Windows 10: How to compress PDF file size?

I have generated pdf's using rdlc and then combine multiple pdf files to single document using itextsharp pdfsmartcopy class. But my pdf size is large, i want to reduce the size of pdf. I have tried compression using itextsharp but that's unable to compress. When i upload the pdf to ilivepdf.com online for compression then it compress 21MB file to 1MB.



***Modified title from: PDF resize generated using rdlc and itextsharp***

:)

 

Compress PDF files

File Explorer will still show the original size of the file. To see how much it has shrunk, right-click on it and select 'Properties'. This shows two sizes, the important one is the 'Size on disk' which should now be smaller that the file size. How much smaller depends on how easy it is to compress that pdf, some will compress more than others.

 

Compress PDF files

Do you want to compress without loosing any quality, or would you accept a lower quality and/or resolution?

Images in pdfs can be saved in a lossless form or use jpeg compression, for jpegs the level of compression can be increased at the cost of some loss of quality. The image resolution could also be reduced to save space. Any compression software would likely use these techniques to reduce the size of the file. Whether you notice the difference would depend on how heavily the compression was applied.

For compression that leaves the original file untouched there are two options in Windows itself - ntfs file compression or 'send to a compressed (zipped) folder'. If you have Libre Office or similar you already have software that can open a pdf for editing and export it in a lower quality form.

As an experiment I downloaded an illustrated manual in pdf form. The original file size was 17.2MB.

ntfs compression:
Right-click on file, select properties, click the 'Advanced...' button and tick 'compress contents to save disk space'.
After compression File Explorer still shows the original file size, but its Properties shows 'size on disk: 16.4MB'. The data in the file is unaltered and the file can be opened as normal.

Send to zipped folder:
The zip folder produced was 14.7MB. Windows can open a zipped folder like any other folder so you can still easily read the pdf in its original form.

Reduced resolution and increased compression with Libre Office:
Opened in Libre Office Writer and exported to pdf, image resolution reduced from 300dpi to 150dpi, jpeg compression quality lowered to 33%. The exported pdf was 5.32MB. The loss of image quality was unnoticeable but some formatting changes were introduced, particularly in the alignment of the table of chapters. Such problems may be found in other pdf compression software, so beware.

 

PDF file size

When I make PDFs using my Canon MG6150 PIXMA and Acrobat XI, the resultant files are huge e.g. 15Mb. How can I set the file size or compress the file size so I can transmit the PDFs without incurring problems with email servers?

Thanks