Mask Editing & Transform

Category: MaskEditControl/Transform · MaskEditControl/Draw · MaskEditControl/Spline · MaskEditControl/Composite · MaskEditControl/Math · MaskEditControl/Batch
VRAM Tier: 1 (pure tensor math — no models loaded)

Eight nodes for precise mask manipulation: per-axis transform, shape drawing (raw + unified), spline mask editor, compositing, math operations, batch management, and visualization.

Nodes

1. Mask Transform XY (MEC)

Independent per-axis mask manipulation. Erode or expand along X and Y separately — unlike most ComfyUI nodes that only offer isotropic (uniform) morph.

File: nodes/mask_transform_xy.py
Category: MaskEditControl/Transform

Parameters

Parameter	Type	Default	Range	Description
`mask`	MASK	—	—	Input mask
`expand_x`	INT	`0`	−512 – 512	Horizontal expand (positive) or erode (negative) in pixels
`expand_y`	INT	`0`	−512 – 512	Vertical expand (positive) or erode (negative) in pixels
`blur_x`	FLOAT	`0.0`	0.0 – 128.0	Gaussian blur sigma along X axis only
`blur_y`	FLOAT	`0.0`	0.0 – 128.0	Gaussian blur sigma along Y axis only
`offset_x`	INT	`0`	−4096 – 4096	Shift mask horizontally in pixels
`offset_y`	INT	`0`	−4096 – 4096	Shift mask vertically in pixels
`feather`	FLOAT	`0.0`	0.0 – 128.0	Isotropic edge feathering (applied after all other transforms)
`threshold`	FLOAT	`0.5`	0.0 – 1.0	Binarize the mask. Set to 0 to keep soft values
`invert`	BOOLEAN	`false`	—	Invert the final mask

Output

Output	Type	Description
`mask`	MASK	Transformed mask

Use Cases

Erode X only: Thin out a mask horizontally while keeping vertical coverage (e.g., narrowing a selection along a wall edge)
Directional blur: Blur only on one axis for motion-like feathering
Offset + threshold: Create crisp shadow/drop masks offset from the original

2. Mask Draw Frame (MEC)

Draw 12 geometric shapes onto a mask with sub-pixel SDF rendering, feathering, rotation, and blend operations.

File: nodes/mask_draw_frame.py
Category: MaskEditControl/Draw

Parameters

Parameter	Type	Default	Range	Description
`width`	INT	`512`	1 – 16384	Canvas width
`height`	INT	`512`	1 – 16384	Canvas height
`shape`	CHOICE	`circle`	See shapes table	Which shape to draw
`shape_params_json`	STRING	`{"cx":256,"cy":256,"radius":50}`	—	JSON with shape-specific parameters (see below)
`value`	FLOAT	`1.0`	0.0 – 1.0	Fill intensity for the shape
`feather`	FLOAT	`0.0`	0.0 – 128.0	Soft edge feathering
`rotation`	FLOAT	`0.0`	−360 – 360	Rotation angle in degrees around the shape center
`operation`	CHOICE	`set`	`set` · `add` · `subtract` · `max` · `min`	How to blend the shape with the existing mask
`existing_mask`	MASK	(optional)	—	Existing mask to draw onto (instead of blank canvas)
`reference_image`	IMAGE	(optional)	—	Reference image for sizing

Shapes and Their JSON Parameters

Shape	JSON Parameters	Example
`circle`	`cx`, `cy`, `radius`	`{"cx": 256, "cy": 256, "radius": 100}`
`rectangle`	`x`, `y`, `w`, `h`	`{"x": 50, "y": 50, "w": 200, "h": 150}`
`ellipse`	`cx`, `cy`, `rx`, `ry`	`{"cx": 256, "cy": 256, "rx": 120, "ry": 80}`
`polygon`	`points`: array of [x,y]	`{"points": [[100,100], [200,50], [300,100]]}`
`line`	`x1`, `y1`, `x2`, `y2`, `thickness`	`{"x1": 10, "y1": 10, "x2": 500, "y2": 500, "thickness": 5}`
`triangle`	`cx`, `cy`, `size` — or `points`	`{"cx": 256, "cy": 256, "size": 100}`
`star`	`cx`, `cy`, `outer_r`, `inner_r`, `num_points`	`{"cx": 256, "cy": 256, "outer_r": 100, "inner_r": 40, "num_points": 5}`
`diamond`	`cx`, `cy`, `w`, `h`	`{"cx": 256, "cy": 256, "w": 120, "h": 180}`
`cross`	`cx`, `cy`, `size`, `thickness`	`{"cx": 256, "cy": 256, "size": 100, "thickness": 30}`
`rounded_rectangle`	`x`, `y`, `w`, `h`, `corner_radius`	`{"x": 50, "y": 50, "w": 200, "h": 150, "corner_radius": 20}`
`heart`	`cx`, `cy`, `size`	`{"cx": 256, "cy": 256, "size": 100}`
`arrow`	`cx`, `cy`, `length`, `width`, `head_length`, `head_width`	`{"cx": 256, "cy": 256, "length": 200, "width": 30, "head_length": 60, "head_width": 80}`

