    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}