<button class='export-doc k-button'>Export PDF with PNG Format Preserved</button>
<div class="content">
  <img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==" alt="PNG Image"/>
  <p>PNG images will remain in PNG format</p>
</div>
<script>
  $(".export-doc").click(function() {
    kendo.drawing.drawDOM($(".content"))
      .then(function(group) {
        return kendo.drawing.exportPDF(group, {
          keepPNG: true,
          paperSize: "A4"
        });
      })
      .done(function(data) {
        kendo.saveAs({
          dataURI: data,
          fileName: "KeepPNG.pdf"
        });
      });
  });
</script>