Add and edit bitmap masks in Pixelmator Pro on Mac
Bitmap masks are pixel-based layer masks used to control the visibility of different areas in a layer. When created, the mask is fully white, and the entire layer is visible in the canvas. Painting on the mask in the canvas with black hides parts of the image. Painting with gray shades provides partial transparency, and painting with white reveals hidden areas again.
Add a bitmap mask to a layer
In Pixelmator Pro on Mac, select a Layer in the Layers sidebar.
Click
at the top of the Layers sidebar, then choose Add Mask.
A white mask thumbnail is added to the Layers sidebar. The white indicates that no areas of the layer are hidden yet. To begin hiding areas in the layer, manually edit the mask.
Mask the background of a layer
Pixelmator Pro can detect background areas in a layer and hide them with a bitmap mask.
In Pixelmator Pro on Mac, select a layer in the Layers sidebar.
Click
The background is masked, rendering it transparent. To manually modify the areas of transparency, edit the mask.
Mask the subject in an image
In Pixelmator Pro on Mac, select a layer in the Layers sidebar.
Add a bitmap mask to the layer.
Control-click the mask layer, then choose Refine Mask.
In the Refine Mask pane, click Mask Subject.
The background of the image is covered in semi-transparent yellow to show which areas of the image will be masked out. You can refine the mask using the controls in the Refine Mask pane or brushes.
Click Apply at the bottom of the pane.
A mask is created around the subject.
Edit a bitmap mask
In Pixelmator Pro on Mac, add a bitmap mask to a layer.
Use the mask controls in the toolbar at the bottom to do any of the following:
Mask (hide) areas of the layer: Click
, then drag in the canvas.
Restore masked (hidden) areas of the layer: Click
, then drag in the canvas over a transparent area.
Adjust the size, softness, or opacity of the Paint or Erase tool: Click
, then drag any of the sliders.
Adjust the opacity, density, or feathering of the mask: Click
, then drag any of the sliders.
Invert the mask: Click Invert Mask. Opaque areas of the layer become transparent, and vice versa.
Edit a mask using the Paint tool
In addition to using the mask controls at the bottom of the canvas, you can use the Paint tool in Tools sidebar to add or remove areas of transparency to a masked layer.
When you add a bitmap mask to a layer, the mask thumbnail in the Layers sidebar is completely white, indicating that no areas of the layer are hidden yet. Painting over the mask layer (in the canvas) with pure black creates areas of transparency (shown as black brush strokes in the layer thumbnail); painting with pure white creates areas of opacity (shown as white brush strokes in the layer thumbnail); and, painting with shades of gray creates varying levels of transparency (shown as gray brush strokes in the layer thumbnail).
In Pixelmator Pro on Mac, select a mask layer in the Layers sidebar.
Select
in the Tools sidebar.
Do any of the following:
Mask (hide) part of an image: Click the color well in the Paint pane, select black, then drag in the canvas.
Reveal part of a masked image: Click the color well in the Paint pane, select white, then drag in the canvas.
Make parts of an image semitransparent: Click the color well in the Paint pane, select a gray shade, then drag in the canvas.
Tip: When you edit a mask with the Paint tool, you can press D to reset the primary and secondary colors in Pixelmator Pro to black and white. Press X to switch between them when painting.
Modify a bitmap mask using Refine Mask controls
After making basic adjustments to a mask, you can further refine it using the Refine Mask controls.
In Pixelmator Pro on Mac, Control-click a mask layer in the Layers sidebar, then choose Refine Mask.
In the Refine Mask pane, use any of the following controls:
Roundness: Drag the slider to make the mask outline rounder.
Softness: Drag the slider to the right to make the mask’s edges softer. Softer edges blend more effectively with other layers.
Expand: Drag the slider right to expand the mask proportionally. Drag left to shrink it.
Mask Subject: Click to automatically apply a mask over the subject in an image.
Smart Refine: Click to use an edge-aware algorithm to intelligently detect details like hair or fur at the edges of the mask and automatically refine the outline.
Invert Mask: Click to make the opaque areas of the mask transparent, and vice versa.
Refine a bitmap mask using brushes
After making basic adjustments to a mask, you can further refine it using various types of brushes.
In Pixelmator Pro on Mac, Control-click a mask layer in the Layers sidebar, then choose Refine Mask.
In the Refine Mask pane, click the brush pop-up menu, then choose a brush type:
Basic Brush: Applies or removes the mask with a normal brush.
Refine Edge Brush: Intelligently detects fine detail near edges when you apply or remove the mask.
Quick Selection Brush: Intelligently analyzes the layer to quickly mask the subject or prominent objects.
Drag any of the following sliders:
Brush Size: Drag to the right to make the brush larger.
Brush Softness: Drag to the right to make the brush softer.
Do either of the following:
Add transparent areas to the mask: Click
, then drag over the image in the canvas.
Add opaque areas to a mask: Click
, then drag over the image in the canvas.
Replace a bitmap mask
You can change the content of a bitmap layer mask to any other image on your Mac.
In Pixelmator Pro on Mac, Control-click a mask layer, then choose Replace Image Mask.
Navigate to an image file on your Mac or a connected device.
Click Replace Mask.
Pixelmator Pro adds a grayscale mask based on the contents of the image.
Automatically mask an image shot in Portrait Mode
When you open an image that was shot in Portrait Mode on iPhone or iPad, Pixelmator Pro automatically masks the background.
In Pixelmator Pro on Mac, open a photo taken with Portrait Mode.
When you open a portrait, a mask layer is included to isolate the subject. To turn on the mask, click the visibility checkbox for the mask layer.
Important: If you drag a photo from the Photos app to Pixelmator Pro, the mask is not imported.