Old 12-21-2018, 05:09 AM   #1
Winfield
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Default Can track (video) fx only affect one track?

Hi, is it possible to have track-fx only affect items on the one track (that the effect is on) and not all the 'lower' video tacks?

The use-case here is, that I have a lot of video-text-items (on one track) that needs the same xy adjustment, that is different from the rest of video tracks.

I guess there are workarounds with rendering, or item fx, but that would loose some (much needed) flexibility later on - so I don't see that a an option here.

Thank you
W
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Old 12-21-2018, 07:19 AM   #2
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Yes, that's a big problem in my opinion. wwwmaze also posted some thought about it as this seems just not logical.
The workaround would be to lay such a track at the end of the track stack but that doesn't work for all situations. An example would be if you want blur only on one track while other tracks also are visible. This blurry track has to be the last in the stack if not everything below also will be blurred. But if one of the other track also has something special which affects the whole stack you get stuck here.

The best thing would be, if only folders would be mixing everything together while separate tracks keep their effects on their own. Or this needs kind of an divider/separator. Or there must be a separate input definition in the programming language which only allows one track input without blend possibility. For blur or something like that it would be a great option. But I have no idea how this could be done.

for the moment I can't find where wwwmaze wrote his thought about that. Will edit the post if I have found it.
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Old 12-21-2018, 02:04 PM   #3
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Yes, some of the presets implement this, but here's a preset which, if you put it last on a track, will only make the track FX used when the track has video items:
Code:
// makes track FX only used where track has video items
input = input_track(0);
input > input_next_item(0) ? input=0;

input_info(input,project_w,project_h);
gfx_blit(input);
If you're using the latest +dev builds, this can be optimized slightly:
Code:
// makes track FX only used where track has video items
input = input_track(0);
input <= input_next_item(0) ? (
  input_info(input,project_w,project_h);
  gfx_blit(input);
);
Also, you can of course put video FX on video items, or on MIDI items if you want them to operate only for that time period (they can still read video from tracks upstream etc).

Caveat: this doesn't handle being the only FX on a track properly (will figure out a workaround for that -- not that it's useful as the only FX on a track).

Last edited by Justin; 12-21-2018 at 02:30 PM. Reason: updated with helper presets
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Old 12-21-2018, 02:24 PM   #4
EpicSounds
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what would I need if I wanted the rotation part of "// Track opacity/zoom/pan"
to only apply to images, text, or lines/shapes draw by a video processor?
need some easy way to apply processing only to the output of previous video processor in same chain.
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Old 12-21-2018, 02:30 PM   #5
Justin
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Quote:
Originally Posted by EpicSounds View Post
what would I need if I wanted the rotation part of "// Track opacity/zoom/pan"
to only apply to images, text, or lines/shapes draw by a video processor?
need some easy way to apply processing only to the output of previous video processor in same chain.
Put it on a track by itself (with the previous processor), then blend it with whatever else as you like from another track?
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Old 12-21-2018, 05:08 PM   #6
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Quote:
Originally Posted by Justin View Post
Put it on a track by itself (with the previous processor), then blend it with whatever else as you like from another track?
it rotates the background video as well.
the text and lines are made in video processor. its even worse if you want the drawing to rotate different from the text.

Works differently with image files, pretty much fine.

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Old 12-21-2018, 06:05 PM   #7
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I think the problem is that you want to make a mask, transform it, then combine it with something else. You can definitely do this, but it takes a bit more work.

(these all require a recent +dev build, though most of the techniques can be used in 5.965 too)

Here's one way to do it:

https://1014.org/_/overlaytransform.rpp

Track 2 has a video.
Track 1 has a green background generator => text overlay => track opacity/zoom/pan (modified to fill background with green rather than black, see comment inside it) => Chroma-key, which combines track 2 with track 1.

This is pretty fast but doesn't allow partial transparency.

Here's another way, which is probably about as fast but requires going to RGBA:

https://1014.org/_/overlaytransform2.rpp

Track 2 has a video
Track 1 has a black background generator => text overlay => track opacity/zoom/pan => custom RGBA red to alpha channel converter => image overlay

This allows partial transparency, but because red is copied to alpha, you are limited in what colors are available to you in your overlay image. You could tweak which channel is used in order to allow some different combinations, but it's not ideal either.
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Old 12-21-2018, 06:47 PM   #8
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Edit: extending RGBA mode to give more control over RGBA alpha channel writing. This will give the best performance for RGBA and also full color.

In today's build you will be able to use:

https://1014.org/_/overlaytransform3.rpp

Some of the various presets may need to be extended to be alpha-channel aware though...

Last edited by Justin; 12-21-2018 at 07:00 PM.
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Old 12-21-2018, 07:29 PM   #9
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thanks for looking into this so quickly.

btw for text I usually have the fx chain on MIDI items
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