Image Vignette
Darken the corners with an elliptical vignette.
Overview
The Image Vignette tool darkens the corners of an uploaded picture with a soft elliptical falloff, drawing the eye toward the centre and giving the frame a classic film-camera feel. Upload a photo, set the vignette strength and the tool returns a re-encoded copy with the darkening baked in.
It is the right effect for moody portrait edits, vintage-style social posts, hero photography that needs to spotlight a subject, and any time you want to crop the viewer's attention without literally cropping the image. The look is also useful for product shots where you want the eye to land on the centre rather than wander to the edges.
How it works
A 2-D radial gradient is computed across the canvas: at the centre the gradient is 1.0 (no change), at the corners it falls to a configurable minimum (often 0.3 or so). The falloff follows an ellipse matching the image's aspect ratio rather than a circle, which is what gives the result a natural cinematic feel rather than a comic-book vignette.
Each pixel's red, green and blue channels are multiplied by the gradient value at that position. Multiplication ensures that highlights desaturate toward black smoothly and that no channel ever exceeds its original value — the effect is purely darkening, never lightening. An optional inner-radius parameter controls how much of the centre stays untouched before the falloff begins.
Examples
Before: portrait.jpg (sharp, evenly lit)
After: portrait-vig.jpg with strength 0.4 — corners darkened by 60%,
face fully bright.
Before: landscape.jpg (bright sky in corners)
After: landscape-vig.jpg with strength 0.6 — clouds preserved,
edges fall to near-black.
Before: product-shot.jpg (white background)
After: product-vig.jpg with strength 0.3 — subtle radial halo,
product still in focus.
FAQ
Is the vignette elliptical or circular?
Elliptical by default — it tracks the image's aspect ratio so a 16:9 photo gets a 16:9 vignette. Circular vignettes look unnatural on non-square frames.
Will the corners go pure black?
Only if you set the minimum to zero. Most cinematic vignettes leave the corners at 30-50% brightness so the result still reads as photographic.
Can I lighten instead of darken?
The bundled implementation only darkens. A "white vignette" would invert the gradient and blend toward white — that requires a separate compositing step.
Does the vignette move with crops?
No — the gradient is computed against the final output dimensions. Crop first, then apply the vignette to keep the falloff centred on the visible content.
Will JPEG re-encoding ruin the smooth gradient?
A gentle gradient survives JPEG quality 85+ without visible banding. At lower qualities you may see contour lines near the falloff; PNG output avoids that issue entirely.