/*
* Copyright (C)2011, 2013-2015 D. R. Commander. All Rights Reserved.
* Copyright (C)2015 Viktor Szathmáry. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the libjpeg-turbo Project nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS",
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package org.libjpegturbo.turbojpeg;
/**
* TurboJPEG lossless transformer
*/
public class TJTransformer extends TJDecompressor {
/**
* Create a TurboJPEG lossless transformer instance.
*/
public TJTransformer() throws TJException {
init();
}
/**
* Create a TurboJPEG lossless transformer instance and associate the JPEG
* image stored in <code>jpegImage</code> with the newly created instance.
*
* @param jpegImage JPEG image buffer (size of the JPEG image is assumed to
* be the length of the array.) This buffer is not modified.
*/
public TJTransformer(byte[] jpegImage) throws TJException {
init();
setSourceImage(jpegImage, jpegImage.length);
}
/**
* Create a TurboJPEG lossless transformer instance and associate the JPEG
* image of length <code>imageSize</code> bytes stored in
* <code>jpegImage</code> with the newly created instance.
*
* @param jpegImage JPEG image buffer. This buffer is not modified.
*
* @param imageSize size of the JPEG image (in bytes)
*/
public TJTransformer(byte[] jpegImage, int imageSize) throws TJException {
init();
setSourceImage(jpegImage, imageSize);
}
/**
* Losslessly transform the JPEG image associated with this transformer
* instance into one or more JPEG images stored in the given destination
* buffers. Lossless transforms work by moving the raw coefficients from one
* JPEG image structure to another without altering the values of the
* coefficients. While this is typically faster than decompressing the
* image, transforming it, and re-compressing it, lossless transforms are not
* free. Each lossless transform requires reading and performing Huffman
* decoding on all of the coefficients in the source image, regardless of the
* size of the destination image. Thus, this method provides a means of
* generating multiple transformed images from the same source or of applying
* multiple transformations simultaneously, in order to eliminate the need to
* read the source coefficients multiple times.
*
* @param dstBufs an array of image buffers. <code>dstbufs[i]</code> will
* receive a JPEG image that has been transformed using the parameters in
* <code>transforms[i]</code>. Use {@link TJ#bufSize} to determine the
* maximum size for each buffer based on the transformed or cropped width and
* height and the level of subsampling used in the source image.
*
* @param transforms an array of {@link TJTransform} instances, each of
* which specifies the transform parameters and/or cropping region for the
* corresponding transformed output image
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*/
public void transform(byte[][] dstBufs, TJTransform[] transforms,
int flags) throws TJException {
if (jpegBuf == null)
throw new IllegalStateException("JPEG buffer not initialized");
transformedSizes = transform(jpegBuf, jpegBufSize, dstBufs, transforms,
flags);
}
/**
* Losslessly transform the JPEG image associated with this transformer
* instance and return an array of {@link TJDecompressor} instances, each of
* which has a transformed JPEG image associated with it.
*
* @param transforms an array of {@link TJTransform} instances, each of
* which specifies the transform parameters and/or cropping region for the
* corresponding transformed output image
*
* @return an array of {@link TJDecompressor} instances, each of
* which has a transformed JPEG image associated with it.
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*/
public TJDecompressor[] transform(TJTransform[] transforms, int flags)
throws TJException {
byte[][] dstBufs = new byte[transforms.length][];
if (jpegWidth < 1 || jpegHeight < 1)
throw new IllegalStateException("JPEG buffer not initialized");
for (int i = 0; i < transforms.length; i++) {
int w = jpegWidth, h = jpegHeight;
if ((transforms[i].options & TJTransform.OPT_CROP) != 0) {
if (transforms[i].width != 0) w = transforms[i].width;
if (transforms[i].height != 0) h = transforms[i].height;
}
dstBufs[i] = new byte[TJ.bufSize(w, h, jpegSubsamp)];
}
TJDecompressor[] tjd = new TJDecompressor[transforms.length];
transform(dstBufs, transforms, flags);
for (int i = 0; i < transforms.length; i++)
tjd[i] = new TJDecompressor(dstBufs[i], transformedSizes[i]);
return tjd;
}
/**
* Returns an array containing the sizes of the transformed JPEG images
* generated by the most recent transform operation.
*
* @return an array containing the sizes of the transformed JPEG images
* generated by the most recent transform operation.
*/
public int[] getTransformedSizes() {
if (transformedSizes == null)
throw new IllegalStateException("No image has been transformed yet");
return transformedSizes;
}
private native void init() throws TJException;
private native int[] transform(byte[] srcBuf, int srcSize, byte[][] dstBufs,
TJTransform[] transforms, int flags) throws TJException;
static {
TJLoader.load();
}
private int[] transformedSizes = null;
}