001/*
002 *  Licensed under the Apache License, Version 2.0 (the "License");
003 *  you may not use this file except in compliance with the License.
004 *  You may obtain a copy of the License at
005 *
006 *       http://www.apache.org/licenses/LICENSE-2.0
007 *
008 *  Unless required by applicable law or agreed to in writing, software
009 *  distributed under the License is distributed on an "AS IS" BASIS,
010 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
011 *  See the License for the specific language governing permissions and
012 *  limitations under the License.
013 *  under the License.
014 */
015
016package org.apache.commons.imaging.formats.png;
017
018import java.util.Collections;
019import java.util.List;
020
021import org.apache.commons.imaging.common.XmpImagingParameters;
022
023/**
024 * PNG format parameters.
025 *
026 * @since 1.0-alpha3
027 */
028public class PngImagingParameters extends XmpImagingParameters<PngImagingParameters> {
029
030    public static final byte DEFAULT_BIT_DEPTH = 8;
031
032    /**
033     * Bit depth. Default value is {@literal 8}.
034     */
035    private byte bitDepth = DEFAULT_BIT_DEPTH;
036
037    private boolean forceIndexedColor;
038
039    private boolean forceTrueColor;
040
041    private boolean predictorEnabled;
042
043    /**
044     * Used in write operations to indicate the Physical Scale - sCAL.
045     *
046     * <p>
047     * Valid values: PhysicalScale
048     * </p>
049     *
050     * @see org.apache.commons.imaging.formats.png.PhysicalScale
051     */
052    private PhysicalScale physicalScale;
053
054    /**
055     * <p>
056     * Only used when writing PNG images.
057     * </p>
058     *
059     * <p>
060     * Valid values: a list of WriteTexts.
061     * </p>
062     */
063    private List<? extends AbstractPngText> textChunks;
064
065    public byte getBitDepth() {
066        return bitDepth;
067    }
068
069    public PhysicalScale getPhysicalScale() {
070        return physicalScale;
071    }
072
073    public List<? extends AbstractPngText> getTextChunks() {
074        return textChunks != null ? Collections.unmodifiableList(textChunks) : null;
075    }
076
077    public boolean isForceIndexedColor() {
078        return forceIndexedColor;
079    }
080
081    public boolean isForceTrueColor() {
082        return forceTrueColor;
083    }
084
085    /**
086     * Indicates that the PNG write operation should enable the predictor.
087     *
088     * @return true if the predictor is enabled; otherwise, false.
089     */
090    public boolean isPredictorEnabled() {
091        return predictorEnabled;
092    }
093
094    public PngImagingParameters setBitDepth(final byte bitDepth) {
095        this.bitDepth = bitDepth;
096        return asThis();
097    }
098
099    public PngImagingParameters setForceIndexedColor(final boolean forceIndexedColor) {
100        this.forceIndexedColor = forceIndexedColor;
101        return asThis();
102    }
103
104    public PngImagingParameters setForceTrueColor(final boolean forceTrueColor) {
105        this.forceTrueColor = forceTrueColor;
106        return asThis();
107    }
108
109    public PngImagingParameters setPhysicalScale(final PhysicalScale physicalScale) {
110        this.physicalScale = physicalScale;
111        return asThis();
112    }
113
114    /**
115     * Sets the enabled status of the predictor. When performing data compression on an image, a PNG predictor often results in a reduced file size. Predictors
116     * are particularly effective on photographic images, but may also work on graphics. The specification of a predictor may result in an increased processing
117     * time when writing an image, but will not affect the time required to read an image.
118     *
119     * @param predictorEnabled true if a predictor is enabled; otherwise, false.
120     * @return {@code this} instance.
121     */
122    public PngImagingParameters setPredictorEnabled(final boolean predictorEnabled) {
123        this.predictorEnabled = predictorEnabled;
124        return asThis();
125    }
126
127    public PngImagingParameters setTextChunks(final List<? extends AbstractPngText> textChunks) {
128        this.textChunks = Collections.unmodifiableList(textChunks);
129        return asThis();
130    }
131}