Compositor: 'invert' option of the 'Stabilize 2D' node does not work correctly #79563

New Issue

Paul Brunt · 2020-08-05T18:05:07+02:00

Paul Brunt commented

2020-08-05 18:05:07 +02:00

System Information
Operating system: Win10 64
Graphics card: 3070

Blender Version
Broken: 2.83
Worked: N/A

Short description of error
As indicated in the tip and in the manual, the invert option of the Stabilize2D node kind of undoes the stabilization effect and "reintroduces montion to the frame".
But in practice, when undoing the stabilization, while the rotation and scale appear to be correct, the image position is incorrect.

Exact steps for others to reproduce the error

Open the attached file
Switch between frames 1, 2 and 3 to see a correct stabilization
Unmute the Stabilize 2D node that has the invert option enabled
Switch frames again and see that the image position is not corrected
The Transform node can help you see what's going on.
Stabilize2DBug.blend

**System Information** Operating system: Win10 64 Graphics card: 3070 **Blender Version** Broken: 2.83 Worked: N/A **Short description of error** As indicated in the tip and in the manual, the `invert` option of the `Stabilize2D` node kind of undoes the stabilization effect and "reintroduces montion to the frame". But in practice, when undoing the stabilization, while the rotation and scale appear to be correct, the image position is incorrect. **Exact steps for others to reproduce the error** - Open the attached file - Switch between frames 1, 2 and 3 to see a correct stabilization - Unmute the `Stabilize 2D` node that has the `invert` option enabled - Switch frames again and see that the image position is not corrected The Transform node can help you see what's going on. [Stabilize2DBug.blend](https://archive.blender.org/developer/F8754029/Stabilize2DBug.blend)

Paul Brunt commented

2020-08-05 18:05:07 +02:00

Added subscriber: @supereggbert

Richard Antalik commented

2020-08-06 04:52:08 +02:00

Added subscriber: @iss

Richard Antalik commented

2020-08-06 04:52:08 +02:00

It would definitely help if you can provide example file. I would recommend to rendering very simple and short video so that files provided would illustrate the issue clearly. Then simply upload video same way as you upload .blend file.

Paul Brunt commented

2020-08-06 07:29:40 +02:00

Here you go hopefully it helps Stabilize2D.zip

Here you go hopefully it helps [Stabilize2D.zip](https://archive.blender.org/developer/F8751060/Stabilize2D.zip)

Germano Cavalcante changed title from ~~Stabilize2d Comp Node Invert~~ to Compositor: 'invert' option of the 'Stabilize 2D' node does not work correctly

2020-08-07 03:46:50 +02:00

Germano Cavalcante commented

2020-08-07 03:46:50 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Germano Cavalcante commented

2020-08-07 03:49:44 +02:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2020-08-07 03:49:44 +02:00

Thanks for the file.
It really helps to identify the bug.

Thanks for the file. It really helps to identify the bug.

Richard Antalik commented

2020-08-07 05:14:48 +02:00

Changed status from 'Confirmed' to: 'Archived'

Richard Antalik closed this issue

2020-08-07 05:14:48 +02:00

Richard Antalik self-assigned this 2020-08-07 05:14:48 +02:00

Richard Antalik commented

2020-08-07 05:14:48 +02:00

File definitely helped.

Looking at code, this doesn't look like bug. Invert property does exactly what it says in manual https://docs.blender.org/manual/en/dev/compositing/types/distort/stabilize_2d.html

Issue here is, that image is scaled, translated and rotated with reference to center of the image. This operation is performed again with inverse values, but reference point is still in the center of image. I think reversing order doesn't apply here really.

This could be resolved by passing reference to new center of image, but I am not aware how this would be useful in real life application.

File definitely helped. Looking at code, this doesn't look like bug. Invert property does _exactly_ what it says in manual https://docs.blender.org/manual/en/dev/compositing/types/distort/stabilize_2d.html Issue here is, that image is scaled, translated and rotated with reference to center of the image. This operation is performed again with inverse values, but reference point is still in the center of image. I think reversing order doesn't apply here really. This could be resolved by passing reference to new center of image, but I am not aware how this would be useful in real life application.

