diff --git a/src/fr/pandacube/java/util/ColorUtil.java b/src/fr/pandacube/java/util/ColorUtil.java
new file mode 100644
index 0000000..45fe490
--- /dev/null
+++ b/src/fr/pandacube/java/util/ColorUtil.java
@@ -0,0 +1,49 @@
+package fr.pandacube.java.util;
+
+import java.awt.Color;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ColorUtil {
+	
+	/*
+	 * Rainbow
+	 */
+	private static List<Color> rainbowColors = new ArrayList<>();
+	
+	/**
+	 * Get a rainbow color
+	 * @param variation from 0 (include) to 1 (exclude).
+	 * 0 is red, 1/6 is yellow, 2/6 is green, 3/6 is cyan, 4/6 is blue, 5/6 is magenta
+	 * @return
+	 */
+	public static Color getRainbowColor(double variation) {
+		synchronized (rainbowColors) {
+			if (rainbowColors.isEmpty()) {
+				for (int g=0; g<255; g++) rainbowColors.add(new Color(255, g, 0));
+				for (int r=255; r>0; r--) rainbowColors.add(new Color(r, 255, 0));
+				for (int b=0; b<255; b++) rainbowColors.add(new Color(0, 255, b));
+				for (int g=255; g>0; g--) rainbowColors.add(new Color(0, g, 255));
+				for (int r=0; r<255; r++) rainbowColors.add(new Color(r, 0, 255));
+				for (int b=255; b>0; b--) rainbowColors.add(new Color(255, 0, b));
+			}
+		}
+		
+		while (variation >= 1) variation -= 1d;
+		while (variation < 0)  variation += 1d;
+		
+		return rainbowColors.get((int)(variation * rainbowColors.size()));
+	}
+	
+	
+	
+	
+	
+	
+	
+	
+	
+	
+	
+
+}
diff --git a/src/fr/pandacube/java/util/GifDecoder.java b/src/fr/pandacube/java/util/GifDecoder.java
new file mode 100644
index 0000000..dd1bad1
--- /dev/null
+++ b/src/fr/pandacube/java/util/GifDecoder.java
@@ -0,0 +1,787 @@
+package fr.pandacube.java.util;
+
+import java.net.URL;
+import java.util.ArrayList;
+import java.awt.AlphaComposite;
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.Graphics2D;
+import java.awt.Rectangle;
+import java.awt.image.BufferedImage;
+import java.awt.image.DataBufferInt;
+import java.io.BufferedInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * Class GifDecoder - Decodes a GIF file into one or more frames.
+ * <br><pre>
+ * Example:
+ *    GifDecoder d = new GifDecoder();
+ *    d.read("sample.gif");
+ *    int n = d.getFrameCount();
+ *    for (int i = 0; i < n; i++) {
+ *       BufferedImage frame = d.getFrame(i);  // frame i
+ *       int t = d.getDelay(i);  // display duration of frame in milliseconds
+ *       // do something with frame
+ *    }
+ * </pre>
+ * No copyright asserted on the source code of this class.  May be used for
+ * any purpose, however, refer to the Unisys LZW patent for any additional
+ * restrictions.  Please forward any corrections to questions at fmsware.com.
+ *
+ * @author Kevin Weiner, FM Software; LZW decoder adapted from John Cristy's ImageMagick.
+ * @version 1.03 November 2003
+ *
+ */
+
+public class GifDecoder {
+
+	/**
+	 * File read status: No errors.
+	 */
+	public static final int STATUS_OK = 0;
+
+	/**
+	 * File read status: Error decoding file (may be partially decoded)
+	 */
+	public static final int STATUS_FORMAT_ERROR = 1;
+
+	/**
+	 * File read status: Unable to open source.
