File size increased exponentially after embedded png to pdf-doc

[vpatil007]

I have image file that is 2.5MB, after embedding it to pdf file my generated pdf becomes 39 mb. Is this a normal behavior? Or am I doing something wrong?

async getPDFFromImage(pdfObj, dataUrl){
        const pdf = await pdfObj;
        let { width, height, pngDataUrl } = await this.convertToPNG(dataUrl);
        const pdfImageObj = await pdf.pdfDoc.embedPng(pngDataUrl);
        pdf.pdfPage.drawImage(pdfImageObj, {
            x: 0,
            y: position,
            width,
            height
          });
          return pdf.pdfDoc.save();
  }
  
async convertToPNG(dataUrl) {
          const canvas = document.createElement('canvas');
          const context = canvas.getContext('2d');
          const img = new Image();
          img.src = dataUrl;
          let height, width = 0;

        await new Promise((resolve, reject) => {
            img.addEventListener('load', () => {
                height = img.height;
                width = img.width;
                resolve();
            });
            img.addEventListener('error', (message) => {
                reject(message);
            });
        });

        canvas.width = width;
        canvas.height = height;
        context.drawImage(img, 0,0, width,height);
        return {
            pngDataUrl: canvas.toDataURL(this.PNG_MIME_TYPE),
            width,
            height
        };
 }

[bcholmes]

Your code converts the original image to a PNG -- is it possible that that operation is contributing to the increased file size?