Introduction

The Image Editor is made of several areas. At the right side you will find the sidebar. Here you will find further options and settings for the Image Editor and its tools.

The tools tab in paint mode contains several panels with functionality for the brushes. The Image tab contains image related settings. And so on.

The Scopes tab just appears with an image selected.

Right Click menus

You will open the usual right click menus when clicking with the right mouse at elements in the sidebar. Its content is in big parts self explaining.

The right click menus are explained in the chapter 6 Editors Introduction.

Tool Tab in Paint Mode

Tool Tab

In View and Mask mode you don't have any further content in the Tool tab. But in Paint mode the tools tab contains several panels with functionality for the brushes. It is in big parts similar functionality to the paint tools in the 3D view.

The Brush panel shows different content, dependent of which brush is chosen in the tool shelf.

Save Image

A short warning. A modified image does NOT save with the scene. You have to save out the image when you want to save the changes at the texture. There is no warning. So DON'T FORGET TO SAVE THE IMAGE.

Brush Asset Panel

The Brush Asset Panel contains the different Brushes and some Brush settings. Choose and adjust your current active brush.

Browse Brush

The big image at the top is a dropdown box that allows you to choose a brush. Click at it, and you will see the different brushes. A click at one of the images will choose this brush then.

Brushes are assets. You can load them from different libraries if you want.

Brush Specials menu

This menu becomes active when you create a new brush. Which can be done wiht the Plus button in the name property. This data cannot be changed for builtin system brushes.

Edit Metadata

Calls a popup where you can adjust further informations and settings for the brush.

Brush settings Panel

The Brush Panel contains the different paint brushes, a color dialog, and some brush settings.

Blend

Define how the stroke will blend. You can choose between various blend modes.

Size

The Radius edit box allows you to adjust the radius of the brush. The button behind the edit box enables tablet pressure sensitivity for radius.

Size Pressure

The first button behind the edit box enables tablet pressure sensitivity for radius.

Pressure Size Curve

Behind the pressure size button there is a button to reveal the size pressure curve panel. When you activate Size Pressure for tablets, then the Size Pressure curve becomes active, and can be adjusted.

The pressure size curve allows you to adjust the falloff curve for the tablet pressure. It shows when Use Pressure is activated. The curve panel shows when clicking at the button.

Selecting Points

You can select curve points. This reveals two edit boxes for the x and y coordinate of this point.

Selected points can be moved around. Left click at them, hold the mouse button down and move them to a new location.

Adding Points

You can add new curve points by simply left clicking at the curve. Move the mouse to position them where you need it.

Navigation elements

Clipping options

Set up clipping for the stroke.

Tools

Tools is a menu where you can find some curve related tools.

Handles

You can choose between Auto handle, Vector Handle and Auto Clamped.

Position X / Y

The position of the selectedc curve point.

Delete Points

Deletes the selected curve point.

Curve Presets

A curve preset to start with.

Use Unified Radius

The second button behind the edit box enables global radius size. Any modification at the radius will also modify the radius value for other paint tools.

Strength

The Strength edit box allows you to adjust the strength of the brush. The button behind the edit box enables tablet pressure sensitivity for strength.

Size Pressure

The first button behind the edit box enables tablet pressure sensitivity for radius.

Pressure Size Curve

Behind the pressure size button there is a button to reveal the size pressure curve panel. When you activate Size Pressure for tablets, then the Size Pressure curve becomes active, and can be adjusted.

The pressure size curve allows you to adjust the falloff curve for the tablet pressure. It shows when Use Pressure is activated. The curve panel shows when clicking at the button.

Selecting Points

You can select curve points. This reveals two edit boxes for the x and y coordinate of this point.

Selected points can be moved around. Left click at them, hold the mouse button down and move them to a new location.

Adding Points

You can add new curve points by simply left clicking at the curve. Move the mouse to position them where you need it.

Navigation elements

Clipping options

Set up clipping for the stroke.

Tools

Tools is a menu where you can find some curve related tools.

Handles

You can choose between Auto handle, Vector Handle and Auto Clamped.

Position X / Y

The position of the selectedc curve point.

Delete Points

Deletes the selected curve point.

Curve Presets

A curve preset to start with.

