Most of the time, you can just use a PDF file without thinking about what lies ‘under the bonnet’. But sometimes you want to find out about the actual objects inside a PDF file.
I need to do this quite often to debug our PDF viewer but it is also useful if you want to know about the colors used and how the PDF might print or whether it has any useful text. It also allows you to see how big the images inside the PDF really are and whether they can be easily extracted.
I used to open the PDF in a text editor but this is not an ideal solution. Not only can it be quite hard to decipher, but if the PDF is encrypted or contains compressed data and objects you cannot view these.
So I was really pleased to find a little feature hidden inside the Advanced menu option of Acrobat 9.0 to ‘Browse Internal PDF Structure‘
This allows you to see the actual PDF objects much more clearly. You will still need your trusty and well-thumbed copy of the Adobe Acrobat PDF specification but it has saved me a lot of time when needing to see what is happening inside a PDF file.
This post is part of our “Understanding the PDF File Format” series. In each article, we aim to take a specific PDF feature and explain it in simple terms. If you wish to learn more about PDF, we have 13 years worth of PDF knowledge and tips, so click here to visit our series index!
Want to try a Java PDF Library? Try JPedal for free, download the free trial Jar.
Latest posts by Mark Stephens (see all)
- Major JPedal Java PDF Library SDK update in April - April 19, 2016
- Announcing the schedule for the second free NetBeans UK Day (at Greenwich University) on 31st May - April 11, 2016
- A timely lesson on why it is a bad idea to edit a PDF file directly - March 22, 2016
- Tickets now available for free UK NetBeans Day - March 17, 2016
- How does your team celebrate a successful win? - March 17, 2016