By default FPDI can "only" handle PDF documents up to PDF version 1.4. Beginning with PDF version 1.5 there were new compression features introduced which involve internal structure changes how a PDF document can be created.
With this seperate parser, as a commercial addon, you're up to date and FPDI will be able to handle PDF documents with a version higher than 1.4 without problems. [More Information](https://www.setasign.com/products/fpdi-pdf-parser/details/)
This Java code was created from PDFBox for converting higher version of PDF to 1.4.
It's easy to apply it on your project which any languages such as PHP, C# etc. You need to execute this command in your language that you use on your project.
java -jar PDFConvert14.jar original.pdf new.pdf
PHP Examples
exec('java -jar PDFConvert14.jar original.pdf new.pdf');
C# Examples
String CMD = "/c java -jar PDFConvert14.jar original.pdf new.pdf";
Process.Start("cmd.exe", CMD);
Copyright (c) 2018 WORAPAT KETENG
Licensed under the MIT License
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