Output

Output	Type	Description
`mask`	MASK	The drawn mask

Tips

Multiple shapes: Chain multiple Mask Draw Frame nodes, each feeding its output as the next node's existing_mask
Rotation: All 12 shapes support rotation around their center point
SDF rendering: Shapes use signed distance field math for smooth, anti-aliased edges
Feathering: Works beautifully with SDF — gives a natural gradient at shape edges

3. Mask Composite Advanced (MEC)

Combine two masks using Boolean, blend, or mathematical operations. Automatically resizes masks if dimensions differ.

File: nodes/mask_composite.py
Category: MaskEditControl/Composite

Parameters

Parameter	Type	Default	Range	Description
`mask_a`	MASK	—	—	First mask
`mask_b`	MASK	—	—	Second mask
`operation`	CHOICE	`union`	See operations table	Compositing operation
`blend_factor`	FLOAT	`0.5`	0.0 – 1.0	Blend ratio (only for `blend` mode). 0 = all A, 1 = all B
`invert_a`	BOOLEAN	`false`	—	Invert mask A before operation
`invert_b`	BOOLEAN	`false`	—	Invert mask B before operation
`threshold`	FLOAT	`0.0`	0.0 – 1.0	Binarize the result. 0 = keep soft values

Operations

Operation	Formula	Description
`union`	`max(A, B)`	Combine both masks
`intersect`	`min(A, B)`	Only where both masks overlap
`subtract`	`clamp(A − B)`	Remove B from A
`xor`	`A + B − 2·min(A,B)`	Either one but not both
`blend`	`A·(1−f) + B·f`	Weighted average using `blend_factor`
`min`	`min(A, B)`	Per-pixel minimum (same as intersect)
`max`	`max(A, B)`	Per-pixel maximum (same as union)
`difference`	`	A − B

Output

Output	Type	Description
`mask`	MASK	Composited mask

4. Mask Math (MEC)

Apply mathematical transformations to a single mask. All outputs are clamped to [0, 1].

File: nodes/mask_math.py
Category: MaskEditControl/Math

Parameters

Parameter	Type	Default	Range	Description
`mask`	MASK	—	—	Input mask
`operation`	CHOICE	`invert`	See operations table	Mathematical operation
`value_a`	FLOAT	`0.0`	−100 – 100	Primary parameter (interpretation depends on operation)
`value_b`	FLOAT	`1.0`	−100 – 100	Secondary parameter

Operations

Operation	`value_a` meaning	`value_b` meaning	Formula
`add_scalar`	Value to add	(unused)	`mask + a`
`multiply_scalar`	Multiplier	(unused)	`mask × a`
`power`	Exponent	(unused)	`mask ^ a`
`invert`	(unused)	(unused)	`1 − mask`
`clamp`	Lower bound	Upper bound	`clamp(mask, a, b)`
`remap_range`	Source min	Source max	Map `[a, b]` → `[0, 1]`
`quantize`	Number of levels	(unused)	Snap to N discrete steps
`threshold_hysteresis`	Low threshold	High threshold	Dual-threshold with connected components
`gamma`	Gamma value	(unused)	`mask ^ (1/a)`
`contrast`	Contrast strength	Midpoint (default 0.5)	S-curve contrast adjustment
`abs_diff_from_value`	Reference value	(unused)	`

Output

Output	Type	Description
`mask`	MASK	Transformed mask, clamped to [0, 1]

5. Mask Batch Manager (MEC)

Manipulate mask batches for video workflows: slice, pick specific frames, repeat, reverse, concatenate, and more.

