Jan. 12, 2015
9:08 a.m.
Olivier wrote:
In fact, the PNG is converted to JPEG image before to be included in the PDF file. But the conversion process doesn't support transparency and sets a black background.
Jpeg doesn't have transparency. For browsers there is a hack. http://jim.studt.net/jpeg-alpha/ http://stackoverflow.com/questions/14220221/how-to-insert-transparent-png-in... PDF supports transparency since PDF 1.4 To avoid trouble, only use images with the same color space and either a 1 bit mask or a clipping path. Composing images in different color spaces with an alpha channel seems to be difficult to get right. Stephan