/*
* DefineImage2.java
* Transform
*
* Copyright (c) 2001-2010 Flagstone Software Ltd. 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 Flagstone Software Ltd. 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 OWNER 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 com.flagstone.transform.image;
import java.io.IOException;
import java.util.Arrays;
import com.flagstone.transform.Constants;
import com.flagstone.transform.MovieTypes;
import com.flagstone.transform.coder.Coder;
import com.flagstone.transform.coder.Context;
import com.flagstone.transform.coder.SWFDecoder;
import com.flagstone.transform.coder.SWFEncoder;
import com.flagstone.transform.exception.IllegalArgumentRangeException;
/**
* DefineImage2 is used to define a transparent image compressed using the
* lossless zlib compression algorithm.
*
* <p>
* The class supports colour-mapped images where the image data contains an
* index into a colour table or direct-mapped images where the colour is
* specified directly. It extends DefineImage by including alpha channel
* information for the colour table and pixels in the image.
* </p>
*
* <p>
* For colour-mapped images the colour table contains up to 256, 32-bit colours.
* The image contains one byte for each pixel which is an index into the table
* to specify the colour for that pixel. The colour table and the image data are
* compressed as a single block, with the colour table placed before the image.
* </p>
*
* <p>
* For images where the colour is specified directly, the image data contains 32
* bit colour values.
* </p>
*
* <p>
* The image data is stored in zlib compressed form within the object. For
* colour-mapped images the compressed data contains the colour table followed
* by the image data.
* </p>
*
* @see DefineImage
*/
public final class DefineImage2 implements ImageTag {
/** Format string used in toString() method. */
private static final String FORMAT = "DefineImage2: { identifier=%d;"
+ " width=%d; height=%d; pixelSize=%d; tableSize=%d;"
+ " image=byte<%d> ...}";
/** Identifies an indexed image. */
private static final int IDX_FORMAT = 3;
/** Identifies a true-color image with 32-bit pixels. */
private static final int RGBA_FORMAT = 5;
/** Size of a pixel in an indexed image. */
private static final int IDX_SIZE = 8;
/** Size of a pixel in an RGBA image. */
private static final int RGBA_SIZE = 32;
/** Number of entries in the colour table of an indexed image. */
private static final int TABLE_SIZE = 256;
/** The unique identifier for this object. */
private int identifier;
/** The width of the image in pixels. */
private int width;
/** The height of the image in pixels. */
private int height;
/** The number of bits in a pixel. */
private int pixelSize;
/** The number of entries in the colour table. */
private int tableSize;
/** The compressed colour table and image data. */
private byte[] image;
/** The length of the object, minus the header, when it is encoded. */
private transient int length;
/**
* Creates and initialises an DefineImage2 object using values encoded
* in the Flash binary format.
*
* @param coder
* an SWFDecoder object that contains the encoded Flash data.
*
* @throws IOException
* if an error occurs while decoding the data.
*/
public DefineImage2(final SWFDecoder coder) throws IOException {
length = coder.readUnsignedShort() & Coder.LENGTH_FIELD;
if (length == Coder.IS_EXTENDED) {
length = coder.readInt();
}
coder.mark();
identifier = coder.readUnsignedShort();
if (coder.readByte() == IDX_FORMAT) {
pixelSize = IDX_SIZE;
} else {
pixelSize = RGBA_SIZE;
}
width = coder.readUnsignedShort();
height = coder.readUnsignedShort();
if (pixelSize == IDX_SIZE) {
tableSize = coder.readByte() + 1;
// CHECKSTYLE IGNORE MagicNumberCheck FOR NEXT 1 LINES
image = coder.readBytes(new byte[length - 8]);
} else {
// CHECKSTYLE IGNORE MagicNumberCheck FOR NEXT 1 LINES
image = coder.readBytes(new byte[length - 7]);
}
coder.check(length);
coder.unmark();
}
/**
* Creates a DefineImage2 object defining a colour-mapped image.
*
* @param uid
* the unique identifier for this object. Must be in the range
* 1..65535.
* @param imgWidth
* the width of the image. Must be in the range 0..65535.
* @param imgHeight
* the height of the image. Must be in the range 0..65535.
* @param size
* the number of entries in the colour table in the compressed
* data. Each entry is 32 bits. Must be in the range 1..256.
* @param data
* the zlib compressed colour table and image data. Must not be
* null.
*/
public DefineImage2(final int uid, final int imgWidth, final int imgHeight,
final int size, final byte[] data) {
setIdentifier(uid);
setWidth(imgWidth);
setHeight(imgHeight);
setPixelSize(IDX_SIZE);
setTableSize(size);
setImage(data);
}
/**
* Creates a DefineImage object defining a true-colour image. Each pixel in
* the image is 32 bits - 8 bits for the red, green, blue and alpha colour
* channels.
*
* @param uid
* the unique identifier for this object. Must be in the range
* 1..65535.
* @param imgWidth
* the width of the image. Must be in the range 0..65535.
* @param imgHeight
* the height of the image. Must be in the range 0..65535.
* @param data
* the zlib compressed image data. Must not be null.
