this?

Mea Culpa,

I only tested the other transition (“reverse chroma”). The fix did in fact introduce the problem you are seeing. Thanks for spotting it and letting me know.

THE FIX is to change line 165 to say:

if (params.reverse) { html.chroma.style.opacity = 1; }	// Needed to stop a "glitch" when the "reverse" option is specified.

i.e. only set the opacity to 1 if you have the “reverse” option specified.

I have updated the ZIP file on the website.

Hey hey hey - it now works like a dream!! Thanks @elusien! :smile::smile:

https://streamable.com/avi4n

That does look nice, well done guys.

Thank you!

I just made this quick tutorial for the JR filter. I didn’t have time to add a spoken commentary. @elusien, please let me know if there are any inaccuracies/ errors/omissions, if you have a spare moment to take a look.

https://streamable.com/svvyp

Brillian:. thanks for doing this.

I would like to do more tutorials, but I have a bit less time than usual to do things with Shotcut at the moment as I have family visiting.

@jonray

Very nice, well done.
Also been watching your html tuts, nice clear voice.
Reminds of the voice overs on Open University.

Thanks again for the work done.

But In fact I tend to prefer the GL transitions : http://www.elusien.co.uk/shotcut/gl-transitions/index.html

Are there PROS using stuffs transformed as filter (smoother… ) ?