Paul Brunt commented

2020-08-07 10:22:44 +02:00

Thanks for the clarification.

Just as an example of a real life application, I was trying to overlay some cartoon sun glasses on a face and wanted them to track the eyes of a person (position/scale/rotation), something you can typically do with reverse stabilisation.

I think the manual does indicate a bug, it says if "no invert" move up by 5 units then "invert" moves down by 5 units. That isn't the case as in the example blend (previously submitted) you can see the number of units that where moved up with the stabalize doesn't equal the number of units moved down by the invert.

You really shouldn't need to add any additional reference to new center of image as it can be done with some maths and transform nodes (see attached blend with node setup). All that needs to happen is that the order of operation needs to be reversed, ie for stabilize then invert the list of operations are currently:
[Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( unscale -> unrotate -> untranslate )
but they should be:
[Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( untranslate -> unrotate -> unscale )
The change won't effect anything without scale and rotation but will make the invert actually useful for case where scale and rotation are used.

Hopefully, the attached blend is helpful in illustrating the problem.
Stabilize2Dfix.zip

Thanks for the clarification. Just as an example of a real life application, I was trying to overlay some cartoon sun glasses on a face and wanted them to track the eyes of a person (position/scale/rotation), something you can typically do with reverse stabilisation. I think the manual does indicate a bug, it says if "no invert" move up by 5 units then "invert" moves down by 5 units. That isn't the case as in the example blend (previously submitted) you can see the number of units that where moved up with the stabalize doesn't equal the number of units moved down by the invert. You really shouldn't need to add any additional reference to new center of image as it can be done with some maths and transform nodes (see attached blend with node setup). All that needs to happen is that the order of operation needs to be reversed, ie for stabilize then invert the list of operations are currently: [Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( unscale -> unrotate -> untranslate ) but they should be: [Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( untranslate -> unrotate -> unscale ) The change won't effect anything without scale and rotation but will make the invert actually useful for case where scale and rotation are used. Hopefully, the attached blend is helpful in illustrating the problem. [Stabilize2Dfix.zip](https://archive.blender.org/developer/F8754985/Stabilize2Dfix.zip)

Richard Antalik commented

2020-08-07 12:21:08 +02:00

Changed status from 'Archived' to: 'Needs Triage'

Richard Antalik reopened this issue

2020-08-07 12:21:08 +02:00

Richard Antalik commented

2020-08-07 12:21:08 +02:00

In #79563#992436, @supereggbert wrote:
Thanks for the clarification.

Just as an example of a real life application, I was trying to overlay some cartoon sun glasses on a face and wanted them to track the eyes of a person (position/scale/rotation), something you can typically do with reverse stabilisation.

I think the manual does indicate a bug, it says if "no invert" move up by 5 units then "invert" moves down by 5 units. That isn't the case as in the example blend (previously submitted) you can see the number of units that where moved up with the stabalize doesn't equal the number of units moved down by the invert.

You really shouldn't need to add any additional reference to new center of image as it can be done with some maths and transform nodes (see attached blend with node setup). All that needs to happen is that the order of operation needs to be reversed, ie for stabilize then invert the list of operations are currently:
[Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( unscale -> unrotate -> untranslate )
but they should be:
[Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( untranslate -> unrotate -> unscale )
The change won't effect anything without scale and rotation but will make the invert actually useful for case where scale and rotation are used.

Hopefully, the attached blend is helpful in illustrating the problem.
Stabilize2Dfix.zip

I closed this after @mano-wii confirmed without noticing that, so I should really reopen this.

Reversing order would work. I stand corrected. But my question was rather why wouldn't you just use original images. This is solely demonstration of bug not real world use case am I correct?

