In Picutre.resize() -> Picture.getPreferredSize() -> ImageUtils.getImageDimension() the image is read once again. Requesting enhancement to pass in Dimensions of the image before hand to avoid a slow read operation only to get dimensions. More Info on use case: http://stackoverflow.com/questions/34150804/apache-poi-xssfpicture-resize-too-slow-for-multiple-images-in-a-xssfsheet
Any chance you could produce a patch for this together with some unit-tests to cover the new functionality?