Reflection
The reflection parameters mirror the image onto a glossy floor beneath it, fading and softening with distance. This is the polished-surface product shot, and it works on its own or alongside any drop shadow.
The canvas grows downward by the reflection’s length, and sideways by 3 x reflection-blur. Use reflection-bounds=clip to keep the original output size instead.
Each separate object in the image gets its own reflection line, so a bottle and a ball standing side by side each meet their own reflection rather than sharing one. An opaque photograph, having no separate objects, reflects as a rectangle.
Order, back to front: bg, the shadow, the reflection, then the picture.
Reflections are not drawn on video.
Notes
drop-shadow-output=shadowkeeps the reflection in its output.provenance=c2parecords a reflection as an edit.
From Photo to Product Shot
The example below starts from a product photographed on a colored backdrop. bg-remove cuts the subject out, drop-shadow-type=cast throws a shadow along the floor, and reflection mirrors the subject onto it, all in one URL.