Use Unified Radius

The second button behind the edit box enables global radius size. Any modification at the radius will also modify the radius value for other paint tools.

Brush Settings Panel - Color Picker Sub panel

Define the color for your brush.

The active color is the left one. When you click the button with the two arrows down right then you can swap the color with the secondary color. Then this secondary color becomes the primary color, and is active.

A click at one of the color fields will open a more detailed color dialog, to set up the color by using rgb, hsv and hex colors and with value sliders.

Brush Settings Panel - Color Palette Sub panel

Create a color palette for later reuse.

First create a new palette by clicking at New. Then adjust the color in the color picker. And then click at the add button to add this color to the palette.

To set the color picker to a palette color simply click at this palette color.

To remove a color from the palette, choose it, then click at the remove button. The active palette color that gets removed is the one with the triangle at it.

The color palette cannot be saved externally. It is part of the current blend file. You can however append color palettes from other blend files.

The elements are explained from left to right.

Palette browser

The button at the left opens a drop down list where you can choose between your palettes.

Brush Settings Panel - Advanced Sub panel

This sub panel contains brush specific settings.

Brush type Draw

Brush type Soften

Brush type Smear

Anti Aliasing

Smooths the edges of the strokes.

Brush type Clone

Brush type Fill

Anti Aliasing

Smooths the edges of the strokes.

Brush type Mask

Randomize Color subtab

Jitter the brush color.

Brush Settings Panel - Texture Sub panel

Texture Panel

The Texture panel allows you to paint with textures. This allows you for example to grab a photo from some fish scales, and simply paint them onto the mesh by using this image as a pencil. Or as a blueprint where you calk through ( Stencil method ).

Browse Texture to be linked

The image at the top of the panel is an image browser. Choose a texture that you can choose for painting then. You can also have more than one image loaded at once.

In this shot there is already a texture added. The way to add the texture here is a bit more complicated. And not done with clicking at the New button.

First click at the New button below the image. This will create a new texture slot. This slot is still empty, it displays black.

We need to load a texture in this slot. This must be done in the Properties editor in the Textures tab.

The problem is, we have most probably an object with a material and a texture already selected. And when we change this texture , then we don't get the pencil texture loaded. But we change the texture at our mesh.

What we need to do is to create a material first. And in this material we load our pencil texture then. And then this texture becomes available in the image browser of the Texture panel. Note that you need to be in texture paint mode to see the texture tab in the properties editor. It does not show in object mode.

And when we go back to the texture panel, then the texture should be loaded here. And we can work with this texture.

Brush Mapping with mapping method Tiled

The brush mapping method Tiled tiles the brush stroke at the surface. The mapping happens from the current view. The result may be distorted when the view does not align with the surface of the object.

Angle

The angle of the brush.

Brush Mapping with mapping method View Plane

The brush mapping method View Plane simply paints onto the surface. The mapping happens from the current view. The result may be distorted when the view does not align with the surface of the object.

Angle

The angle of the brush.

Rake

The angle follows the direction of the brush stroke.

Random

The brush angle gets set random.

Random Angle

Brush texture random angle.

Brush Mapping with mapping method 3D

The brush mapping method 3D paints the texture at the surface, by tiling it 1/1 at the object surface.

Offset

The offset of the texture in the brush.

Size

The size of the texture in the brush.

Brush Mapping with mapping method Random

The brush mapping method Random paints onto the surface, and randomizes the texture position in the brush while that. The mapping happens from the current view. The result may be distorted when the view does not align with the surface of the object.

Angle

The angle of the brush.

Brush Mapping with mapping method Stencil

The former methods uses the textures for the brush. The method Stencil works different. You have your texture displayed in the workspace above the object, and you paint this texture onto your object with your pencil strokes.

Note that the texture in the 3d space is just visible when you are with the mouse over the viewport.

The stencil map gets by default displayed down left in the 3d view. You have to position it where you need it.

Hotkeys ctrl right mouse, shift right mouse and alt right mouse.

Brush Settings Panel - Texture Mask Sub panel

Texture Mask Panel

The texture mask panel allows you to use a texture as a mask to define the strength of painting. It paints just where the mask texture is bright. You can also use gradients to define the paint strength.

