Link to image within pdf, and have the image displayed?

Question

Is this possible? Basically, I have a file foo.png. I want to have foo.png displayed at a certain location in the pdf, while maintaining foo as a separate file. So, for example, if I changed the contents of the png file, the pdf would automatically display the new version, even if I didn't edit the pdf.

Answer 1

Maybe this is helpfull:

https://stackoverflow.com/questions/1833222/adding-external-images-to-pdf-using-itext

And here it might be described as possible:

http://en.wikipedia.org/wiki/Portable_Document_Format#Raster_images

"Normally all image content in a PDF is embedded in the file. But PDF allows image data to be stored in external files by the use of external streams or Alternate Images. Standardized subsets of PDF, including PDF/A and PDF/X, prohibit these techniques."

Answer 2

This is not possible. One of the many reasons that PDFs are popular is that they are self contained (PDF stands for "Portable Document Format"). They hold their own fonts for example, (this leads to viruses regularly getting in this way) and all images, videos, and other graphics are embedded.

As such, if they are self contained, they cannot change their content based on something outside of themselves.

It is possible to insert a hyperlink into a PDF, but I gather this is not what you are after.

Answer 3

PDFs are 'portable documents', they are virtually nothing but themselves, there is no dependency on other files, everything is stored within the PDF itself, you can't change an image elsewhere and have it auto-update it on the PDF, once the image is inside the pdf, it's inside until it's removed. The closest thing you could achieve in a PDF would be a hyperlink, or an alternative, a web page.

Good Luck!