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diff --git a/src/jake2/imageio/WALImageReaderSpi.java b/src/jake2/imageio/WALImageReaderSpi.java
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+/*
+ * Created on Nov 18, 2003
+ *
+ */
+package jake2.imageio;
+
+import java.io.IOException;
+import java.util.Locale;
+import javax.imageio.ImageReader;
+import javax.imageio.spi.ImageReaderSpi;
+import javax.imageio.stream.ImageInputStream;
+
+/**
+ * @author cwei
+ * 
+ * Quake 2 stores textures in a proprietary 2D image format called WAL.
+ * While this isn't actually part of the BSP file format,
+ * it's essential information for loading Quake 2 maps.
+ * WAL textures are stored in a 8-bit indexed color format with a specific palette being used by all textures.
+ * (this palette is stored in the PAK data file that comes with Quake 2 e.g. pics/colormap.pcx).
+ * Four mip-map levels are stored for each texture at sizes decreasing by a factor of two.
+ * This is mostly for software rendering since most 3D APIs will automatically generate
+ * the mip-map levels when you create a texture.
+ * Each frame of an animated texture is stored as an individual WAL file,
+ * and the animation sequence is encoded by storing the name of the next texture in the sequence for each frame;
+ * texture names are stored with paths and without any extension.
+ * The format for the WAL file header is the wal_header structure:
+ * <code>
+	struct wal_header
+	{
+    	char    name[32];        // name of the texture
+ 
+    	uint32  width;           // width (in pixels) of the largest mipmap level
+    	uint32  height;          // height (in pixels) of the largest mipmap level
+ 
+    	int32   offset[4];       // byte offset of the start of each of the 4 mipmap levels
+
+    	char    next_name[32];   // name of the next texture in the animation
+
+    	uint32  flags;           // ?
+    	uint32  contents;        // ?
+    	uint32  value;           // ?
+	};
+	</code>
+ * The actual texture data is stored in an 8-bits-per-pixel raw format in a left-right, top-down order.
+ * <br>
+ * put the own ImageReaderSpi class name in the file (relative to classpath):
+ * <code>META-INF/services/javax.imageio.spi.ImageReaderSpi</code>
+ * 
+ *  */
+public class WALImageReaderSpi extends ImageReaderSpi {
+
+	static final String vendorName = "[email protected]";
+	static final String version = "1.0_beta";
+	static final String[] names = { "quake2 wal" };
+	static final String[] suffixes = { "wal" };
+	static final String[] MIMETypes = { "image/x-quake2-wal" };
+	static final String readerClassName = "jake2.imageio.WALImageReader";
+	static final String[] writerSpiNames = null; //		{ "jake2.imageio.WALImageWriterSpi" };
+
+	// Metadata formats, more information below
+	static final boolean supportsStandardStreamMetadataFormat = false;
+	static final String nativeStreamMetadataFormatName = null;
+
+	static final String nativeStreamMetadataFormatClassName = null;
+	static final String[] extraStreamMetadataFormatNames = null;
+	static final String[] extraStreamMetadataFormatClassNames = null;
+	static final boolean supportsStandardImageMetadataFormat = false;
+	static final String nativeImageMetadataFormatName =
+		"jake2.imageio.WALMetaData_1.0";
+	static final String nativeImageMetadataFormatClassName = null;	// "jake2.imageio.WALMetadata";
+	static final String[] extraImageMetadataFormatNames = null;
+	static final String[] extraImageMetadataFormatClassNames = null;
+
+	public WALImageReaderSpi() {
+
+		super(
+			vendorName,
+			version,
+			names,
+			suffixes,
+			MIMETypes,
+			readerClassName,
+			ImageReaderSpi.STANDARD_INPUT_TYPE, // Accept ImageInputStreams
+			writerSpiNames,
+			supportsStandardStreamMetadataFormat,
+			nativeStreamMetadataFormatName,
+			nativeStreamMetadataFormatClassName,
+			extraStreamMetadataFormatNames,
+			extraStreamMetadataFormatClassNames,
+			supportsStandardImageMetadataFormat,
+			nativeImageMetadataFormatName,
+			nativeImageMetadataFormatClassName,
+			extraImageMetadataFormatNames,
+			extraImageMetadataFormatClassNames);
+	}
+
+	public boolean canDecodeInput(Object source) throws IOException {
+		if (!(source instanceof ImageInputStream)) {
+			return false;
+		}
+		ImageInputStream stream = (ImageInputStream)source;
+		byte[] buffer = new byte[WAL.HEADER_SIZE];
+		try {
+			stream.mark();
+			stream.readFully(buffer);
+			stream.reset();
+			// buffer will be converted to members and header checked
+			WAL.Header wal = new WAL.Header(buffer); 
+		} catch (IllegalArgumentException e) {
+			return false;
+		}
+		return true;
+	}
+
+	/**
+	 * returns a WALImageReader
+	 */
+	public ImageReader createReaderInstance(Object extension)
+		throws IOException {
+		return new WALImageReader(this);
+	}
+
+	public String getDescription(Locale locale) {
+		return "id-software's Quake2 wal format for textures";
+	}
+}