Browse Texture to be linked

The image at the top of the panel is an image browser. Choose a texture that you can choose for painting then. You can also have more than one image loaded at once.

In this shot there is already two textures added. The way to add the texture here is a bit more complicated. And not done with clicking at the New button.

First click at the New button below the image. This will create a new texture slot. This slot is still empty, it displays black.

We need to load a texture in this slot. This must be done in the Properties editor in the Textures tab.

The problem is, we have an object with a material and a texture already selected. And when we change this texture , then we don't get the pencil texture loaded. But we change the texture at our mesh.

What we need to do is to create a material first. And in this material we load our pencil texture then. And then we can choose this texture in the image browser of the texture.

And when we switch back to the tools tab, then the texture is loaded. And we can work with this texture.

Make sure that you use another texture in the Texture panel than in the Texture Mask panel, or no texture at all. When both is the same then you will get the same result with all Mask Mapping methods since they overlap each other at the very same positions.

Brush Mapping with mapping method View Plane

The brush mapping method View Plane simply paints onto the surface. The mapping happens from the current view. The result may be distorted when the view does not align with the surface of the object.

Pressure Masking

Enable pressure masking when you use a tablet.

Angle

The angle of the brush.

Rake

The angle follows the direction of the brush stroke.

Random

The brush angle gets set random.

Random Angle

Brush texture random angle.

Brush Mapping with mapping method Tiled

The brush mapping method Tiled tiles the brush stroke at the surface. The mapping happens from the current view. The result may be distorted when the view does not align with the surface of the object.

Pressure Masking

Enable pressure masking when you use a tablet.

Angle

The angle of the brush.

Brush Mapping with mapping method Random

The brush mapping method Random paints onto the surface, and randomizes the texture position in the brush while that.

Pressure Masking

Enable pressure masking when you use a tablet.

Mask Pressure Mode

A drop down box to choose the mask pressure mode for tablets.

Angle

The angle of the brush.

Brush Mapping with mapping method Stencil

The former methods uses the textures for the brush. The method Stencil works different. You have your texture displayed in the workspace above the image, and you paint this texture onto your object with your pencil strokes.

Note that the stencil texture is just visible when you are with the mouse over the viewport. It gets by default displayed down left. You have to position it where you need it. See Brush menu, Stencil Texture controls.

Pressure Masking

Enable pressure masking when you use a tablet.

Angle edit box

Adjust the angle of the brush. The button at the end allows you to set the radius by dragging the mouse. This should be done in the viewport and with the hotkey. This button is just a visible reminder.

Stroke Panel

Stroke Panel

The Stroke panel contains settings to influence the behavior of the brush stroke. There are various stroke methods available. We will go through them one by one.

Stroke method Space

This is the default Stroke method. The stroke gets added continuously with given settings.

Spacing Edit Box

The sculpt drawing happens by mapping the pencil onto the mouse position. And when you move the mouse then the next mapping happens. Adjust the spacing after what mouse movement the next mapping should happen. The lower the value, the lower the distance between the single dots.

Spacing Pressure

The icon behind the edit box enables tablet pressure sensitivity for tablets.

Jitter Edit Box

Add Jitter to the brush while painting.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Curve

The Stroke method curve doesn't simply influence the way how the stroke is painted. It is a special method.

First you draw a curve object by holding down ctrl and clicking with right mouse button. Then you tweak the curve. You can click at the curve point, and drag out handlers to make the curve points smooth. This way you get one handler. When you click and drag then you will get two handlers at the curve point.

When done you hit the Draw Curve button or click left outside of the image. And the curve gets drawn onto the surface.

Spacing Edit Box

The drawing happens by mapping the pencil onto the mouse position. And when you move the mouse then the next mapping happens. Adjust the spacing after what mouse movement the next mapping should happen. The lower the value, the lower the distance between the single dots.

The icon behind the edit box enables tablet pressure sensitivity for tablets.

Paint Curve edit box

Here you set the active curve.

The first element is a drop down box where you will find your curves objects. You can have more than one.

The second element is the edit box that displays the active curve.

The number right of it, in this case 2, indicates how much number of users ( internally ) this brush uses. This means that this data block (the brush) shares currently settings with at least one other object. Most probably the parent brush where we have created it from. Click at the value to make this brush a single user. The button will vanish then.

