/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*/
package org.apache.shindig.gadgets.rewrite.image;
import org.apache.commons.io.IOUtils;
import org.apache.sanselan.ImageReadException;
import org.apache.sanselan.Sanselan;
import org.apache.shindig.gadgets.http.HttpResponse;
import javax.imageio.ImageIO;
import java.awt.color.ICC_Profile;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
/**
* Optimize JPEG images by either converting them to PNGs or re-encoding them with a more
* appropriate compression level.
*/
public class JPEGOptimizer extends BaseOptimizer {
public static BufferedImage readJpeg(InputStream is)
throws ImageReadException, IOException {
byte[] bytes = IOUtils.toByteArray(is);
// We cant use Sanselan to read JPEG but we can use it to read all the metadata which is
// where most security issues reside anyway in ImageIO
Sanselan.getMetadata(bytes, null);
byte[] iccBytes = Sanselan.getICCProfileBytes(bytes);
if (iccBytes != null && iccBytes.length > 0) {
ICC_Profile iccProfile = Sanselan.getICCProfile(bytes, null);
if (iccProfile == null) {
throw new ImageReadException("Image has ICC but it is corrupt and cannot be read");
}
}
return ImageIO.read(new ByteArrayInputStream(bytes));
}
private boolean usePng;
public JPEGOptimizer(OptimizerConfig config, HttpResponse original) {
super(config, original);
}
@Override
protected void rewriteImpl(BufferedImage image) throws IOException {
// Create a new optimizer config and disable JPEG conversion
OptimizerConfig pngConfig = new OptimizerConfig(config.getMaxInMemoryBytes(),
config.getMaxPaletteSize(), false, config.getJpegCompression(),
config.getMinThresholdBytes());
// Output the image as PNG
PNGOptimizer pngOptimizer = new PNGOptimizer(pngConfig, originalResponse);
pngOptimizer.rewriteImpl(image);
int pngLength = Integer.MAX_VALUE;
if (pngOptimizer.getRewrittenImage() != null) {
// PNG was better than original so use it
minBytes = pngOptimizer.getRewrittenImage();
minLength = minBytes.length;
pngLength = minLength;
}
// Write as standard JPEG using the configured default compression level
write(image);
// JPEG did not beat PNG
if (pngLength == minLength) {
usePng = true;
}
}
@Override
protected String getOutputContentType() {
if (usePng) {
return "image/png";
}
return "image/jpeg";
}
@Override
protected String getOriginalContentType() {
return "image/jpeg";
}
@Override
protected String getOriginalFormatName() {
return "jpeg";
}
}