PDF types

Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic

   Hello, my PDF background is simply a user, in that I have Reader X to view pdf files, mostly books.

From what I can tell, there are 2 types that I run across, first a real text file, that I can copy/paste from and/or "save as" text, the second is an image file that you can't copy/paste or "save as" text.

I seem to have run across a third type that is an image that I can copy/paste from (haven't tried to "save as" yet as it is a large file)

Can someone fill me in on these different types ??

Thanks

Author	Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic
cowboy Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 12 Oct 2011 Points: 13	Post Options Post Reply Quote cowboy Report Post Quote Reply Topic: PDF types Posted: 12 Mar 2012 at 1:06pm
	Hello, my PDF background is simply a user, in that I have Reader X to view pdf files, mostly books. From what I can tell, there are 2 types that I run across, first a real text file, that I can copy/paste from and/or "save as" text, the second is an image file that you can't copy/paste or "save as" text. I seem to have run across a third type that is an image that I can copy/paste from (haven't tried to "save as" yet as it is a large file) Can someone fill me in on these different types ?? Thanks

Sponsored Links

aandi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 07 Jul 2011 Points: 17968	Post Options Post Reply Quote aandi Report Post Quote Reply Posted: 12 Mar 2012 at 1:44pm
	They aren't really different types of PDF. Every PDF can have some text, or none. And some pictures or none. Sometimes what looks like text is just a picture. Sometimes a picture has invisible text behind it, so that you can still copy/paste. A PDF can have any or all of these in any mixture.

aandi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 07 Jul 2011 Points: 17968	Post Options Post Reply Quote aandi Report Post Quote Reply Posted: 12 Mar 2012 at 1:57pm
	Perhaps I can answer a different question: "how can I tell if copy/paste will work for a particular PDF". Sadly, you can't. You can just try it and see.

Rowan Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Moderator Group Joined: 29 Jun 2011 Points: 79	Post Options Post Reply Quote Rowan Report Post Quote Reply Posted: 12 Mar 2012 at 1:58pm
	Anecdotally speaking, I've seen people refer to PDFs that have been generated from a scanned paper document (without subsequent OCR'ing) as image-based PDFs and PDFs generated from Microsoft Word (or similar authoring tools) as text-based PDFs. I guess they are called image-based PDFs because although they look like they might have selectable text, they actually do not. As aandi has already said, these aren't different types of PDFs -- just a simple (perhaps too simple to the point of being misleading) of describing the state of the text that you can see in a PDF.

cowboy Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 12 Oct 2011 Points: 13	Post Options Post Reply Quote cowboy Report Post Quote Reply Posted: 12 Mar 2012 at 2:28pm
	I understand everything that has been said here, except for the one about and image haveing text behind it... To clarify, I realize "pdf document" is a broad term. For my use and question, it is for those documents that appear to be text, like books. I get some frome Google books and other places. Clearly, especialy with Google, they are images, as when you try to copy/paste it won't work. Others, are just the opossite in that they will copy/paste.... It was the 3rd type that threw me, while it would let me copy/paste, yet when I tried to save a portion via "cutepdf" it came out as an image. I guess the "text behind the image" explains that. p.s. the gist of my needs/problem is to have a way to save portions of a pdf text file. Some times I may want to save 20 pages of a file, and there doesn't seem to be a way to do that via Reader i.e.(save all or none) Are there tools where you can do that ? "cutepdf" was one I used. The second part is dealing with imaged text, what would be the best way to convert image to text?

Rowan Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Moderator Group Joined: 29 Jun 2011 Points: 79	Post Options Post Reply Quote Rowan Report Post Quote Reply Posted: 23 Mar 2012 at 7:40am
	I recently wrote a tips and tricks article for Planet PDF which describes how to use Google Docs to convert a scanned PDF to text, you can read it here: Convert scanned PDFs to text documents using Google Docs As far as free solutions go, this is probably as good as you will get at this stage. As for saving 20 pages of a PDF file, I presume you mean you want to extract 20 pages from a PDF? Just search for a free tools that does PDF splitting. Most PDF splitting tools will let you split by page range. This is technically the same as "extracting", it's just a different term.