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/*
* 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 javax.imageio.plugins.jpeg;
import org.apache.harmony.x.imageio.plugins.jpeg.JPEGConsts;
import javax.imageio.ImageWriteParam;
import java.util.Locale;
/**
* The JPEGImageWriteParam class allows to set JPEG Huffman tables and
* quantization when using the JPEG writer plug-in.
*
* @since Android 1.0
*/
public class JPEGImageWriteParam extends ImageWriteParam {
/**
* The Constant COMP_QUALITY_VALUES.
*/
private static final float[] COMP_QUALITY_VALUES = {
0.05f, 0.75f, 0.95f
};
/**
* The Constant COMP_QUALITY_DESCRIPTIONS.
*/
private static final String[] COMP_QUALITY_DESCRIPTIONS = {
"Minimum useful", "Visually lossless", "Maximum useful"
};
/**
* The q tables.
*/
private JPEGQTable[] qTables;
/**
* The dc huffman tables.
*/
private JPEGHuffmanTable[] dcHuffmanTables;
/**
* The ac huffman tables.
*/
private JPEGHuffmanTable[] acHuffmanTables;
/**
* The optimize huffman tables.
*/
private boolean optimizeHuffmanTables;
/**
* Instantiates a new JPEGImageWriteParam object with the specified Locale.
*
* @param locale
* the Locale.
*/
public JPEGImageWriteParam(Locale locale) {
super(locale);
canWriteProgressive = true;
progressiveMode = ImageWriteParam.MODE_DISABLED;
canWriteCompressed = true;
compressionTypes = new String[] {
"JPEG"
};
compressionType = compressionTypes[0];
compressionQuality = JPEGConsts.DEFAULT_JPEG_COMPRESSION_QUALITY;
}
/**
* Returns true if tables are set, false otherwise.
*
* @return true, if tables are set, false otherwise.
*/
public boolean areTablesSet() {
return qTables != null;
}
/**
* Sets the quantization and Huffman tables for using in encoding streams.
*
* @param qTables
* the quantization tables.
* @param DCHuffmanTables
* the standart DC Huffman tables.
* @param ACHuffmanTables
* the standart AC huffman tables.
*/
public void setEncodeTables(JPEGQTable[] qTables, JPEGHuffmanTable[] DCHuffmanTables,
JPEGHuffmanTable[] ACHuffmanTables) {
if (qTables == null || DCHuffmanTables == null || ACHuffmanTables == null) {
throw new IllegalArgumentException("Invalid JPEG table arrays");
}
if (DCHuffmanTables.length != ACHuffmanTables.length) {
throw new IllegalArgumentException("Invalid JPEG table arrays");
}
if (qTables.length > 4 || DCHuffmanTables.length > 4) {
throw new IllegalArgumentException("Invalid JPEG table arrays");
}
// Do the shallow copy, it should be enough
this.qTables = qTables.clone();
dcHuffmanTables = DCHuffmanTables.clone();
acHuffmanTables = ACHuffmanTables.clone();
}
/**
* Unset all encoded tables.
*/
public void unsetEncodeTables() {
qTables = null;
dcHuffmanTables = null;
acHuffmanTables = null;
}
/**
* Gets the DC Huffman tables.
*
* @return the DC Huffman tables which are set, or null.
*/
public JPEGHuffmanTable[] getDCHuffmanTables() {
return dcHuffmanTables == null ? null : dcHuffmanTables.clone();
}
/**
* Gets the AC Huffman tables.
*
* @return the AC Huffman tables which are set, or null.
*/
public JPEGHuffmanTable[] getACHuffmanTables() {
return acHuffmanTables == null ? null : acHuffmanTables.clone();
}
/**
* Gets the quantization tables.
*
* @return the quantization tables, or null.
*/
public JPEGQTable[] getQTables() {
return qTables == null ? null : qTables.clone();
}
@Override
public String[] getCompressionQualityDescriptions() {
super.getCompressionQualityDescriptions();
return COMP_QUALITY_DESCRIPTIONS.clone();
}
@Override
public float[] getCompressionQualityValues() {
super.getCompressionQualityValues();
return COMP_QUALITY_VALUES.clone();
}
/**
* Sets the flag indicated that the writer will generate optimized Huffman
* tables for the image as part of the writing process.
*
* @param optimize
* the flag of optimizing huffman tables.
*/
public void setOptimizeHuffmanTables(boolean optimize) {
optimizeHuffmanTables = optimize;
}
/**
* Returns true if the writer generates optimized Huffman tables, false
* otherwise.
*
* @return true, if the writer generates optimized Huffman tables, false
* otherwise.
*/
public boolean getOptimizeHuffmanTables() {
return optimizeHuffmanTables;
}
@Override
public boolean isCompressionLossless() {
if (getCompressionMode() != MODE_EXPLICIT) {
throw new IllegalStateException("Compression mode not MODE_EXPLICIT!");
}
return false;
}
@Override
public void unsetCompression() {
if (getCompressionMode() != MODE_EXPLICIT) {
throw new IllegalStateException("Compression mode not MODE_EXPLICIT!");
}
compressionQuality = JPEGConsts.DEFAULT_JPEG_COMPRESSION_QUALITY;
}
}
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