wordpress-playground VS libjxl

Sorry friend, WordPress already beat you to it: https://github.com/WordPress/wordpress-playground

> Is there a reason why using OPFS directly from SQLite doesn't work?

I'm guessing this means using SQLite WASM's built-in OPFS integration as described in these articles:

- sqlite3 WebAssembly documentation - Persistent Storage Options: OPFS - https://sqlite.org/wasm/doc/trunk/persistence.md#opfs

- SQLite Wasm in the browser backed by the Origin Private File System - https://developer.chrome.com/blog/sqlite-wasm-in-the-browser...

Within the Playground, SQLite interacts with the database file in MEMFS only, and the Playground coordinates the syncing from MEMFS to OPFS.

https://github.com/WordPress/wordpress-playground/tree/trunk...

The reason for this, I believe, is that the primary use case is/was to have the entire file system in memory, including SQLite's database file. This was the original implementation, and is still the default behavior. Persistence was later added as an optional feature.

The good news is that browser support for OPFS seems to be getting better. From the SQLite docs:

  As of March 2023 the following browsers are known to have the necessary APIs:

One of the most exciting things at WordCamp Europe 2023 for me was discovering how far along the WordPress Playground project is. If you haven’t heard of the playground before, it’s a full version of WordPress, running directly in your browser!

WordPress has an official WebAssembly build for the browser and Node.js: https://developer.wordpress.org/playground https://github.com/WordPress/wordpress-playground

(Disclosure: I'm the creator)

I love the work going on there at WasmLabs, especially enjoying the articles with in-depth technical explorations.

After the article about running WordPress in the browser was published, there's a new project called WordPress Playground which is gradually preparing NPM or Composer packages to make it easier for people to run it.

https://github.com/WordPress/wordpress-playground/

They've been doing very detailed work, like making some patches to PHP and SQLite for improved compatibility with Emscripten, etc. It seems there's a lot of overlap with what WasmLabs has achieved and probably have continued to develop further. Perhaps there's an opportunity for collaboration.

WordPress WASM\ (28 comments)

> Regarding JPEG XL's mobile support, it makes sense it would see limited development if the company that manages one of the biggest mobile players has been the greatest restriction on their success. The lack of support also disincentivises manufacturers to prioritise support.

There was literally no involvement from any hardware vendor in the standardization of JPEG XL. It went from a Call for Proposals in Sept 2018 to Committee Draft in Aug 2019 with very little time for industry feedback. Contrast this with AV1 which had involvement from hardware vendors Intel, NVIDIA, Arm, AMD, Broadcom, Amlogic from the beginning as well as companies who ship media on hardware at scale such as Cisco, Netflix, Samsung and yes Google. These companies reviewed and provided significant feedback on the format that made it suitable for hardware implementation.

https://news.ycombinator.com/threads?id=JyrkiAlakuijala is a lead on the project and a Google employee, and active in JPEG XL development https://github.com/libjxl/libjxl/commits?author=jyrkialakuij...

https://github.com/libjxl/libjxl/blob/main/doc/format_overvi... is a pretty detailed but good overview. The highlights are variable size DCT (up to 128x128), ANS entropy prediction, and chroma from luminance prediction. https://github.com/libjxl/libjxl/blob/main/doc/encode_effort... also gives a good breakdown of features by effort level.

For JPEG XL, refer to its format overview [1]. In short its lossless mode uses a combination of multiple techniques: the rANS coding with an alias table, LZ77, reversible color transforms, a general vector quantization that subsumes palettes, a modified Haar transform and a learnable meta-adaptive decision tree for context modelling.

One good thing about JPEG XL is that its lossy mode also largely uses the same tool, with a major addition of specialized quantization and context modelling for low- and high-frequenty components.

[1] https://github.com/libjxl/libjxl/blob/main/doc/format_overvi...

The cjxl source is here. If you spot any reason why -x strip=exif may not work, tell me.

The problem is that the instructions for actually running the WASM file are not that clear... the docs the author mentions shows how to compile to WASM, which is easy enough, but then here's the instructions to make that actually work in the browser:

https://github.com/libjxl/libjxl/blob/main/tools/wasm_demo/R...

Yeah, you need some mysterious Python script, a JS service worker at runtime, choose whether you want the WASM or WASM_SIMD target, use a browser that supports Threads and SIMD if you chose that, make sure to serve everything with the appropriate custom HTTP headers... just reading that, I can see that to get this stuff working on non-browser WASM targets would likely require expertise in WASM, which is the point of the OP. WASM's UX is just not there yet.

https://github.com/libjxl/libjxl#usage

> Specifically for JPEG files, the default cjxl behavior is to apply lossless recompression and the default djxl behavior is to reconstruct the original JPEG file (when the extension of the output file is .jpg).

I mean compiling a bleeding edge kicad, inkscape or jpeg-xl is easy. But will probably trash your system if you already have an older version installed.

But you look at your image viewer that could have the lossless indicator? (and there is an issue open to add this indicator to the jxl files)

https://github.com/libjxl/libjxl/issues/432