Masking & Qualifiers¶
The MASK tab of the Colour Panel lets you target a colour correction at a specific range of colours in the frame, instead of applying it uniformly. Selecting a qualifier mode, picking a target colour or range, and refining the selection produces a mask that the current layer's grade is applied through.
Qualifier modes¶
| Mode | What it targets |
|---|---|
| HSL | Hue / Saturation / Luminance range gates — enable one or more of the three axes and set a range for each. Starts with no gate enabled (a blank selection) until you engage one. |
| RGB | A colour picked directly, selected by distance in RGB space (Tolerance controls how close a pixel's colour needs to be; Softness controls the falloff at the edge of the selection). Starts unengaged until you pick a colour, drag a slider, or otherwise interact with it. |
| Skin | A preset tuned for skin tones — a deliberate starting selection, not blank. |
| Luminance | A brightness-range gate — defaults to the midtones (0.3–0.7) with its own enable toggle always on. |
A "start here" banner points you toward the eyedropper picker on a freshly-added layer's HSL or RGB qualifier, since both start blank until you engage them.
Picking a selection¶
A grouped toolbar section holds three eyedropper tools:
- PICK — sample a new selection from the clip.
- ADD — expand the current selection by sampling an additional colour.
- SUB — shrink the current selection by sampling a colour to exclude.
These three sit together as one visual group. KEEP (restrict the selection to a drawn region) is a disabled placeholder reserved for a future version.
Refining the matte¶
A horizontal control strip applies to whichever qualifier mode is active — the same five controls work identically across HSL, RGB, Skin, and Luminance:
| Control | What it does |
|---|---|
| Despeckle | Removes small, isolated noise from the selection. |
| Hole Fill | Fills small gaps inside the selection. |
| Feather | Softens the selection's edge. |
| Expand | Grows or shrinks the selection boundary. |
| Intensity | Overall strength of the selection's effect. |
Other controls in the MASK tab:
- Combine mode — Multiply / Min / Max / Subtract, controlling how multiple qualifier gates combine.
- Invert — inverts the current selection.
- HIGHLIGHT — shows/hides the qualifier tint overlay in the Viewer. Turning it off lets you see the plain graded image while a qualifier is defined, without losing the definition itself.
- Overlay tint colour — the colour used to preview the selection in the Viewer.
Geometric shapes¶
A separate SHAPES tab, alongside the qualifier modes above, for masking with drawn shapes instead of a colour range. Shapes layer on top of whichever qualifier mode is active on the layer — an additional, always-on mask source, not a replacement for HSL/RGB/Skin/ Luminance.
Shape types: Rectangle, Ellipse, Bezier Polygon, Bezier Line.
Drawing a shape. Click a shape-type button, then draw it on the Viewer:
- Rectangle / Ellipse — drag out the shape directly.
- Bezier Polygon / Bezier Line — click to place each point (click and hold, then drag, to curve a point before releasing it). A polygon closes when you click its first point again or press Enter; a line finishes with Enter or a double-click and never closes.
Editing points. On an existing bezier shape, select a point to reveal its curve handles, then drag one to bend both sides of the curve together (hold Alt to edit just that one side; Alt-drag the point itself for a quick symmetric curve). Double-click a segment to add a point; select a point and press Delete to remove it.
Shape list. Each shape is a row with its type icon, a name (double-click to rename), an ADD/SUBTRACT toggle, an enable/disable eye button, and a delete button. Drag rows to reorder — order matters for SUBTRACT, which punches a hole out of whatever the shapes above it in the list have already built; ADD unions the shape into the selection.
Selected-shape controls, applying to whichever row is selected:
| Control | What it does |
|---|---|
| Opacity | This shape's own contribution strength before folding with the others. |
| Soft Edge | Feather width, as a percentage of the frame's shorter side. |
| Border | Ring thickness (in RING mode) or ribbon width (Bezier Line), as a percentage of the frame's shorter side. |
| FILL / RING | FILL selects the shape's whole interior. RING selects only a band along its outline. Bezier Line is always a ribbon, so this toggle doesn't apply to it. |
Convert to path. An ellipse can be converted to an editable bezier path (TO PATH button, or the matching on-canvas handle) to get the same point-selection and curve-editing tools as Bezier Polygon. This is one-way — once converted, it's a path, not a true ellipse, anymore.
Viewing the mask¶
The Viewer's Active Mask mode shows the current layer's qualifier selection directly — either as a tinted overlay on the graded image or as a matte (View Mask), depending on the MASK tab's View Mask control. Switching to the MASK tab automatically switches the Viewer to Active Mask, and switching the Viewer to Active Mask by any means switches the Colour Panel to its MASK tab — the two stay in sync in both directions.
Segment¶
A Segment layer is a different layer type, added from the Layer Stack with + Segment Layer. It does not use the qualifier or SHAPES tools on this page — the Colour Panel shows a SEGMENT tab instead.
Type a short subject in plain language ("person", "red jacket", "the dog") and click Segment. Transduce tracks that subject across every frame of the clip in one pass, not frame by frame. + add subject adds another prompt to the same pass. Each subject row has an ADD / SUB toggle: ADD unions the subject into the layer mask; SUBTRACT punches a hole out of subjects above it in the list — the same fold as geometric shapes. A second Segment layer is the intended path when a distinct subject needs its own matte refinement.
Per-layer matte refinement (Despeckle, Hole Fill, Feather, Expand, Intensity) runs once on the folded result of all enabled subjects on that layer — the same engine as the Mask tab, not a separate set of knobs per subject. While a pass is running, Segment becomes Cancel; after a successful pass it reads Re-segment.
If the model weights are not installed yet, Download SAM3 (~3.3GB) appears instead of Segment.
Segment layers use Meta's Segment Anything Model 3 (SAM 3) for subject detection and tracking. Transduce is not affiliated with, endorsed by, or a partner of Meta.
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Colour Panel SEGMENT tab with one subject prompt, ADD/SUB on the chip, the matte-finesse strip, and the Segment action.
Mask Lock¶
The M button on a Layer Stack row freezes a colour-correction layer's current qualifier and shape mask into a per-frame cache, then locks those mask controls so playback and export read the bake instead of recomputing live.
- No mask yet — M opens the MASK tab so you can build one.
- Mask present, unlocked — M bakes every frame and locks the layer. Tooltip: "Bake Mask — freeze this layer's current qualifier."
- Locked — M unlocks. Tooltip: "Bake Mask locked — click to unlock (cache kept)." Unlocking does not throw the cache away, so you can make one change and re-lock.
- Segment layer — M opens the SEGMENT tab. It does not bake. The Segment pass already stores a per-frame matte.
A locked layer with no cached frame for the playhead (for example a frame added after the bake) is bake-stale until you unlock and bake again. Qualifier, shape, and eyedropper edits are ignored while the layer is locked.
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Layer Stack row with the M button showing the lock overlay on a baked qualifier layer.