my $formatter = Spreadsheet::ParseExcel::FmtUnicode->new();
my $workbook = Spreadsheet::ParseExcel::Workbook->Parse($file, $formatter);

foreach my $worksheet ($workbook->worksheets) {
    my ($row_min, $row_max) = $worksheet->row_range;
    my ($col_min, $col_max) = $worksheet->col_range;

    foreach my $row ($row_min .. $row_max) {
        foreach my $col ($col_min .. $col_max) {
            my $cell = $worksheet->get_cell($row, $col);
            next unless $cell;

            # this is what I imagine doing:
            if ($cell->{Type} eq 'pdf') {
                # get the PDF somehow ....
            }
        }
    }
}