/**
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @author Arne Kepp, The Open Planning Project, Copyright 2008
*
*/
package org.geowebcache.mime;
import java.awt.image.IndexColorModel;
import java.awt.image.RenderedImage;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.Iterator;
import javax.imageio.ImageWriter;
import javax.media.jai.JAI;
import javax.media.jai.RenderedOp;
import javax.media.jai.operator.ExtremaDescriptor;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class ImageMime extends MimeType {
public static final String NATIVE_PNG_WRITER_CLASS_NAME = "com.sun.media.imageioimpl.plugins.png.CLibPNGImageWriter";
private static Log log = LogFactory.getLog(org.geowebcache.mime.ImageMime.class);
boolean supportsAlphaChannel;
boolean supportsAlphaBit;
public static final ImageMime png =
new ImageMime("image/png", "png", "png", "image/png", true, true, true) {
/**
* Any response mime starting with image/png will do
*/
public boolean isCompatible(String otherMimeType) {
return super.isCompatible(otherMimeType) || otherMimeType.startsWith("image/png");
};
};
public static final ImageMime jpeg =
new ImageMime("image/jpeg", "jpeg", "jpeg", "image/jpeg", true, false, false);
public static final ImageMime gif =
new ImageMime("image/gif", "gif", "gif", "image/gif", true, false, true);
public static final ImageMime tiff =
new ImageMime("image/tiff", "tiff", "tiff", "image/tiff", true, true, true);
public static final ImageMime png8 =
new ImageMime("image/png", "png8", "png", "image/png8", true, false, true);
public static final ImageMime png24 =
new ImageMime("image/png", "png24", "png", "image/png24", true, true, true);
public static final ImageMime png_24 =
new ImageMime("image/png; mode=24bit", "png_24", "png", "image/png;%20mode=24bit", true, true, true);
public static final ImageMime dds =
new ImageMime("image/dds", "dds", "dds", "image/dds", false, false, false);
public static final ImageMime jpegPng =
new ImageMime("image/vnd.jpeg-png", "jpeg-png", "jpeg-png", "image/vnd.jpeg-png", true, true, true) {
private static final int JPEG_MAGIC_MASK = 0xffd80000;
/**
* Returns true if the best format to encode the image is jpeg (the image is rgb, or rgba without any actual
* transparency use). This code is duplicated in GeoServer JpegPngRenderedImageMapOutputFormat. Unfortunately
* gwc-core does not depend on GeoTools, so we don't have an easy place to share it. On the bright side, it's small.
*
* @param renderedImage
* @param renderingHints
* @return
*/
boolean isBestFormatJpeg(RenderedImage renderedImage)
{
int numBands = renderedImage.getSampleModel().getNumBands();
if (numBands == 4 || numBands == 2)
{
RenderedOp extremaOp = ExtremaDescriptor.create(renderedImage, null, 1, 1, false, 1, JAI.getDefaultInstance().getRenderingHints());
double[][] extrema = (double[][]) extremaOp.getProperty("Extrema");
double[] mins = extrema[0];
return mins[mins.length - 1] == 255; // fully opaque
} else if(renderedImage.getColorModel() instanceof IndexColorModel) {
// JPEG would still compress a bit better, but in order to figure out
// if the image has transparency we'd have to expand to RGB or roll
// a new JAI image op that looks for the transparent pixels. Out of scope for the moment
return false;
} else {
// otherwise support RGB or gray
return (numBands == 3) || (numBands == 1);
}
}
public ImageWriter getImageWriter(RenderedImage image) {
if(isBestFormatJpeg(image)) {
return jpeg.getImageWriter(image);
} else {
return png.getImageWriter(image);
}
}
public String getMimeType(org.geowebcache.io.Resource resource) throws IOException {
try(DataInputStream dis = new DataInputStream(resource.getInputStream()))
{
final int head = dis.readInt();
if((head & 0xFFFF0000) == JPEG_MAGIC_MASK) {
return jpeg.getMimeType();
} else {
return png.getMimeType();
}
}
};
@Override
public boolean isCompatible(String otherMimeType) {
return jpeg.isCompatible(otherMimeType) || png.isCompatible(otherMimeType);
}
};
private ImageMime(String mimeType, String fileExtension,
String internalName, String format, boolean tiled,
boolean alphaChannel, boolean alphaBit) {
super(mimeType, fileExtension, internalName, format, tiled);
this.supportsAlphaChannel = alphaChannel;
this.supportsAlphaBit = alphaBit;
}
protected static ImageMime checkForFormat(String formatStr) throws MimeException {
if (!formatStr.startsWith("image/")) {
return null;
}
final String tmpStr = formatStr.substring(6, formatStr.length());
// TODO Making a special exception, generalize later
if (!formatStr.equals("image/png; mode=24bit") && formatStr.contains(";")) {
if (log.isDebugEnabled()) {
log.debug("Slicing off " + formatStr.split(";")[1]);
}
formatStr = formatStr.split(";")[0];
}
if (tmpStr.equalsIgnoreCase("png")) {
return png;
} else if (tmpStr.equalsIgnoreCase("jpeg")) {
return jpeg;
} else if (tmpStr.equalsIgnoreCase("gif")) {
return gif;
} else if (tmpStr.equalsIgnoreCase("tiff")) {
return tiff;
} else if (tmpStr.equalsIgnoreCase("png8")) {
return png8;
} else if (tmpStr.equalsIgnoreCase("png24")) {
return png24;
} else if (tmpStr.equalsIgnoreCase("png; mode=24bit")) {
return png_24;
} else if (tmpStr.equalsIgnoreCase("png;%20mode=24bit")) {
return png_24;
} else if(tmpStr.equalsIgnoreCase("vnd.jpeg-png")) {
return jpegPng;
}
return null;
}
protected static ImageMime checkForExtension(String fileExtension)
throws MimeException {
if (fileExtension.equalsIgnoreCase("png")) {
return png;
} else if (fileExtension.equalsIgnoreCase("jpeg") || fileExtension.equalsIgnoreCase("jpg")) {
return jpeg;
} else if (fileExtension.equalsIgnoreCase("gif")) {
return gif;
} else if (fileExtension.equalsIgnoreCase("tiff")) {
return tiff;
} else if (fileExtension.equalsIgnoreCase("png8")) {
return png8;
} else if (fileExtension.equalsIgnoreCase("png24")) {
return png24;
} else if (fileExtension.equalsIgnoreCase("png_24")) {
return png_24;
} else if (fileExtension.equalsIgnoreCase("jpeg-png")) {
return jpegPng;
}
return null;
}
public boolean supportsAlphaBit() {
return supportsAlphaBit;
}
public boolean supportsAlphaChannel() {
return supportsAlphaChannel;
}
public ImageWriter getImageWriter(RenderedImage image) {
Iterator<ImageWriter> it = javax.imageio.ImageIO.getImageWritersByFormatName(internalName);
ImageWriter writer = it.next();
//Native PNG Writer can't handle 2-4 bit PNG, so if our sample depth isn't 1/8 and the
//returned writer is the native version, let's skip it and move on to the next
//which will presumably be the pure Java version. A bit hacky, but it's roughly what
//GeoServer does to make sure it doesn't encode incompatible PNGs with the native writer
if (this.internalName.equals(ImageMime.png.internalName)
|| this.internalName.equals(ImageMime.png8.internalName)) {
int bitDepth = image.getSampleModel().getSampleSize(0);
if (bitDepth > 1 && bitDepth < 8
&& writer.getClass().getName().equals(NATIVE_PNG_WRITER_CLASS_NAME)) {
writer = it.next();
}
}
return writer;
}
}