Thanks for the suggestion desemondo!
I've been leaning very heavily on the Adobe document you referred to (especially the section you referenced) and I had actually seen that example too. Unfortunately it doesn't really help with my problem because my issue is PDF::API2-specific.
I guess it might be helpful to rephrase my question:
how do I use PDF::API2 to "import" the fonts that are embedded in a PDF so that I can map the character IDs used in the content stream to unicode code points (which can then be assembled into words and sentences...etc.)?
To put the question in perspective, here is a simple example of what I'm dealing with. In the example you supplied, the characters "ABC" are in a known encoding. They would be encoded in the PDF exactly as the example states. However I am dealing with PDFs that do something like:
BT
/F13 12 Tf
288 720 Td
[<01>4<02>-1<03>-1<04>-1<05>2<06>] TJ
ET
I need a way to use PDF::API2 to map the character IDs (the things between the angle brackets) to unicode code points...