How to output a PDF/A-3 file using the TCPDF library

[f8solution]

Hello,

I am able to use the library correctly and generate a PDF file. However, if I understand correctly, the TCPDF library does not currently support direct output in the PDF/A-3 format (only PDF/A1-b).

Is an update planned to incorporate the choice of the output format?

If not, do you know how I can convert the file after the output command, using PHP to achieve PDF/A-3?

php code
// Save the PDF in the temporary folder
$err .= $pdf->Output($filePath, 'F');

Thank you in advance for your answer.

Best regards,