F set the brush to have a fake user. Zero user data-blocks are normally not saved. But sometimes you want to force the data to be kept even when the data block has no user.

The + button allows you to add a new pencil with the current settings. Note that the brushes are NOT saved when you close Bforartists. You can save them into the current blend file. Or you can save the startup file. But be careful here. This saves everything else of the current state of Bforartists too.

The X button deletes the brush as the active one. It does NOT delete it from the brushes list.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Line

With Stroke method line you draw a line between a starting point and an endpoint. And when you release the mouse then the line gets drawn.

Spacing Edit Box

The drawing happens by mapping the pencil onto the mouse position. And when you move the mouse then the next mapping happens. Adjust the spacing after what mouse movement the next mapping should happen. The lower the value, the lower the distance between the single dots.

The icon behind the edit box enables tablet pressure sensitivity for tablets.

Jitter Edit Box

Add Jitter to the brush while painting.

Input Samples Edit Box

Average multiple input samples together to smooth the brush stroke.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Anchored

Click and drag to place a dot and to scale it.

Edge to edge

Drag Anchor Brush from edge to edge.

Jitter Edit Box

Add Jitter to the brush while painting.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Airbrush

The stroke acts like an airbrush pencil. The dots gets placed randomly.

Input Samples Edit Box

Average multiple input samples together to smooth the brush stroke.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Drag Dot

Paint a dot and drag it around. The actual painting happens then at releasing the mouse.

Jitter Edit Box

Add Jitter to the brush while painting.

Input Samples Edit Box

Average multiple input samples together to smooth the brush stroke.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Stroke method Dots

The stroke method Dots draws dots of the pencil onto the surface. The mapping happens from the current view. Means you will get distortions when your view is not aligned with the surface of the object.

Jitter Edit Box

Add Jitter to the brush while painting.

Input Samples Edit Box

Average multiple input samples together to smooth the brush stroke.

Stabilize Stroke subpanel

The brush lags behind the mouse position, and produces a much smoother stroke by that.

Brush Settings Panel - Falloff Sub panel

The curve panel allows you to define different falloffs methods for the border of the brush.

Selecting Points

You can select curve points. This reveals two edit boxes for the x and y coordinate of this point.

Selected points can be moved around. Left click at them, hold the mouse button down and move them to a new location.

Adding Points

This setting uses the curve widget: click to add points, drag to move them. See Curve Widget in the Interface chapter.

Navigation elements

The navigation elements at the top are described from left to right.

Zoom in and out

The two buttons with the magnifying glass at it zooms in and out in the curve window.

Use Clipping

Clipping options. Set up clipping for the stroke.

Tools

Tools is a menu where you can find some curve related tools.

Curve Presets

Predefined curve presets.

Brush Settings Panel - Brush Tip Sub panel

Adjust the color and appearance of the brush cursor to custom values.

Brush Tip Checkbox

Activate the custom settings.

Cursor Color

Choose another color for the brush cursor. Double clicking at the color field will open a color picker.

Falloff Opacity

You can turn on the cursor overlay with the eye button at the end. The falloff opacity slider allows you to adjust the opacity of this cursor overlay.

Texture Opacity

This is for the case when you paint with a texture brush. You can turn on the Texture overlay with the eye button at the end. The falloff opacity slider allows you to adjust the opacity of this cursor overlay.

Mask Texture Opacity

This is for the case when you mask paint with a texture brush. You can turn on the Texture overlay with the eye button at the end. The falloff opacity slider allows you to adjust the opacity of this cursor overlay.

Tiling panel

Tiling allows you to draw over the borders and continue the stroke at the other side of the image. You can tile in X and Y direction.

Image Tab

Introduction

In the Image tabs you can find further options and image settings. These settings changes, dependent of what you have selected. And in what mode you are.

Image Panel

Find image related settings. Size, type, and so on.

Source

Choose the image type. This type gets usually automatically set. When you create a new image, then this image is generated. When you load an image then the Source switches to Single Image.

Generated images does not have a path.

Source Type Single Image

Path edit box

Color Space

The color space for the image.

Alpha

How to calculate the alpha channel.