*/
public DefineImage2(final int uid, final int imgWidth, final int imgHeight,
final byte[] data) {
setIdentifier(uid);
setWidth(imgWidth);
setHeight(imgHeight);
setPixelSize(RGBA_SIZE);
tableSize = 0;
setImage(data);
}
/**
* Creates and initialises a DefineImage2 object using the values copied
* from another DefineImage2 object.
*
* @param object
* a DefineImage2 object from which the values will be
* copied.
*/
public DefineImage2(final DefineImage2 object) {
identifier = object.identifier;
width = object.width;
height = object.height;
pixelSize = object.pixelSize;
tableSize = object.tableSize;
image = object.image;
}
/** {@inheritDoc} */
public int getIdentifier() {
return identifier;
}
/** {@inheritDoc} */
public void setIdentifier(final int uid) {
if ((uid < 1) || (uid > Coder.USHORT_MAX)) {
throw new IllegalArgumentRangeException(
1, Coder.USHORT_MAX, uid);
}
identifier = uid;
}
/**
* Get the width of the image in pixels (not twips).
*
* @return the width of the image.
*/
public int getWidth() {
return width;
}
/**
* Get the height of the image in pixels (not twips).
*
* @return the height of the image.
*/
public int getHeight() {
return height;
}
/**
* Get the number of bits used to represent each pixel. Either 8 or 32
* bits. The pixel size is 8-bits for colour-mapped images and 32 bits for
* images where the colour is specified directly.
*
* @return the number of bits for each pixel.
*/
public int getPixelSize() {
return pixelSize;
}
/**
* Get the number of entries in the colour table encoded the compressed
* image. For images where the colour is specified directly in the image
* then the table size is zero.
*
* @return the number of entries in the colour table.
*/
public int getTableSize() {
return tableSize;
}
/**
* Get a copy of the compressed colour table and image.
*
* @return a copy of the data.
*/
public byte[] getImage() {
return Arrays.copyOf(image, image.length);
}
/**
* Sets the width of the image in pixels.
*
* @param aNumber
* the width of the image. Must be in the range of 0..65535.
*/
public void setWidth(final int aNumber) {
if ((aNumber < 0) || (aNumber > Coder.USHORT_MAX)) {
throw new IllegalArgumentRangeException(
0, Coder.USHORT_MAX, aNumber);
}
width = aNumber;
}
/**
* Sets the height of the image in pixels.
*
* @param aNumber
* the height of the image. Must be in the range of 0..65535.
*/
public void setHeight(final int aNumber) {
if ((aNumber < 0) || (aNumber > Coder.USHORT_MAX)) {
throw new IllegalArgumentRangeException(
0, Coder.USHORT_MAX, aNumber);
}
height = aNumber;
}
/**
* Sets the size of the pixel in bits: 8 for colour-mapped images, 32 for
* direct images.
*
* @param size
* the size of each pixel in bits: must be either 8 or 32.
*/
public void setPixelSize(final int size) {
if ((size != IDX_SIZE) && (size != RGBA_SIZE)) {
throw new IllegalArgumentException(
"Pixel size must be either 8 or 32 bits.");
}
pixelSize = size;
}
/**
* Sets the number of entries in the colour table in the compressed image.
* For images where the colour is specified directly in the image then the
* table size should be zero.
*
* @param size
* the number of entries in the colour table in the compressed
* image. Must be in the range 1..256.
*/
public void setTableSize(final int size) {
if ((size < 1) || (size > TABLE_SIZE)) {
throw new IllegalArgumentException(
"Colour table size must be in the range 1..256.");
}
tableSize = size;
}
/**
* Sets the data containing the compressed image and colour table.
*
* @param bytes
* byte array containing zlib compressed colour table and image.
* Must not be null.
*/
public void setImage(final byte[] bytes) {
if (bytes == null) {
throw new IllegalArgumentException();
}
image = Arrays.copyOf(bytes, bytes.length);
}
/** {@inheritDoc} */
public DefineImage2 copy() {
return new DefineImage2(this);
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format(FORMAT, identifier, width, height, pixelSize,
tableSize, image.length);
}
/** {@inheritDoc} */
public int prepareToEncode(final Context context) {
// CHECKSTYLE IGNORE MagicNumberCheck FOR NEXT 1 LINES
length = 7;
length += (pixelSize == IDX_SIZE) ? 1 : 0;
length += image.length;
return Coder.LONG_HEADER + length;
}
/** {@inheritDoc} */
public void encode(final SWFEncoder coder, final Context context)
throws IOException {
coder.writeShort((MovieTypes.DEFINE_IMAGE_2 << Coder.LENGTH_FIELD_SIZE)
| Coder.IS_EXTENDED);
coder.writeInt(length);
if (Constants.DEBUG) {
coder.mark();
}
coder.writeShort(identifier);
if (pixelSize == IDX_SIZE) {
coder.writeByte(IDX_FORMAT);
} else { // 32
coder.writeByte(RGBA_FORMAT);
}
coder.writeShort(width);
coder.writeShort(height);
if (pixelSize == IDX_SIZE) {
coder.writeByte(tableSize - 1);
}
coder.writeBytes(image);
if (Constants.DEBUG) {
coder.check(length);
coder.unmark();
}
}
}