/*
* #%L
* ACS AEM Commons Bundle
* %%
* Copyright (C) 2013 Adobe
* %%
* Licensed 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.
* #L%
*/
package com.adobe.acs.commons.images.transformers.impl;
import java.awt.Color;
import java.awt.Dimension;
import java.util.Map;
import org.apache.felix.scr.annotations.Activate;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Properties;
import org.apache.felix.scr.annotations.Property;
import org.apache.felix.scr.annotations.Service;
import org.apache.sling.api.resource.ValueMap;
import org.apache.sling.commons.osgi.PropertiesUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.adobe.acs.commons.images.ImageTransformer;
import com.day.image.Layer;
/**
* ACS AEM Commons - Image Transformer - Letter/Pillar Box ImageTransformer that
* resizes the layer. Accepts two Integer params: height and width. If either is
* left blank the missing dimension will be computed based on the original
* layer's aspect ratio. If the newly resized image does not fit into the
* original dimensions, this will create a background layer
*/
//@formatter:off
@Component
@Properties({
@Property(
name = ImageTransformer.PROP_TYPE,
value = LetterPillarBoxImageTransformerImpl.TYPE
)
})
@Service
//@formatter:on
public class LetterPillarBoxImageTransformerImpl implements ImageTransformer {
private static final Logger log = LoggerFactory.getLogger(LetterPillarBoxImageTransformerImpl.class);
static final String TYPE = "letter-pillar-box";
private static final String KEY_WIDTH = "width";
private static final String KEY_WIDTH_ALIAS = "w";
private static final String KEY_HEIGHT = "height";
private static final String KEY_HEIGHT_ALIAS = "h";
private static final String KEY_ALPHA = "alpha";
private static final String KEY_ALPHA_ALIAS = "a";
private static final String KEY_COLOR = "color";
private static final String KEY_COLOR_ALIAS = "c";
private static final Color TRANSPARENT = new Color(255, 255, 255, 0);
private static final int MAX_ALPHA = 255;
private static final int DEFAULT_MAX_DIMENSION = 50000;
private int maxDimension = DEFAULT_MAX_DIMENSION;
@Property(label = "Max dimension in px",
description = "Maximum size height and width can be re-sized to. [ Default: 50000 ]",
intValue = DEFAULT_MAX_DIMENSION)
public static final String PROP_MAX_DIMENSION = "max-dimension";
@Override
public final Layer transform(final Layer layer, final ValueMap properties) {
if ((properties == null) || properties.isEmpty()) {
log.warn("Transform [ {} ] requires parameters.", TYPE);
return layer;
}
log.debug("Transforming with [ {} ]", TYPE);
Dimension newSize = getResizeDimensions(properties, layer);
Color color = getColor(properties);
Layer resized = resize(layer, newSize);
Layer result = build(newSize, resized, color);
return result;
}
/*
* Creates the actual pillar/letter boxing.
*/
private Layer build(Dimension size, Layer img, Color color) {
Layer merged = new Layer(size.width, size.height, color);
int startXpos = 0;
int startYpos = 0;
int imgHeight = img.getHeight();
int imgWidth = img.getWidth();
if (imgHeight == size.height) {
// Pillar
startXpos = calculateStartPosition(size.width, imgWidth);
} else if (imgWidth == size.width) {
// Letter
startYpos = calculateStartPosition(size.height, imgHeight);
}
merged.blit(img, startXpos, startYpos, imgWidth, imgHeight, 0, 0);
return merged;
}
/*
* Resizes the layer but keeps original aspect ratio. Thus preparing it for
* the boxing.
*/
private Layer resize(Layer original, Dimension newDimensions) {
final Dimension origDimensions = new Dimension(original.getWidth(), original.getHeight());
final int fixedDimension = getFixedDimension(origDimensions, newDimensions);
float newWidth = newDimensions.width;
float newHeight = newDimensions.height;
if (fixedDimension < 0) {
// Height is "fixed", calculate width
newWidth = (origDimensions.width * newDimensions.height) / (float) origDimensions.height;
} else if (fixedDimension > 0) {
// Width is "fixed", calculate height
newHeight = (newDimensions.width * origDimensions.height) / (float) origDimensions.width;
}
original.resize(Math.round(newWidth), Math.round(newHeight));
return original;
}
/*
* Calculates whether width or height is being used for resize basis.
*
* Returns an indicator value on which dimension is the "fixed" dimension
*
* Zero if the aspect ratios are the same Negative if the width should be
* fixed Positive if the height should be fixed
*
* @param start the dimensions of the original image
*
* @param end the dimensions of the final image
*
* @return a value indicating which dimension is fixed
*/
private int getFixedDimension(Dimension start, Dimension end) {
double startRatio = start.getWidth() / start.getHeight();
double finalRatio = end.getWidth() / end.getHeight();
return Double.compare(startRatio, finalRatio);
}
private Dimension getResizeDimensions(final ValueMap properties, final Layer layer) {
int targetWidth = properties.get(KEY_WIDTH, properties.get(KEY_WIDTH_ALIAS, 0));
int targetHeight = properties.get(KEY_HEIGHT, properties.get(KEY_HEIGHT_ALIAS, 0));
int startWidth = layer.getWidth();
int startHeight = layer.getHeight();
if (targetWidth > maxDimension) {
targetWidth = maxDimension;
}
if (targetHeight > maxDimension) {
targetHeight = maxDimension;
}
if ((targetWidth < 1) && (targetHeight < 1)) {
targetWidth = startWidth;
targetHeight = startHeight;
} else if (targetWidth < 1) {
final float aspect = (float) targetHeight / startHeight;
targetWidth = Math.round(startWidth * aspect);
} else if (targetHeight < 1) {
final float aspect = (float) targetWidth / startWidth;
targetHeight = Math.round(startHeight * aspect);
}
return new Dimension(targetWidth, targetHeight);
}
private Color getColor(final ValueMap properties) {
String hexcolor = properties.get(KEY_COLOR, properties.get(KEY_COLOR_ALIAS, String.class));
int alpha = normalizeAlpha(properties.get(KEY_ALPHA, properties.get(KEY_ALPHA_ALIAS, 0.0)).floatValue());
Color color = TRANSPARENT;
if (hexcolor != null) {
try {
Color parsed = Color.decode("0x" + hexcolor);
color = new Color(parsed.getRed(), parsed.getGreen(), parsed.getBlue(), alpha);
} catch (NumberFormatException ex) {
log.warn("Invalid hex color specified: {}", hexcolor);
color = TRANSPARENT;
}
}
return color;
}
private int normalizeAlpha(float alpha) {
if (alpha > 1) {
alpha = 1f;
} else if (alpha < 0) {
alpha = 0f;
}
return Math.round(alpha * MAX_ALPHA);
}
private int calculateStartPosition(int originalSize, int newSize) {
int diff = originalSize - newSize;
int start = diff / 2;
return start;
}
@Activate
protected final void activate(final Map<String, String> config) {
maxDimension = PropertiesUtil.toInteger(config.get(PROP_MAX_DIMENSION), DEFAULT_MAX_DIMENSION);
}
}