PDF_get_pdi_value()

(PHP 4 >= 4.0.5, PECL pdflib >= 1.0.0)

Get PDI numerical parameter[deprecated]

说明

PDF_get_pdi_value(resource $p,string $key,int $doc,int $page,int $reserved):float

Gets the contents of a PDI document parameter with numerical type.

This function is deprecated since PDFlib version 7, use PDF_pcos_get_number() instead.

If you are having troubles getting the page count make sure you have Root caplitalized correctly.
$numPages=pdf_get_pdi_value($p,"/Root/Pages/Count",$input,0,0);

For keys which are not page-related page must be -1 (in PHP: 0).

From the pdflib manual...
key: Specifies the name of the parameter
doc: a valid PDF document handle retrieved with PDF_open_pdi()
page: A valid PDF page handle (not page number!). For keys which are not page-related page must be -1
Example:
$numPages=pdf_get_pdi_value($p,"/root/Pages/Count",$input,0,0);