Extract images in pdf without affecting the resolution?

Question

My problem is I am tasked to extract images from a 640-paged pdf file. Majority of which are charts and tables with texts. Doing a simple copy and paste makes the image lose its resolution and the texts becomes blurry and sometimes unreadable.

Do you know of a better way to extract images in a PDF file without affecting the resolution?

Thanks a lot!

Answer 1

The best way is to use Adobe Acrobat Pro (2010 or newer versions). Go to File -> Save As -> More Options -> Encapsulated PostScript and then click Save.

Answer 2

Extracting the original resolution images is one of the free features of the Solid Framework SDK so if you create your solution in C#, this is it: http://www.soliddocuments.com/features.htm?product=SolidFramework

The sample application that illustrates this feature is also free if you need a GUI batch solution: http://www.pdf-internals.com/download.htm?product=SolidPDFMechanic

(I'm with Solid Documents)

Answer 3

From the XPDF suite (which is Free & Open Source Software) you can use pdfimages.exe CLI tool to extract all images from a PDF, or just all images from a range of pages. Here an example to extract all images from pages 33-36:

pdfimages.exe ^
  -f 33 ^
  -l 36 ^
  -j ^
   c:/path/to/input.pdf ^
   c:/path/to/directory/input_images

The -j will try to extract embedded JPEG images as JPEGs. All other images are output as PPMs (portable pixmaps). Attention, PPMs are totally uncompressed!

Answer 4

You could use Imagemagick to convert all PDF pages to separate image files (although I am not sure how long it will take to do such a big document, or if it will cope!) and then crop out what you want. Might be worth doing a trial run with this as at least you will find out whether the resolution of the embedded images is OK for what you need.

Answer 5

Which PDF viewing software are you using?

By using a PDF editing/creation program, like Adobe Acrobat Pro, you should be able to extract the embedded images as they are in the PDF file*. You can get a free trial from the Adobe site (for Windows and Mac), which you can use just for purpose.

* as long as they are not protected, in which case you will have to.. er, I'm not going there...

Answer 6

No - copying and pasting should retain the original resolution of the embedded resource - what is most likely happening is that it is a low resolution picture that was shrunk inside the PDF, so when it is exported, it looks worse than it is.

Try shrinking it and/or making it the same size as in the PDF and it should actually be the same.

Alternatively, (and worst option) go to 100% zoom and take a screenshot or use the snipping tool in Windows Vista / Windows 7.

NOTE - Images in .PDFs are usually shrunk/compressed at the time they are made converted to a .PDF, however, once it is has been compressed, you should be able to extract at the same quality as the PDF, not worse.