VFX Atlas
M 062 / 18302 Masks & Controlalgorithm output

Convex Hull Mask

masks & control

Typeface · Sarpanch

Atlas demonstration: the free source photo and the computed Convex Hull Mask. A complex botanical specimen is rendered through teal and dark green thresholds against a black void. The resulting yellow outline perfectly demonstrates the algorithm's ability to simplify organic complexity into a single, smooth convex envelope.
Atlas demonstration: the free source photo and the computed Convex Hull Mask. A complex botanical specimen is rendered through teal and dark green thresholds against a black void. The resulting yellow outline perfectly demonstrates the algorithm's ability to simplify organic complexity into a single, smooth convex envelope.Image: NeONBRAND neonbrand · CC0 (via Wikimedia Commons), processed for the AtlasView source ↗

Prompt

Apply a Convex Hull Mask effect to the main subject silhouette, enclosing its outermost points within one solid white convex polygon against black. Bridge inward dents, fill every interior hole, and use straight, angular boundary segments without texture or shading. Keep the original subject and composition.

Paste it into LetzAI with your own image to apply the effect ↗

Identify

A solid angular mask encloses the selected pixels, filling holes and bridging inward dents in their outline.

Principle

The algorithm finds the convex hull1: the smallest convex shape containing all selected pixels, then fills its interior. It uses an existing selection or binary mask2, rather than identifying objects itself.

Try it out

Vary the starting selection and watch how isolated pixels stretch the enclosing shape.

Classification

Calculated image processing result.

Further examples · 9 images

Convex Hull Mask, applied to “Jimmy Bay 2017-02-06 (Unsplash)”
02 Convex Hull Mask, applied to “Jimmy Bay 2017-02-06 (Unsplash)”A silhouette of a person appears centered within a larger rectangular frame. Multiple yellow boundaries are present, showcasing how the algorithm treats disconnected pixel clusters as distinct convex shapes.Jimmy Bay jimmymystic (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Colorful Autumn Flowers (44572387344)”
03 Convex Hull Mask, applied to “Colorful Autumn Flowers (44572387344)”A central splash of texture is surrounded by several floating peripheral shapes. The large central yellow boundary clearly illustrates how the algorithm ignores internal voids to create the tightest possible outer shell.Markus Spiske from Forchheim, Bavaria Upper Franconia (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Guitar performance near the amplifier (Unsplash)”
04 Convex Hull Mask, applied to “Guitar performance near the amplifier (Unsplash)”A complex botanical specimen is highlighted against a dark void. A sharp yellow boundary perfectly demonstrates the algorithm's ability to bridge irregular edges into a single angular polygon.Tim Wright timdwright (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Light Festival (Unsplash)”
05 Convex Hull Mask, applied to “Light Festival (Unsplash)”Multiple jagged green elements are separated into distinct clusters across the frame. Each cluster is encased in its own minimal geometric container, showing how the process handles disjointed selections.Jakub Jacobsky jj_89 (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Blooming pink dahlia (Unsplash)”
06 Convex Hull Mask, applied to “Blooming pink dahlia (Unsplash)”A textured landscape of various shades of green is divided into several clear zones. The largest zone exhibits straight yellow lines that ignore small inward curves to create a simplified outer shell.Melissa Askew teamaskew (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Hiking by the waterfall (Unsplash)”
07 Convex Hull Mask, applied to “Hiking by the waterfall (Unsplash)”A single elongated green shape occupies the center of a pitch-black background. The resulting mask forms a sharp triangular point at the bottom, showcasing the direct connection between the furthest reaches of the pixels.Trent Yarnell tyarnell (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Hellnar Church, Iceland (Unsplash)”
08 Convex Hull Mask, applied to “Hellnar Church, Iceland (Unsplash)”An architectural structure with a prominent steeple is processed into flat color zones. The effect creates a sharp diamond-shaped enclosure for the tower, while the horizontal base is wrapped in a wide, angular polygon.lydia harper lids_harper (photo); processed for the Atlas · CC0 · Wikimedia Commons
Convex Hull Mask, applied to “Sea boat framed by palm trees (Unsplash)”
09 Convex Hull Mask, applied to “Sea boat framed by palm trees (Unsplash)”Intricate foliage patterns are reduced to simplified teal regions on a dark field. Large-scale yellow borders wrap around the topmost clusters, effectively bridging the jagged gaps between individual leaves.Anders Wideskott wideshot (photo); processed for the Atlas · CC0 · Wikimedia Commons

Sources