Implement your own PDF processing in SearchWP

gistfile1.php

<?php

function my_searchwp_external_pdf_processing( $content, $filename, $post_id ) {
    if( class_exists( 'My_Awesome_PDF_Parser' ) ) {
        $parser = new My_Awesome_PDF_Parser();
        $content = $parser->extract_text_from_pdf( $filename );
    }
    return $content;
}

add_filter( 'searchwp_external_pdf_processing', 'my_searchwp_external_pdf_processing', 10, 3 );