One of the powerful features of the PDF file specification is the support for transparency in the Canvas. When an image is drawn on the page, the image can have an alpha setting which defines how transparent the image is. The value is between 0 and 1 (where 0 is totally invisible and 1 has no transparency). Transparency is often used for special effects like adding a watermark – draw an image with a 0.2 transparency setting or less.
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IDRsolutions develop a Java PDF library, a PDF forms to HTML5 converter, a PDF to HTML5 or SVG converter and a Java Image Library that doubles as an ImageIO replacement. On the blog our team post about anything interesting they learn about.