How to Add Image From Canvas When Generating PDF in JavaScript

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This sample demonstrates how to add image from canvas during PDF generation in JavaScript with BytescoutPDF.js (Bytescout PDF Generator for JavaScript).

// function that creates BytescoutPDF instance (defined in BytescoutPDF.js script which have to be included into the same page)
// then calls API methods and properties to create PDF document
// and returns created BytescoutPDF object instance
// this CreatePDF() function is called from Sample.html

function CreatePDF() {

    // create BytescoutPDF object instance
    var pdf = new BytescoutPDF();

    // set document properties: Title, subject, keywords, author name and creator name
    pdf.propertiesSet("Sample document title", "Sample subject", "keyword1, keyword 2, keyword3", "Document Author Name", "Document Creator Name");

    // set page size
    pdf.pageSetSize(BytescoutPDF.A4);

    // set page orientation (BytescoutPDF.PORTRAIT = portrait, BytescoutPDF.LANDSCAPE = landscape)
    pdf.pageSetOrientation(BytescoutPDF.PORTRAIT);

    // add new page
    pdf.pageAdd();

    // create temporary canvas (you can also simply get existing canvas)
    var canvas = document.createElement('canvas');
    // set width and height
    canvas.width = 320;
    canvas.height = 240;

    // get context from canvas (to draw on)
    var context = canvas.getContext("2d");

    // set white background color
    context.fillStyle = "#FFFFFF";
    // and fill the background with white color
    context.fillRect(0, 0, 320, 240);

    // draw the yellow circle
    context.strokeStyle = "#000000";
    context.fillStyle = "#FFFF00";
    context.beginPath();
    context.arc(100, 100, 50, 0, Math.PI * 2, true);
    context.closePath();
    context.stroke();
    context.fill();

    // load image from canvas into BytescoutPDF
    pdf.imageLoadFromCanvas(canvas);

    // place this image at given X, Y coordinates on the page
    pdf.imagePlace(20, 40);


    // return BytescoutPDF object instance
    return pdf;
}

Generated PDF file with image from canvas (click to view full size):

Click to view full size

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