Add a mirror reflection to an image

A reflection is the picture’s edge, reflected about that edge and faded out. The page builds exactly that: it takes the rows nearest the edge you cast from, reflects them so the first reflected row touches the last picture row, and multiplies the copy’s transparency by a ramp that starts at your opacity and reaches nothing where you say it should. The original picture is not touched; the frame simply grows to hold the reflection. Colour is never darkened or tinted — what looks like a darker reflection is the background showing through it.

Two presets cover most uses. Glossy floor reflects 40 % of the picture at 45 % opacity, fading to nothing at its end — the look of a product photographed on a polished surface. Still water leaves a two-pixel gap, reflects the full height at 60 % and fades more slowly, which reads as a lake or a wet street. A ripple can be added to water; it is off by default because it resamples.

1. 1Open the picture. A product cut-out on a transparent PNG gives the cleanest result, but any picture works.
2. 2Choose floor or water. Glossy floor casts 40 % of the picture at 45 % opacity, fading out. Still water reflects the whole height after a two-pixel gap, a little stronger.
3. 3Tune the reflection. Cast it below, above or to either side; set the gap, how much is reflected, the opacity where it meets the picture and where it fades to nothing. Add a ripple for water if you want one.
4. 4Save as PNG. A clear background stays clear in PNG or WebP. JPEG has no transparency and fills it — white, black or a colour you choose.

A 1200 × 1200 transparent PNG of a bottle with the floor preset becomes 1200 × 1680. Row 1200 of the output is row 1199 of the picture at 45 % of its opacity; row 1439, halfway down the reflection, is row 960 at about 22 %; the last row is fully transparent. Switching to still water makes it 1200 × 2402 — a two-pixel gap and 1200 reflected rows. Saved as PNG, the bottle itself is the source’s pixels, unchanged.

• It reflects the whole edge. Anything touching the edge — a shadow, a table, a background — is reflected too. A cut-out on a clear background gives the cleanest result.
• No perspective. A real floor reflection of a tilted object would be foreshortened. This is a straight reflection, which suits front-on product shots.
• JPEG flattens the fade. Transparency has to become a colour in a JPEG; choose PNG or WebP to keep it.
• Ripple resamples. With the ripple on, reflected lines are shifted by fractions of a pixel.

How big does the picture get?

Taller (or wider, for a side reflection) by the gap plus the reflection's length. A 1200 × 1200 picture with the floor preset becomes 1200 × 1680: 480 rows of reflection at 40 %.

Is the reflection a real mirror copy?

Yes. The rows nearest the picture are its own edge rows, reflected; the fade is applied to the copy's transparency, not to its colours. Without a ripple, every reflected pixel is an exact copy of its partner above, made more transparent.

What does the ripple do?

It shifts each line of the reflection sideways along a slow wave that lengthens with distance, the way a breeze breaks a reflection in water. The shifts are fractions of a pixel, so the reflection is resampled when the ripple is on; it is off by default.

Why does my reflection look grey in a JPEG?

JPEG cannot store transparency, so the fading reflection is blended onto the fill colour — white by default. Save as PNG to keep it transparent, or choose a fill that matches the page it is going on.

Can I reflect upwards or sideways?

Yes — cast from below, above, left or right. A side reflection suits a product photographed against a mirror wall.