File: nodes/mask_batch_manager.py
Category: MaskEditControl/Batch

Parameters

Parameter	Type	Default	Range	Description
`mask`	MASK	—	—	Input mask batch
`operation`	CHOICE	`slice`	See operations table	Batch operation
`param_a`	INT	`0`	0 – 99999	Start frame (slice), frame index (pick/set/insert/remove), or repeat count
`param_b`	INT	`-1`	−1 – 99999	End frame for slice (−1 = end). Ignored for other ops
`frame_indices`	STRING	`""`	—	Comma-separated frame indices for `pick_frames` mode
`mask_b`	MASK	(optional)	—	Second mask batch for `concat`, `interleave`, `set_frame`

Operations

Operation	`param_a`	`param_b`	Description
`slice`	Start frame	End frame (−1 = end)	Extract frame range `[a:b]`
`pick_frames`	(unused)	(unused)	Select specific frames from `frame_indices` string
`repeat`	Repeat count	(unused)	Repeat the mask batch N times
`reverse`	(unused)	(unused)	Reverse frame order
`concat`	(unused)	(unused)	Join mask + mask_b along batch dimension
`interleave`	(unused)	(unused)	Alternate frames: mask[0], mask_b[0], mask[1], mask_b[1], …
`set_frame`	Frame index	(unused)	Replace frame at index with mask_b
`insert_frame`	Insert position	(unused)	Insert mask_b at position
`remove_frame`	Frame index	(unused)	Remove frame at index

Outputs

Output	Type	Description
`mask`	MASK	Modified mask batch
`count`	INT	Number of frames in the output batch

6. Mask Preview Overlay (MEC)

Visualize masks overlaid on images with 5 display modes, customizable colors, edge highlighting, and bounding box display.

File: nodes/mask_preview.py
Category: MaskEditControl/Preview
Output Node: Yes (can be used as a terminal node)

Parameters

Parameter	Type	Default	Range	Description
`image`	IMAGE	—	—	Background image
`mask`	MASK	—	—	Mask to visualize
`display_mode`	CHOICE	`overlay`	See modes table	Visualization mode
`overlay_color_r`	FLOAT	`1.0`	0.0 – 1.0	Red component of overlay color
`overlay_color_g`	FLOAT	`0.0`	0.0 – 1.0	Green component
`overlay_color_b`	FLOAT	`0.0`	0.0 – 1.0	Blue component
`opacity`	FLOAT	`0.4`	0.0 – 1.0	Overlay opacity
`edge_width`	INT	`2`	0 – 20	Edge contour width in pixels
`show_bbox`	BOOLEAN	`false`	—	Draw bounding box of the mask region
`bbox_color_r/g/b`	FLOAT	`0/1/0`	0.0 – 1.0	Bounding box color (default: green)
`bbox`	BBOX	(optional)	—	External bbox to draw (overrides auto-detect)

Display Modes

Mode	Description
`overlay`	Semi-transparent colored tint over masked region
`mask_only`	Black and white mask only (no image)
`side_by_side`	Original image next to the overlay version
`checkerboard`	Transparent area shown as checkerboard pattern
`edge_highlight`	Only the mask boundary contour drawn on the image

Output

Output	Type	Description
`preview`	IMAGE	The visualization image

Handles batch size mismatches automatically (repeats the shorter batch to match the longer one).

7. Draw Shape (MEC)

Unified 12-shape drawing node with a single dropdown. All parameters are exposed as named inputs (no JSON editing). Irrelevant parameters are ignored per shape. Replaces the 5 legacy per-shape wrapper nodes.

File: nodes/mask_draw_frame.py
Category: MaskEditControl/Draw

Parameters

Parameter	Type	Default	Range	Description
`width`	INT	`512`	1 – 16384	Canvas width
`height`	INT	`512`	1 – 16384	Canvas height
`shape`	CHOICE	`circle`	12 shapes	Shape to draw
`cx` / `cy`	FLOAT	`256.0`	−16384 – 16384	Center position (center-based shapes)
`radius`	FLOAT	`50.0`	0 – 8192	Circle radius; triangle/heart size
`size_w` / `size_h`	FLOAT	`200` / `100`	0 – 16384	Rectangle, rounded_rect, diamond, arrow
`rx` / `ry`	FLOAT	`100` / `50`	0 – 8192	Ellipse X/Y radii
`top_left_x` / `top_left_y`	FLOAT	`100`	−16384 – 16384	Top-left or line start
`x2` / `y2`	FLOAT	`400`	−16384 – 16384	Line end position
`thickness`	FLOAT	`5.0`	0 – 500	Line/cross thickness
`outer_r` / `inner_r`	FLOAT	`100` / `40`	0 – 8192	Star outer/inner radii
`num_points`	INT	`5`	3 – 50	Star/polygon point count
`corner_radius`	FLOAT	`20.0`	0 – 4096	Rounded rectangle corners
`cross_size`	FLOAT	`100.0`	0 – 8192	Cross arm length
`arrow_length` / `head_length` / `head_width`	FLOAT	—	0 – 16384	Arrow dimensions
`points_json`	STRING	—	multiline	Polygon vertices `[[x1,y1],...]`
`value`	FLOAT	`1.0`	0.0 – 1.0	Fill intensity
`feather`	FLOAT	`0.0`	0.0 – 128.0	Edge feathering
`rotation`	FLOAT	`0.0`	−360 – 360	Rotation degrees
`operation`	CHOICE	`set`	`set` · `add` · `subtract` · `max` · `min`	Blend with existing mask
`batch_size`	INT	`1`	1 – 256	Number of mask frames

