如何从元数据中找到 PDF 的标题？

Question

How can I get the title for a PDF file after having renamed the file itself?

PSPath              : Microsoft.PowerShell.Core\FileSystem::/home/nicholas/to/99.pdf
PSParentPath        : Microsoft.PowerShell.Core\FileSystem::/home/nicholas/to
PSChildName         : 99.pdf
PSDrive             : /
PSProvider          : Microsoft.PowerShell.Core\FileSystem
PSIsContainer       : False
Mode                : -----
ModeWithoutHardLink : -----
VersionInfo         : File:             /home/nicholas/to/99.pdf
                      InternalName:     
                      OriginalFilename: 
                      FileVersion:      
                      FileDescription:  
                      Product:          
                      ProductVersion:   
                      Debug:            False
                      Patched:          False
                      PreRelease:       False
                      PrivateBuild:     False
                      SpecialBuild:     False
                      Language:         
                      
BaseName            : 99
Target              : 
LinkType            : 
Length              : 592483
DirectoryName       : /home/nicholas/to
Directory           : /home/nicholas/to
IsReadOnly          : False
FullName            : /home/nicholas/to/99.pdf
Extension           : .pdf
Name                : 99.pdf
Exists              : True
CreationTime        : 2/19/2021 11:45:18 PM
CreationTimeUtc     : 2/20/2021 7:45:18 AM
LastAccessTime      : 2/20/2021 2:02:36 AM
LastAccessTimeUtc   : 2/20/2021 10:02:36 AM
LastWriteTime       : 2/19/2021 11:45:18 PM
LastWriteTimeUtc    : 2/20/2021 7:45:18 AM
Attributes          : Normal


PS /home/nicholas/to> 
PS /home/nicholas/to> Get-ChildItem -Path ./ –File | Select-Object -Property *

This is to bulk import PDF files into calibre , which, notably, seems to recognize duplicates and even displays some titles. Is it parsing the PDF file itself, or gleaning this from meta -data?

Answer 1

For this, you can use pdfinfo.exe which you can find as part of the free Xpdf command line tools .

After you have downloaded and extracted the zip file, copy pdfinfo.exe to some directory and make sure you unblock it, either by right-click or by using PowerShell

Unblock-File -Path 'Where\Ever\You\Have\Copied\It\To\pdfinfo.exe'

Using that, to get the original title as stored in the pdf, you do

$title = ((& 'D:\Test\pdfinfo.exe' 'D:\Test\test.pdf' | 
    Where-Object { $_ -match '^Title:' }) -split ':', 2)[-1].Trim()