/**
* Convert image formats which are not supported by Word (eg EPS, PDF), into ones which are. This
* requires ImageMagick to be on your system's path; for EPS and PDF images, Ghostscript is also
* required.
*
* @param is
* @param os
* @param density PixelsPerInch
* @throws IOException
* @throws InterruptedException
*/
public static void convertToPNG(InputStream is, OutputStream os, int density)
throws IOException, InterruptedException {
/*
* See http://www.eichberger.de/2006/05/imagemagick-in-servlets.html
*
* "Calling 'convert - png:-' as an external command and feeding it the
* source image as standard input and reading the converted image
* (in this case png) as standard output"
*
*/
log.info("Start ImageMagick...");
Process p =
Runtime.getRuntime()
.exec("imconvert -density " + density + " -units PixelsPerInch - png:-");
// GraphicsMagick is a little quicker than ImageMagick,
// but v1.3.3 (of Dec 2008) still has the now fixed in GM bug
// whereby the right most ~10% of the resulting image is chopped off
// Process p = Runtime.getRuntime().exec("gm convert -density " + density + " -units
// PixelsPerInch - png:-");
/* On Windows, if this results in "Invalid Parameter",
* then either ImageMagick is not installed,
* or exec is finding the wrong convert
* program. See http://studio.imagemagick.org/pipermail/magick-users/2005-October/016464.html
* and http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=8324&start=0
*
* Rather than use full path, rename convert to imconvert (which Alfresco and others do)
*
*/
// initialize Gobblers
StreamGobbler inGobbler = new StreamGobbler(p.getInputStream(), os);
StreamGobbler errGobbler = new StreamGobbler(p.getErrorStream(), System.err);
// start them
inGobbler.start();
errGobbler.start();
// p.getOutputStream() is the _output stream_ of the subprocess, so
// this copies is into the standard input stream of the process
try {
copy2(is, new BufferedOutputStream(p.getOutputStream()));
p.getOutputStream().close();
log.debug("Image copied...");
} catch (IOException ioe) {
ioe.printStackTrace();
// debug
copy2(p.getErrorStream(), System.err);
}
if (p.waitFor() != 0) {
log.error("Error");
}
log.debug("End Process...");
}
