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Contrast

Function that, given an RGB image and a factor, returns an RGB image with the contrast changed by the given factor along an S-Curve.

Syntax​

changeContrast(image, factor)

Parameters​

  • image : HTMLImageElement
    The image element to change the contrast of.

  • factor : number
    The contrast adjustment factor (-100 to 100):

    • factor > 0: the image contrast gets increased by the factor.
    • factor < 0: the image contrast gets decreased by the factor.
    • factor = 0: the image does not change.

Return​

  • Promise : Promise<HTMLImageElement>
    A promise that resolves with the image element with adjusted contrast.

Throws​

  • Error
    Thrown if the specified contrast factor is outside the valid range.

Examples​

const editpix = new EditPix();

// image url
const url = "images/img.jpg";

// crate image
var image = new Image();
image.src = url;

// waiting image load
image.onload = () => {
    // change image contrast
    editpix.changeContrast(image, 2)
        .then(resultImage => {
            // render modified image
            document.body.appendChild(resultImage);
        })
        .catch(error => { console.log(error) })
}