About: http://www.hsluv.org

Installation

If you are using Maven, add the following to your pom.xml file:

<dependency>
    <groupId>org.hsluv</groupId>
    <artifactId>hsluv</artifactId>
    <version>1.0.1</version>
</dependency>

Usage

The API is designed to avoid heap allocation. The HSLuv class defines the following public fields:

• RGB: hex:String, rgb_r [0;1], rgb_g [0;1], rgb_r [0;1]
• CIE XYZ: xyz_x, xyz_y, xyz_z
• CIE LUV: luv_l, luv_u, luv_v
• CIE LUV LCh: lch_l, lch_c, lch_h
• HSLuv: hsluv_h [0;360], hsluv_s [0;100], hsluv_l [0;100]
• HPLuv: hpluv_h [0;360], hpluv_p [0;100], hpluv_l [0;100]

To convert between color spaces, simply set the properties of the source color space, run the conversion methods, then read the properties of the target color space.

Use the following methods to convert to and from RGB:

• HSLuv: hsluvToRgb(), hsluvToHex(), rgbToHsluv(), hexToHsluv()
• HPLuv: hpluvToRgb(), hpluvToHex(), rgbToHpluv(), hexToHpluv()

Use the following methods to do step-by-step conversion:

• Forward: hsluvToLch() (or hpluvToLch()), lchToLuv(), luvToXyz(), xyzToRgb(), rgbToHex()
• Backward: hexToRgb(), rgbToXyz(), xyzToLuv(), luvToLch(), lchToHsluv() (or lchToHpluv())

For advanced usage, we also export the bounding lines in slope-intercept format, two for each RGB channel representing the limit of the gamut.

• R < 0: r0s, r0i
• R > 1: r1s, r1i
• G < 0: g0s, g0i
• G > 1: g1s, g1i
• B < 0: b0s, b0i
• B > 1: b1s, b1i

Example:

HsluvColorConverter conv = new HsluvColorConverter();
conv.hsluv_h = 10;
conv.hsluv_s = 75;
conv.hsluv_l = 65;
conv.hsluvToHex();
System.out.println(conv.hex); // Will print "#ec7d82"
float r = Math.max(0, (float) conv.rgb_r);
float g = Math.max(0, (float) conv.rgb_g);
float b = Math.max(0, (float) conv.rgb_b);
var color = new java.awt.Color(r, g, b);
// For Android
var color = android.graphics.Color.rgb(r, g, b);

Testing

mvn test

Deployment

Releases are published to Maven Central by the release.yml workflow, triggered by a v* tag.

One-time setup: generate a Portal token at https://central.sonatype.com, then store the credentials as repo secrets:

gh secret set GPG_PRIVATE_KEY --repo hsluv/hsluv-java < signing-key.asc
gh secret set GPG_PASSPHRASE --repo hsluv/hsluv-java --body "<passphrase>"
gh secret set CENTRAL_TOKEN_USERNAME --repo hsluv/hsluv-java --body "<token username>"
gh secret set CENTRAL_TOKEN_PASSWORD --repo hsluv/hsluv-java --body "<token password>"

Then bump the version in pom.xml and create a release:

gh release create v1.0.1 --generate-notes