erwanvivien/fast_qr

Ultra fast QRCode generation

fast_qr's Issues

After upgrading to 0.8.3, I get index out of bounds: the len is 0 but the index is 0

In my project miniserve, I get errors from inside fast_qr since upgrading to 0.8.3: https://github.com/svenstaro/miniserve/actions/runs/4175872918/jobs/7231388083

I believe this is a bug recently introduced in fast_qr itself.

FYI: AGPL licensing

This is a nice library, and fast too (I ran my own benchmarks as well) :) Sadly I cannot use it for work due to its AGPL license.

You probably know that AGPL requires modified code to be shared with the public and remain under the AGPL license. Also any code linked to the GPL/AGPL code (either dynamically or statically) is considered a combined work and the entire combination must be licensed under GPL/AGPL. So the code I write for work would also have to be open sourced as GPL/AGPL.

Sadly my employer won't want to share the rest of our codebase that might use this library.

Why is `Shape::Command` disabled on wasm?

I'm developing a project that is compiled to wasm (cloudflare worker) and needs to generate qr codes with custom visual processing when converting to an image. I've completed the processing using the command shape variant, but now I need to use it in wasm.

Why is it disabled for wasm? I don't think there are any issues preventing it being enabled, as it's just a function pretty much.

An explanation would be appreciated, or a patch to remove the disabling on wasm arch.

How can I get byte from qrcode image?

I can see to_file but in my case I will need byte as a http response from_byte for a return but can't find anyway to do it.

Image branding

Hey, just wanna know if there is wayt to brand the QR code generated, like colors and logo.

Add customization of error code level (ecl)

At the moment fast_qr (javascript/wasm interface) always uses the default error code level (ecl) of Q (25%). It would be desirable if this can be configured through SVGOptions.

e.g.

const options = new SvgOptions()
  .ecl(ECL.Q);

1.57 const panics

Remove most Option to use panic instead

Exception of QR code generated by specific length data

e.g.

200505150001

NodeJS support?

Would be nice if this library also worked in NodeJS, since there are no functioning qrcode generation libraries with high performance for NodeJS right now

Transparent backgrounds

First of all, great crate, I'm using it in a Discord bot.

Discord has 2 themes, dark and light. I would want to use a module color that fits both dark and light, but in order to do that, I need transparent backgrounds.

In your opinion, how hard would that be to make? I looked into the SVG this crate worked with, but didn't see any transparency options at first glance.

If in your opinion it shouldn't be so hard, I might want to take a stab at it :)

Make wasm-bindgen optional

This crate, as of the time of writing, only has a single dependency (wasm-bindgen) which is great! But I wonder whether even this dependency could be made optional for those of us who don't need wasm-bindgen.

QR Codes are Diagonally Inverted When Rendered as SVGs/PNGs

Hey! Big fan of the library, though I came across a strange issue the other day.

Seems as though the QR codes are rendered with a diagonal inversion for image/svg output.

This can be verified by looking at the format information (as per ISO/IEC 18004 2015), specifically the first two error correction bits and their placement.

This diagram from Wikipedia summarizes the expectations of the format sequence.
https://en.wikipedia.org/wiki/File:QR_Format_Information.svg

---

I used this snippet to create the QRCode for the following tests:

    let qrcode = QRBuilder::new("Test")
        .ecl(ECL::M)
        .version(Version::V01)
        .build()
        .unwrap();

With an ECL::M, we expect to see the ECL sequence of [1,0].

In the following images, the red and blue borders highlight the format sequences, with the green highlighting the ECL sequence.

When printing to our terminal, we see the format sequences aligned correctly:

However, when rendering an SVG or PNG, we notice the diagonal inversion, causing inversion of the format sequences:

Note that the rest of the QR code is also diagonally inverted.

Benchmarking fails in ubuntu

Benchmarking fails in ubuntu with below error:

vscode ➜ /workspaces/fast_qr (master) $ /bin/python3.11 /workspaces/fast_qr/benches/bench.py
| Benchmark                | Lower     | Estimate  | Upper     |                          |
|:------------------------ |:---------:|:---------:|:---------:| ------------------------ |
Traceback (most recent call last):
  File "/workspaces/fast_qr/benches/bench.py", line 90, in <module>
    f"| {test2:<24} | {data2[0]:<9} | {data2[1]:<9} | {data2[2]:<9} |",
                       ~~~~~^^^
IndexError: list index out of range

After debugging found that microsecond is represented as u instead of unicode char µ. This is not helping to extract microseconds value from the output of criterion benchmark.

