[PDFBOX-975] Shape transparency not respected when exporting to image

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.6.0
• Labels: patch pdf pdfbox transparent
• Assignee: Andreas Lehmkühler
• Reporter: Jesse Eichar
• Created: 14/Mar/11 10:24
• Updated: 02/Jul/11 16:29
• Resolved: 21/Mar/11 18:11

Description

When a pdf file has a shape that is drawn with a transparency value the transparency values are not respected when exported to image.

I have attached a small patch that fixes this issue. The patch does not fully satisfy the PDF transparency model, for example only Alpha composition is used. But it covers the most common use-case of drawing shapes with a transparency value for fill and stroke.

I have also attached a maven project that demonstrates the issue. It had a pdf with a shape in it that is semi transparent. Running the application (execute the runexample.sh script) will load that pdf and export it as an image. During the export (the output is a file called pdfAsImage) the transparency is lost.

Compare the exported image and the original pdf to see the difference. PDF is in src/main/resources/...