README

Image size and scaled WebP copies on Tenma. A native plugin decodes, scales and encodes on threads of its own, so a request that converts an image waits in its fiber while the server goes on. Meant for untrusted bytes, such as pictures downloaded from elsewhere: hard limits apply before anything is decoded.

use Tenma\Image\Picture;

[$width, $height, $extension] = Picture::measure($bytes);   // [1200, 1800, 'jpg']
$webp = Picture::webp($bytes, 640);                         // 640 px wide, aspect ratio kept

• Picture::measure($bytes) reads the header alone and returns width, height and the file extension: jpg, png, webp or gif. It runs on the worker thread and takes no fiber.
• Picture::webp($bytes, $width) scales down to $width (never up), keeps the aspect ratio and writes lossy WebP of quality 82; an image with alpha keeps it, a GIF gives its first frame. It runs on the plugin's thread pool, one thread per core, and must be called in a fiber (a request, or Threading\Task).
• Both throw RuntimeException with a message starting image: for bytes that are no supported image or that exceed a limit.

Limits

A file of a few bytes whose header claims 50000 by 50000 pixels fails at the second limit. EXIF orientation is not applied: the pixels come out as stored.

Install

composer require tenma/image
vendor/bin/tenma-image install

The install downloads the plugin of this version for the machine, checks it against its SHA-256 and adds it to tenma.json.

Platforms: macOS arm64, Linux x64 and arm64.

Develop

cd plugin && cargo test && cargo build --release && mkdir -p ../lib
cp target/release/libtenma_image.dylib ../lib/tenma_image.plugin   # .so on Linux
cd .. && composer test && composer stan

The PHP tests run the plugin under a real tenma and skip when tenma or the plugin is missing.

License

The package: MIT or Apache-2.0, at your option. The plugin links libwebp (BSD-3-Clause with a patent grant), built from source; its license is in licenses/libwebp.txt. The Rust crates it is built from are MIT or Apache-2.0.