我有来自Mysql db的这个字符串：
$img_base64_encoded =
'data:image/svg+xml;base64,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'
它在图像中显示“ HI”。现在，我想将此编码图像直接嵌入由TCPDF插件生成的PDF内，但总是会出错：
TCPDF ERROR: [Image] Unable to get the size of the image:
这是插入方法：
$img = '<img src="' . $img_base64_encoded . '">';
$pdf->writeHTML($img, true, false, true, false, '');
我也尝试过：
$pdf->Image('@' . $img_base64_encoded);
存在相同错误。