Tessera (tessera v0.1.0)

Tessera generates DZI (Deep Zoom Image) tile pyramids from input images and renders them in a Phoenix LiveView via OpenSeadragon.

Two pieces

Tessera.generate/3 — given an input image path and an output directory, shells out to ImageMagick to produce a DZI manifest and tile pyramid.
Tessera.viewer/1 — a Phoenix function component that renders an OpenSeadragon viewer pointed at a DZI manifest URL.

Quick start

# Server-side: produce tiles
{:ok, %{manifest: manifest, tiles_dir: _}} =
  Tessera.generate("/uploads/photo.jpg", "/var/www/dzi")

# LiveView: render the viewer
~H"""
<Tessera.viewer id="photo" src="/dzi/photo.dzi" />
"""

The viewer also accepts plain image URLs (.jpg, .png, etc.) for basic pan + zoom without generating tiles:

~H"""
<Tessera.viewer id="thumb" src="/uploads/photo.jpg" />
"""

See Tessera.TileGenerator and Tessera.Viewer for full details.

Requires ImageMagick (magick binary) on the host PATH for tile generation, and tessera.js (in priv/static/) wired into the parent app's LiveSocket hooks for the viewer.