Error determining page count - fixable with change to grep command?

[abali96]

On rare occassions, I've encountered PDFToImage::PDFError: Error determining page count..

Working off of what's found on this line, https://github.com/robflynn/pdftoimage/blob/master/lib/pdftoimage.rb#L95, you can see for this particular document pdfinfo does in fact return a page count:

pdfinfo /tmp/document.pdf
Title:           Document
Author:          https://imagemagick.org
Creator:         https://imagemagick.org
Producer:        https://imagemagick.org
CreationDate:    Fri Sep 15 11:17:09 2023 PDT
ModDate:         Fri Sep 15 11:17:09 2023 PDT
Custom Metadata: no
Metadata Stream: no
Tagged:          no
UserProperties:  no
Suspects:        no
Form:            none
JavaScript:      no
Pages:           1
Encrypted:       no
Page size:       611.242 x 791.252 pts (letter)
Page rot:        0
File size:       117406 bytes
Optimized:       no
PDF version:     1.4

However, when we add | grep Pages, it returns:

pdfinfo /tmp/document.pdf | grep Pages
Binary file (standard input) matches

It seems like changing grep Pages to grep --text Pages or grep -a Pages fixes matters, but I'm not sure if there's a reason why that shouldn't be used by default.

For reference:

pdfinfo version 23.10.0
Copyright 2005-2023 The Poppler Developers - http://poppler.freedesktop.org
Copyright 1996-2011, 2022 Glyph & Cog, LLC

I'm running on MacOS 14.0.

Thanks!

[abramovks]

My solution. Replace function and add -a key to Grep

pdf2image = PDFToImage

            def pdf2image.page_size(filename, page)
                cmd = "pdfinfo -f #{page} -l #{page} #{Shellwords.escape(filename)} | grep -a Page"
                output = exec(cmd)
    
                matches = /^Page.*?size:.*?(\d+).*?(\d+)/.match(output)
                if matches.nil?
                    raise "Unable to determine page size."
                end
    
                scale = 2.08333333333333333
                dimension = {
                    width: (matches[1].to_i * scale).to_i,
                    height: (matches[2].to_i * scale).to_i
                }
    
                dimension
            end
    
            def pdf2image.page_count(filename)
                cmd = "pdfinfo #{Shellwords.escape(filename)} | grep -a Pages"
                output = exec(cmd)
                matches = /^Pages:.*?(\d+)$/.match(output)
                if matches.nil?
                    raise "Error determining page count."
                end
    
                return matches[1].to_i
            end