Half Float Precision

Just with image material that uses 32 bit float. Use just 16 Bit per channel instead of the full 32 bit. This lowers the memory usage while rendering.

View as Render

Display the image with using the color management settings. The color management can be adjusted in the properties editor in the Render tab.

Seam Margin

This option belongs to the UV Editor, and has no effect in the Image editor. Take a margin into account when fixing UV seams during painting.

Source Type Movie + Image Sequence

Path edit box

Color Space

Choose the color space type for the movie or image sequence files.

Alpha

Choose the alpha channel mode. Straight or Premultiplied.

Half Float Precision

Just with image material that uses 32 bit float. Use just 16 Bit per channel instead of the full 32 bit. This lowers the memory usage while rendering.

View as Render

Display the image with using the color management settings. The color management can be adjusted in the properties editor in the Render tab.

Seam Margin

This option belongs to the UV Editor, and has no effect in the Image editor. Take a margin into account when fixing UV seams during painting.

Source Type Generated

X / Y

The image width and height.

Float Buffer

Use a floating point buffer. 8 Bit images uses integers. 32 Bit works with floats.

Generated Type Blank

This type displays an image with one blank color

Color

The color of the blank image.

Generated Type UV Grid

This type displays a with a black and white checker texture but colored dots.

Generated Type Color Grid

This type displays a with a colored checker texture with numbers.

Color Space

Choose the color space type for the image.

Half Float Precision

Just with image material that uses 32 bit float. Use just 16 Bit per channel instead of the full 32 bit. This lowers the memory usage while rendering.

View as Render

Display the image with using the color management settings. The color management can be adjusted in the properties editor in the Render tab.

Seam Margin

This option belongs to the UV Editor, and has no effect in the Image editor. Take a margin into account when fixing UV seams during painting.

Source Type Udim

UDIM is an enhancement to the UV mapping and texturing workflow. And does not belong here. But in the UV Editor. It is just in the list because it shares the same menus with the UV Editor.

Info string

Some information about the currently loaded image. Resolution and color space.

Color Space

Choose the color space type for the movie or image sequence files.

Alpha

Choose the alpha channel mode. Straight or Premultiplied.

Half Float Precision

Just with color space sRGB. Use just 16 Bit per channel instead of the full 32 bit. This lowers the memory usage while rendering.

View as Render

Display the image with using the color management settings. The color management can be adjusted in the properties editor in the Render tab.

Seam Margin

This option belongs to the UV Editor, and has no effect in the Image editor. Take a margin into account when fixing UV seams during painting.

UDIM Tiles Panel

Manage UDIM tiles. This panel shows with source type UDIM.

UDIM Tile List

List all UDIM tiles associated with the main index (1000 tile). Double clicking on the tile name allows renaming.

Add Tile

Adds new UDIM tiles to the group.

Add Tile dialog

Generated Type

The generated texture type.

32 bit float

Generate an image with 32 bit floating point bit depth.

Remove Tile

Remove the selected UDIM tile. Note that the place in the texture will then be blank. The tiles does not resort. The next created UDIM tile will then be placed in this gap.

Fill Tile

Occupy the UDIM tile with a Generated Image. You can change the fill type and texture tile size of a UDIM tile also afterwards with this fill tool. Note that this overwrites the settings of the currently active UDIM tile.

Fill tile dialog

Generated Type

The generated texture type.

32 bit float

Generate an image with 32 bit floating point bit depth.

UDIM Workflow

First set up the grid shape for the UDIM tiles.

This panel is in the View tab. And will vanish in the moment you add any texture. So do this setup beforehand. There is no way to show and change this grid panel afterwards.

Unwrap your mesh.

Add a generated texture, with generated type Color Grid (optional ), and Tiled ticked.

In the viewport you will now see one square UV space again, with the colored background image. And we have our first UDIM tile in the UDIM Tile list.

In the Tile list click at the Add button. And add another image. This time with another resolution.

The result is that we have two tiles besides each other, with different resolution.

Create a third one. Or as much as you need.

Next move the UV parts to the texture areas where you need them.

Now save the image. And by saving the one UDIM image all the sub images of this UDIM texture gets saved too.

Save the blend file. Modify the textures to your needs.

