Pdfcpu

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Pdfcpu
A Go library and command line tool for PDF processing incl. validation
Homepage:https://pdfcpu.io/
License:Apache-2.0 License
Function:Validation,Metadata Extraction
Content type:Document
Appears in COW:Validation Error Analysis and Treatment for PDF-hul 122 Invalid destination - Destination NULL, Validation Error Analysis and Treatment for PDF-hul 133 Invalid date




Description

pdfcpu is a powerful Go library and command line tool that supports many PDF processing functions such as reading and writing the xref table, extracting images, fonts and embedded file attachments and encryption detection as well as decryption. A full list of the command set is avaiable at: https://pdfcpu.io/about/command_set

Validation

pdfcpu validates PDFs up to version 1.7. There are two different levels of validation, strict and relaxed, and the option to run validation in verbose mode which shows the output of the entire PDF syntax.

pdfcpu validate -mode strict this.pdf
validating(mode=strict) this.pdf ...
validation error (try -mode=relaxed): dict=type1FontDict required entry=FirstChar missing
pdfcpu validate -mode relaxed this.pdf
validating(mode=relaxed) this.pdf ...
validation ok

Metadata Extraction

Extraction of Metadata is possible in two ways. The argument info prints Information such as title, author, PDF producer, creation / modification data and some technical metadata such as encryption and permission information and whether the PDF is tagged, linearized or includes watermarks. Sample output:

pdfcpu info this.pdf
        PDF version: 1.6
         Page count: 96
          Page size: 21.00 x 29.70 cm
   .........................................
              Title: This is just a test
             Author: Digiman
            Subject: 
       PDF Producer: Adobe PDF Library 15.0
    Content creator: Adobe InDesign CC 207 (Macintosh)
      Creation date: D:20190912181416+02'00'
  Modification date: D:20190918120753+02'00'
           Keywords: key1
                     key2
   ..........................................
             Tagged: Yes
             Hybrid: No
         Linearized: No
 Using XRef streams: Yes
 Using object streams: Yes
         Watermarks: No
   ..........................................
          Encrypted: No
        Permissions: Full access

The second option is to extract any embedded metadata via the extract -mode meta flags. This creates txt files with the extracted metadata entries in a specified directory. Sample output:

pdfcpu extract -mode meta this.pdf mdout
  extracting metadata from this.pdf into mdout/ ...
  writing mdout\this_Metadata_XObject_6499_6500.txt
  writing mdout\this_Metadata_unknown_401_33.txt
  writing mdout\this_Metadata_XObject_292_289.txt
  writing mdout\this_Metadata_Catalog_6455_385.txt
  writing mdout\this_Metadata_XObject_291_290.txt
  writing mdout\this_Metadata_unknown_6491_6475.txt


User Experiences

Development Activity

pdfcpu has an active user and developer community. All activity can be viewed via the github repo: https://github.com/pdfcpu/pdfcpu