Parsing through PDF file and separating pages based on placeholder

I have a large amount of documents that are getting scanned into a folder via a high capacity scanner.

I' have created a barcode generator in PHP that are placed manually between each document.

I'm looking for a solution in PHP that would open this large PDF file, and at each barcode page, create a new PDF file based on the timestamp.

The end result would hopefully be me having 10 separate files with the barcode page being the first page in each document, rather than my one big document.

Thanks in advance.