To reload the modified textures either save, close and open Bforartists and reload the scene. Or use Open Image to open the first image of the UDIM textures. The rest will load automatically.

Next create a material. Add a texture. Choose the UDIM texture. And the material will now render with the UDIM textures applied.

Metadata Panel

Displays existing meta data of the image file.

View Tab

See and set the 2D cursor location.

This panel is just visible in Mask mode.

Introduction

The View tab contains some view related settings. And it contains the annotation panel.

Display Panel

Annotations Panel

Manage the Annotation layers and materials.

When you don't have drawn an annotation yet then the panel just contains a New button.

Annotations prop

Add, remove and rename new annotations.

Drop down box

A list of the available annotation layers.

List of Annotation Strokes

Here you see your Annotation layers for the current Annotation. Every layer can have an own color.

At the right side you find buttons to sort them and to add and remove new Annotation layers.

You can change the color by clicking at the color field. A color dialog will pop up. You can rename annotation layers by double clicking at it.

The eye icon allows you to make it invisible And it has a search field.

Scopes Tab

Scopes Tab

The Scopes tab contains several panels with analytic tools.

Histogram

Histogram is a graph that displays the color distribution of the pixels in the image. The range from left to right goes from 0, which represents black, to 255, which represents white. And the height represents how much pixels in the image have this specific color.

The different display modes are:

Waveform

The waveform graph is another way to display the color information of the image.

Waveform Opacity

Adjust the opacity of the pixels in the waveform histogram.

Waveform Mode

This is a drop down box menu where you can choose further options.

Vectorscope

This is a graph to display the pixel color distribution in the image in a radial way. The radial arrangement allows to display data that is behind the maximum 255 of the normal histogram. This can happen with 32 bit float images for example.

Vectorscope Opacity

Adjust the opacity of the pixels in the waveform histogram.

Vectorscope Mode

How to display the vectoscope.

Sample Line

The Sample Line scope is a graph that allows you to get the sample data from a line.

Click at the Sample Line button above the histogram to draw a line. The pixels under this line will then be used to read the sample data from.

The different display modes are:

Samples

The general sample settings for the above histograms. More accurate or more fast.

Mask Tab

Introduction

The mask tab just shows in Mask mode and with an existing mask.

It contains tools and settings for the mask mode. Like a layer system.

Mask Settings Panel

This values are of interest for the Sequencer, where you work with movies and image sequences.

Mask Layers Panel

When you add a spline, a circle or a square or a freehand one, then a Mask Layer gets created.

You can create several mask layers and work with them in the sequencer or the Node editors. They can be used to create complex shapes, and define how the splines interact with each other. Splines at the same layer can be animated together.

Splines can be copied and pasted from one layer to another.

Mask Layer List

The list of available mask layers.

Restrict View

Don't show this mask layer in the viewport.

Restrict Select

Selection in the viewport is enabled or disabled. The spline handlers becomes invisible.

Restrict Render

Don't render this mask layer for the final image(s).

Drag Handler

The two vertical lines at the end is a handler with which you can expand the list.

Search Field

You can expand a search field at the bottom of the list. Type in your term and hit enter to filter for your term.

Add Mask Layer

Add a new mask layer to the list.

Adjust Last Operation - Add Mask Layer

Name

Rename the new created mask layer.

Note that you can also rename it in the list.

Opacity

Set the opacity of the mask layer.

Invert

Inverts the values (colors) in the mask layer.

Blend

Adjust the layer blending.

Note, Merge add and Merge subtract should be used with a Feather on overlapping masks to get a better result.

Falloff

Adjust the Feather falloff

Overlap

Fill self-intersecting areas.

Holes

Overlapping splines from the same layer will generate holes in the mask.

Mask Layers Panel

When there is a spline in the current mask layer, then the Active Spline Panel shows. Adjust some settings for the currently active spline.

Feather Offset

The method to calculate the feather offset.

Interpolation

The weight interpolation method.

Active Point Panel

When you select a point of one of the splines, then the Active Point Panel will show up.

This panel is of interest for motion tracking. Control Points can be parented to motion tracks. And this allows to mask out parts of the motion tracked footage.

The masking happens at the Viewer Node.