Formats

The installers register Mirada for these types, so they list it under “Open With”.

The native codecs

libjpeg-turbo, libwebp, libheif and libjxl are built from source for each platform, at pinned versions, and bundled with Mirada: 3 to 4 MB in all. There is nothing to install, and every machine decodes with the same versions. libheif is built with decoders only (libde265 for HEIC and dav1d for AVIF, linked in), so no encoder, and nothing under the GPL, comes along.

They are fast. libjpeg-turbo decodes a JPEG two to three times faster than Java’s own decoders, and libwebp makes a 24-megapixel WebP about a fifth of a second instead of two.

Before the window is up. For every format but PNG, GIF and BMP, the first image starts decoding while JavaFX is still starting, so a large photo is often ready before the window is.

A missing codec is not fatal. If one of the libraries cannot be loaded (a build from source on a system without it, say), its files are still listed and open with a message naming the library.

Upright

Phones and cameras store the pixels as the sensor read them and write down how the camera was held. Mirada turns every photo upright from that EXIF orientation, the four mirrored ones included. HEIF and JPEG XL say how to turn the picture in their own container as well, and their decoders apply it, so Mirada does not turn them twice.

Colour

Mirada shows pixels as they are stored, as JavaFX does, without applying an embedded colour profile. The exception is JPEG XL, which libjxl converts to sRGB, so it shows in the colours every other format shows in rather than in whatever space it was stored in.

Animation

Animated GIF, WebP, AVIF, HEIC image sequences and JPEG XL play. The first frame shows at once, and every frame decodes on a background thread after it, so stepping onto an animation costs no more than onto a still. An animation past 64 megapixels, its frames counted together, stays a still.

Transparency

Transparent pixels are drawn over a checkerboard.