PNG Image Handling

iText Core 7.1.11 introduced more robust PNG image handling to address an issue which could occur when adding certain PNG images to a PDF.

Details

• When we use iText to add a PNG image to a document, in a few use cases we end up with a PDF file which Acrobat or other PDF viewers are unable to open.
• Certain PNG images with Indexed colorspace to a PDF document resulted in a corrupted PDF. The reason for this issue is that if during deserialization the attributes of the image's colorspace start with "/" (slash) character, then we should translate it to a PdfName object. However that is not true for some attributes. 
• Prior to iText 7.1.11, iText parsed it incorrectly into a PdfName object, resulting in a corrupted PDF.
• After fixing this problem , iText generates the PdfStream object with the correct image's info inside.

Below is an example demonstrating the new behavior:

##GITHUB:https://github.com/RagvendraSingh/releaseexample/blob/master/FixPNGIssue.java##

##GITHUB:https://github.com/RagvendraSingh/releaseexample/blob/master/FixPNGIssue.cs##