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libjxl | glibc | |
---|---|---|
84 | 25 | |
2,209 | 1,228 | |
32.1% | - | |
9.8 | 0.0 | |
1 day ago | over 5 years ago | |
C++ | C | |
BSD 3-clause "New" or "Revised" License | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
libjxl
- JPEG XL Reference Implementation
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JPEG XL and the Pareto Front
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.
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Compressing Text into Images
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...
- JPEG XL v0.9.0 Released
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Stripping Metadata
The cjxl source is here. If you spot any reason why -x strip=exif may not work, tell me.
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Www Which WASM Works
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.
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First automatic JPEG-XL cloud service
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).
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Why "sudo make install"?
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.
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XYB JPEG: Perceptual Color Encoding Tested
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
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Heyo Everyone! - is there a win or mac software to batch convert imgs to avif?
You might want to use libjxl directly, e.g. for visually lossless images: cjxl --effort 9 --brotli_effort 11 --distance 1.0 --num_threads (nproc) --lossless_jpeg 0 input.png output.jxl on linux (if you're on windows/mac, just replace the (nproc) with the number of cpu threads you have, e.g. --num_threads 16).
glibc
- `Strlen` in Glibc
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How does sqrt() work in glibc?
I am writing a short paper for school and the topic is Fast Inverse Square Root and alternatives. One of the questions is how the sqrt-function is implemented in glibc. Here is the code of that function.
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A collection of lock-free data structures written in standard C++11
The code isn't the easiest to read but in glibc it seems that the syscall is only performed if waiter are detected in userspace during an unlock operation
https://github.com/lattera/glibc/blob/master/nptl/pthread_mu...
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Converting my new code (Bytearray2Float64) into 19 Programming Language
You might still not realize, but floats are a large topic. Have a look at eg. this implementation here: https://github.com/lattera/glibc/blob/master/stdlib/strtod_l.c
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Honest question about this "The byte order fallacy" blog post.
This is a nice write up, thank you. However, I'm stilling interpreting this as a "fun trick" rather than the common sense method for solving the problem. For example, looking at the source code for htonl() from glibc: https://github.com/lattera/glibc/blob/master/inet/htonl.c
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Dio deleted the tweet shortly after
Second of all: The horrifying truth is that there is no such thing as a canonical text representation for IPv4 (source) (and yes... I am indeed citing the failed attempt to standardize this as my source for it not being standardized). Authoritatively speaking, all possible (non-binary) representations are equally invalid. In fact, text address resolution is typically delegated to the OS kernel, so what constitutes a "usable" address is liable to vary depending on if you're using Linux, OSX, Windows, or Other.
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Discussion Thread
Optimized code gets really weird. The creators of strlen, for example, decided that iterating over each character to find the end was far too slow. So instead, they convert the character pointer into an int pointer and do bitwise manipulation with the int on two different magic numbers so they can check four/eight characters at once.
- Tengo una duda en algo C/C++
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How does jvm deal with syscalls
If you're using a cross-platform C compiler like gcc or clang, you're usually expected to switch to assembly. Here's the syscall instruction in glibc
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Math Functions with -nostdlib
Maybe you should include the math part of a libc statically with your code. glibc is one option, or dietlibc if you want it to be as small as possible.
What are some alternatives?
qoi - The “Quite OK Image Format” for fast, lossless image compression
DirectXMath - DirectXMath is an all inline SIMD C++ linear algebra library for use in games and graphics apps
Android-Image-Filter - some android image filters
fastapprox - Approximate and vectorized versions of common mathematical functions
openlibm - High quality system independent, portable, open source libm implementation
libavif - libavif - Library for encoding and decoding .avif files
nixpkgs - Nix Packages collection & NixOS
jxl-migrate - A simple Python script to migrate images to the JPEG XL (JXL) format
illumos-gate - An open-source Unix operating system
squoosh - Make images smaller using best-in-class codecs, right in the browser.
crux - General purpose bitemporal database for SQL, Datalog & graph queries. Backed by @juxt [Moved to: https://github.com/xtdb/xtdb]