/*
* Copyright (c) 2014, Harald Kuhr
* 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 "TwelveMonkeys" 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.twelvemonkeys.imageio.plugins.sgi;
import javax.imageio.IIOException;
import javax.imageio.stream.ImageInputStream;
import java.io.IOException;
import java.nio.charset.Charset;
final class SGIHeader {
private int compression;
private int bytesPerPixel;
private int dimensions;
private int width;
private int height;
private int channels;
private int minValue;
private int maxValue;
private String name;
private int colorMode;
public int getCompression() {
return compression;
}
public int getBytesPerPixel() {
return bytesPerPixel;
}
public int getWidth() {
return width;
}
public int getHeight() {
return height;
}
public int getChannels() {
return channels;
}
public int getMinValue() {
return minValue;
}
public int getMaxValue() {
return maxValue;
}
public String getName() {
return name;
}
public int getColorMode() {
return colorMode;
}
@Override public String toString() {
return "SGIHeader{" +
"compression=" + compression +
", bytesPerPixel=" + bytesPerPixel +
", dimensions=" + dimensions +
", width=" + width +
", height=" + height +
", channels=" + channels +
", minValue=" + minValue +
", maxValue=" + maxValue +
", name='" + name + '\'' +
", colorMode=" + colorMode +
'}';
}
public static SGIHeader read(final ImageInputStream imageInput) throws IOException {
// typedef struct _SGIHeader
// {
// SHORT Magic; /* Identification number (474) */
// CHAR Storage; /* Compression flag */
// CHAR Bpc; /* Bytes per pixel */
// WORD Dimension; /* Number of image dimensions */
// WORD XSize; /* Width of image in pixels */
// WORD YSize; /* Height of image in pixels */
// WORD ZSize; /* Number of bit channels */
// LONG PixMin; /* Smallest pixel value */
// LONG PixMax; /* Largest pixel value */
// CHAR Dummy1[4]; /* Not used */
// CHAR ImageName[80]; /* Name of image */
// LONG ColorMap; /* Format of pixel data */
// CHAR Dummy2[404]; /* Not used */
// } SGIHEAD;
short magic = imageInput.readShort();
if (magic != SGI.MAGIC) {
throw new IIOException(String.format("Not an SGI image. Expected SGI magic %04x, read %04x", SGI.MAGIC, magic));
}
SGIHeader header = new SGIHeader();
header.compression = imageInput.readUnsignedByte();
header.bytesPerPixel = imageInput.readUnsignedByte();
header.dimensions = imageInput.readUnsignedShort();
header.width = imageInput.readUnsignedShort();
header.height = imageInput.readUnsignedShort();
header.channels = imageInput.readUnsignedShort();
header.minValue = imageInput.readInt();
header.maxValue = imageInput.readInt();
imageInput.readInt(); // Ignore
byte[] nameBytes = new byte[80];
imageInput.readFully(nameBytes);
header.name = toAsciiString(nameBytes);
header.colorMode = imageInput.readInt();
imageInput.skipBytes(404);
return header;
}
private static String toAsciiString(final byte[] bytes) {
// Find null-terminator
int len = bytes.length;
for (int i = 0; i < bytes.length; i++) {
if (bytes[i] == 0) {
len = i;
break;
}
}
return new String(bytes, 0, len, Charset.forName("ASCII"));
}
}