cpdf_add_outline

<?php
$cpdf = cpdf_open(0);
cpdf_page_init($cpdf, 1, 0, 595, 842);
cpdf_add_outline($cpdf, 0, 0, 0, 1, "Page 1");
// ...
// some drawing
// ...
cpdf_finalize($cpdf);
Header("Content-type: application/pdf");
cpdf_output_buffer($cpdf);
cpdf_close($cpdf);
?>