I want to analyze and modify a stream data in a PDF file in c# programming. So, maybe the first step is to decode stream data and then modify stream data for PDF page. I really need help on this issue and can't seem to find anything online that works....please can someone offer me some advice and support??

This product on XsPDF.com might be what you looking for, check out: XsPDF .NET PDF Basic Library SDK.

Answers

By considering decoding stream data of a PDF page, there are a number of tools on Google.com search result. Why not search for one that help you walk the object tree and see what inside compressed streams easily.

I can decode the stream data now but i meet a new problem which the text is hex encoded like <0044>Tj. And i cannot figure out what is it because it does not match the standard ASCII or any Unicode value. Please help me out.

To figure out which character is it you need to use the ToUnicodeMap which maps glyph IDs to Unicode characters. Generally, the values of glyph IDs and Unicode characters are different. So, from my point of view, you would better to embed the whole font and set the glyph IDs and Unicode values match with an offset partially. By doing this, you can easily encode or decode the text and do more further analysis or modifications.