> In #79563#992436, @supereggbert wrote: > Thanks for the clarification. > > Just as an example of a real life application, I was trying to overlay some cartoon sun glasses on a face and wanted them to track the eyes of a person (position/scale/rotation), something you can typically do with reverse stabilisation. > > I think the manual does indicate a bug, it says if "no invert" move up by 5 units then "invert" moves down by 5 units. That isn't the case as in the example blend (previously submitted) you can see the number of units that where moved up with the stabalize doesn't equal the number of units moved down by the invert. > > You really shouldn't need to add any additional reference to new center of image as it can be done with some maths and transform nodes (see attached blend with node setup). All that needs to happen is that the order of operation needs to be reversed, ie for stabilize then invert the list of operations are currently: > [Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( unscale -> unrotate -> untranslate ) > but they should be: > [Stabilize2d]( scale -> rotate -> translate ) -> [Stabilize2d Invert]( untranslate -> unrotate -> unscale ) > The change won't effect anything without scale and rotation but will make the invert actually useful for case where scale and rotation are used. > > Hopefully, the attached blend is helpful in illustrating the problem. > [Stabilize2Dfix.zip](https://archive.blender.org/developer/F8754985/Stabilize2Dfix.zip) I closed this after @mano-wii confirmed without noticing that, so I should really reopen this. Reversing order would work. I stand corrected. But my question was rather why wouldn't you just use original images. This is solely demonstration of bug not real world use case am I correct?

Richard Antalik commented

2020-08-07 12:48:12 +02:00

Added subscriber: @Sergey

Richard Antalik commented

2020-08-07 12:48:12 +02:00

I did this reverse stabilization trick and you are correct, it doesn't work as expected with stabilize 2D node. I am not sure whether this is intentional or not. I will need info from @sergey.

You can switch between stabilize 2D and desired behavior nodes in this file to see issue clearly:
Stabilize2DFix.zip

I did this reverse stabilization trick and you are correct, it doesn't work as expected with stabilize 2D node. I am not sure whether this is intentional or not. I will need info from @sergey. You can switch between stabilize 2D and desired behavior nodes in this file to see issue clearly: [Stabilize2DFix.zip](https://archive.blender.org/developer/F8755387/Stabilize2DFix.zip)

Paul Brunt commented

2020-08-07 13:01:25 +02:00

yep, the included files are just to show the bug in cleanest way I could. You're right it would be ridiculous to actually do what was in the example, so I can see the confusion.

Sergey Sharybin commented

2020-08-07 15:43:56 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Sergey Sharybin commented

2020-08-07 15:43:56 +02:00

I think there is even simpler possible demo case: 2D Stabilize -> Inevrted 2D Stabilize. That is supposed to give original image (I think even the black "padding" wouldn't be expected, but my memories are a bit rusty).
Since the Stabilize work, and manual inverted stabilize work, i think it's the wrong order of operations in the Stabilize2dNode::convertToOperations for the invert case.

I think there is even simpler possible demo case: 2D Stabilize -> Inevrted 2D Stabilize. That is supposed to give original image (I think even the black "padding" wouldn't be expected, but my memories are a bit rusty). Since the Stabilize work, and manual inverted stabilize work, i think it's the wrong order of operations in the `Stabilize2dNode::convertToOperations` for the `invert` case.

Sergey Sharybin commented

2020-08-07 15:44:37 +02:00

@iss, Just noticed the task is assigned to you. Are you looking into it? Otherwise i can do it next week.

Richard Antalik removed their assignment 2020-08-08 00:33:58 +02:00

Sergey Sharybin self-assigned this 2020-08-10 09:33:25 +02:00

blender-admin commented

2020-08-10 16:12:54 +02:00

This issue was referenced by eca062b9cb

This issue was referenced by eca062b9cbea5b5e30345ae5de1cf5a089003a19

Sergey Sharybin commented

2020-08-11 17:52:28 +02:00

Changed status from 'Confirmed' to: 'Resolved'

Sergey Sharybin closed this issue

2020-08-11 17:52:28 +02:00

Paul Brunt commented

2020-08-11 18:01:14 +02:00

Thanks all :-)

Thomas Dinges added this to the 2.90 milestone 2023-02-08 16:25:41 +01:00

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Compositor: 'invert' option of the 'Stabilize 2D' node does not work correctly #79563