Support for terminals with light backgrounds

Thank you for your work！
I want to replace qrcode with your crate, Is it possible to implement like this for supports both dark and light colored terminals

    let code = QrCode::new("mow mow").unwrap();
    let image = code.render::<unicode::Dense1x2>()
        .dark_color(unicode::Dense1x2::Light)
        .light_color(unicode::Dense1x2::Dark)
        .build();
    println!("{}", image);

unresolved import `fast_qr::convert::image` could not find `image` in `convert`

problem

• unresolved import fast_qr::convert::image could not find image in convert

windows 10

rustc version is rustc 1.66.0-nightly (06f049a35 2022-10-17)

dependencies

[dependencies]
pyo3 = { version = "0.17.3", features = ["extension-module"] }
fast_qr="0.6.1"

QR generated with V40 ImageBuilder with Pixmap generates Garbled PNG image

High. I was trying to generate a QR as a PNG to I could integrate it into a an tag on a webassembly module I' building but every single time in generates a garbled image. I don't know what step I'm missing to do over the produced [u8] so align the data of if it is in reality an issue with a dependency.

The shortest example I can provide is:

Cargo.toml

[package]
name = "foo"
version = "0.1.0"
authors = ["Rust Example <[email protected]>"]

[dependencies]
fast_qr = { version = "0.8.4", features = ["image"] }
base64 = "0.21.0"

main.rs

use fast_qr::{
    convert::{image::ImageBuilder, Builder},
    QRBuilder, Version, ECL,
};


fn main() {
    

    let qrcode = match QRBuilder::new("datos de prueba para salir".to_string().as_bytes())
        .ecl(ECL::H)
        .version(Version::V40)
        .build() {
	    Ok(qr) => qr,
	    Err(why) => {
		panic!("Failed generating Qr Code: {why:?}");
	    }
	};

    let pixmap = ImageBuilder::default()
        .background_color([255, 255, 255, 0]) // transparency
        .to_pixmap(&qrcode);

    let Ok(url_encoded_data)  = pixmap.encode_png().map(|x| base64::encode(&x[..]) ) else {
	panic!("could not base64 encode generated QR from string '");
    };

    let src = format!("data:image/png;base64,{url_encoded_data}");

    println!("{src}");

    
}

The print at the end produces the URL encoded data that is supposed to be used on the tag

data:image/png;base64,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

The image can be downloaded from here : https://ibb.co/Y3n4q5T

I'll appreciate any guidance on the topic

Remove `Cargo.lock`

According to the Cargo book

If you’re building a non-end product, such as a rust library that other rust packages will depend on, put Cargo.lock in your .gitignore.

I came across an issue while upgrading to 0.8.0 because I also required png = "0.17.7" while fast_qr lists png = "0.17.6".

In my case it doesn't matter but this could cause future annoyance (or actual issues) to someone else. Perhaps we should remove main.rs and put the contained code into an examples directory (which you can run easily with cargo).

I could make a pr for this if you agree sometime soon-ish :)

wasm-bindgen feature

For use via wasmi, wasm-bindgen is a problem, would you consider putting it behind a feature? If it's straightforward I could probably even find time to create a PR if you're interested, I have a temporary fix in my fork here

implement error trait for QRCodeError struct

It would be nice if std::error::Error is implemented for QRCodeError struct. It will be easy for error handling.

Add title to SvgOptions

It would be nice if the SvgOptions class adds an optional 'title' property. If set, the title would then be added as a child of the rect element:

<rect ... fill="#ffffff">
  <title>title</title>
</rect>

The title will be shown as a tooltip when the mouse hovers over the element. See:
https://developer.mozilla.org/en-US/docs/Web/SVG/Element/title
demo:
https://stackoverflow.com/questions/10643426/how-to-add-a-tooltip-to-an-svg-graphic

Prints top margin

fast_qr/src/helpers.rs

Lines 31 to 37 in 11fc725

	print!("{}", BOTTOM);
	print_line(
	&[Module::empty(true); 177],
	&[Module::empty(false); 177],
	qr.size,
	);
	println!("{}", BOTTOM);

Is this paragraph for beauty? Because I think the following code should be faster

// Prints top margin without background
    println!("{}", BOTTOM.to_string().repeat(qr.size + 2));