Optional: coords_json, existing_mask, reference_image

Shape → Parameter Reference

Shape	Uses
`circle`	cx, cy, radius
`rectangle`	top_left_x, top_left_y, size_w, size_h
`ellipse`	cx, cy, rx, ry
`polygon`	points_json, num_points
`line`	top_left_x, top_left_y, x2, y2, thickness
`triangle`	cx, cy, radius
`star`	cx, cy, outer_r, inner_r, num_points
`diamond`	cx, cy, size_w, size_h
`cross`	cx, cy, cross_size, thickness
`rounded_rectangle`	top_left_x, top_left_y, size_w, size_h, corner_radius
`heart`	cx, cy, radius
`arrow`	cx, cy, arrow_length, size_w, head_length, head_width

Output

Output	Type	Description
`mask`	MASK	Drawn shape mask

8. Spline Mask Editor (MEC)

Interactive canvas for drawing spline-based masks directly on your image. Three interpolation modes with normalized-coordinate persistence and segment insertion.

File: nodes/spline_mask_editor.py + js/spline_mask_editor.js
Category: MaskEditControl/Spline

Parameters

Parameter	Type	Default	Range	Description
`image`	IMAGE	—	—	Reference image shown in editor canvas
`spline_data`	STRING	`"[]"`	multiline	Internal serialized state (do not edit manually)
`spline_type`	CHOICE	`catmull_rom`	`catmull_rom` · `bezier` · `polyline`	Interpolation method
`closed`	BOOLEAN	`true`	—	Close the spline loop (filled region)
`smoothing`	BOOLEAN	`true`	—	Enable spline smoothing
`samples_per_segment`	INT	`20`	2 – 100	Curve resolution per segment
`feather_radius`	FLOAT	`0.0`	0.0 – 64.0	Gaussian blur on mask edge
`invert`	BOOLEAN	`false`	—	Fill outside spline instead of inside

Optional: width / height (INT, override dimensions; 0 = match image)

Editor Controls

Action	Effect
Left click	Add point (or close path by clicking first point)
Shift + click	Delete point under cursor
Ctrl + click	Insert point on nearest curve segment
Right-click	Context menu (Delete, Open/Close, Smooth/Sharp)
S key	Toggle smooth / sharp
Scroll	Zoom
Middle drag	Pan

Outputs

Output	Type	Description
`mask`	MASK	Rasterized filled spline region (B, H, W)
`coords_json`	STRING	SAM-compatible point coords from control points
`spline_data_out`	SPLINE_DATA	Structured data for downstream nodes

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Mask Editing & Transform

Nodes

1. Mask Transform XY (MEC)

Parameters

Output

Use Cases

2. Mask Draw Frame (MEC)

Parameters

Shapes and Their JSON Parameters

Output

Tips

3. Mask Composite Advanced (MEC)

Parameters

Operations

Output

4. Mask Math (MEC)

Parameters

Operations

Output

5. Mask Batch Manager (MEC)

Parameters

Operations

Outputs

6. Mask Preview Overlay (MEC)

Parameters

Display Modes

Output

7. Draw Shape (MEC)

Parameters

Shape → Parameter Reference

Output

8. Spline Mask Editor (MEC)

Parameters

Editor Controls

Outputs

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Mask Editing & Transform

Nodes

1. Mask Transform XY (MEC)

Parameters

Output

Use Cases

2. Mask Draw Frame (MEC)

Parameters

Shapes and Their JSON Parameters

Output

Tips

3. Mask Composite Advanced (MEC)

Parameters

Operations

Output

4. Mask Math (MEC)

Parameters

Operations

Output

5. Mask Batch Manager (MEC)

Parameters

Operations

Outputs

6. Mask Preview Overlay (MEC)

Parameters

Display Modes

Output

7. Draw Shape (MEC)

Parameters

Shape → Parameter Reference

Output

8. Spline Mask Editor (MEC)

Parameters

Editor Controls

Outputs