+	 */
+	public static final int STATUS_OPEN_ERROR = 2;
+
+	protected BufferedInputStream in;
+	protected int status;
+
+	protected int width; // full image width
+	protected int height; // full image height
+	protected boolean gctFlag; // global color table used
+	protected int gctSize; // size of global color table
+	protected int loopCount = 1; // iterations; 0 = repeat forever
+
+	protected int[] gct; // global color table
+	protected int[] lct; // local color table
+	protected int[] act; // active color table
+
+	protected int bgIndex; // background color index
+	protected int bgColor; // background color
+	protected int lastBgColor; // previous bg color
+	protected int pixelAspect; // pixel aspect ratio
+
+	protected boolean lctFlag; // local color table flag
+	protected boolean interlace; // interlace flag
+	protected int lctSize; // local color table size
+
+	protected int ix, iy, iw, ih; // current image rectangle
+	protected Rectangle lastRect; // last image rect
+	protected BufferedImage image; // current frame
+	protected BufferedImage lastImage; // previous frame
+
+	protected byte[] block = new byte[256]; // current data block
+	protected int blockSize = 0; // block size
+
+	// last graphic control extension info
+	protected int dispose = 0;
+	// 0=no action; 1=leave in place; 2=restore to bg; 3=restore to prev
+	protected int lastDispose = 0;
+	protected boolean transparency = false; // use transparent color
+	protected int delay = 0; // delay in milliseconds
+	protected int transIndex; // transparent color index
+
+	protected static final int MaxStackSize = 4096;
+	// max decoder pixel stack size
+
+	// LZW decoder working arrays
+	protected short[] prefix;
+	protected byte[] suffix;
+	protected byte[] pixelStack;
+	protected byte[] pixels;
+
+	protected ArrayList<GifFrame> frames; // frames read from current file
+	protected int frameCount;
+
+	static class GifFrame {
+		public GifFrame(BufferedImage im, int del) {
+			image = im;
+			delay = del;
+		}
+		public BufferedImage image;
+		public int delay;
+	}
+
+	/**
+	 * Gets display duration for specified frame.
+	 *
+	 * @param n int index of frame
+	 * @return delay in milliseconds
+	 */
+	public int getDelay(int n) {
+		//
+		delay = -1;
+		if ((n >= 0) && (n < frameCount)) {
+			delay = ((GifFrame) frames.get(n)).delay;
+		}
+		return delay;
+	}
+
+	/**
+	 * Gets the number of frames read from file.
+	 * @return frame count
+	 */
+	public int getFrameCount() {
+		return frameCount;
+	}
+
+	/**
+	 * Gets the first (or only) image read.
+	 *
+	 * @return BufferedImage containing first frame, or null if none.
+	 */
+	public BufferedImage getImage() {
+		return getFrame(0);
+	}
+
+	/**
+	 * Gets the "Netscape" iteration count, if any.
+	 * A count of 0 means repeat indefinitiely.
+	 *
+	 * @return iteration count if one was specified, else 1.
+	 */
+	public int getLoopCount() {
+		return loopCount;
+	}
+
+	/**
+	 * Creates new frame image from current data (and previous
+	 * frames as specified by their disposition codes).
+	 */
+	protected void setPixels() {
+		// expose destination image's pixels as int array
+		int[] dest =
+			((DataBufferInt) image.getRaster().getDataBuffer()).getData();
+
+		// fill in starting image contents based on last image's dispose code
+		if (lastDispose > 0) {
+			if (lastDispose == 3) {
+				// use image before last
+				int n = frameCount - 2;
+				if (n > 0) {
+					lastImage = getFrame(n - 1);
+				} else {
+					lastImage = null;
+				}
+			}
+
+			if (lastImage != null) {
+				int[] prev =
+					((DataBufferInt) lastImage.getRaster().getDataBuffer()).getData();
+				System.arraycopy(prev, 0, dest, 0, width * height);
+				// copy pixels
+
+				if (lastDispose == 2) {
+					// fill last image rect area with background color
+					Graphics2D g = image.createGraphics();
+					Color c = null;
+					if (transparency) {
+						c = new Color(0, 0, 0, 0); 	// assume background is transparent
+					} else {
+						c = new Color(lastBgColor); // use given background color
+					}
+					g.setColor(c);
+					g.setComposite(AlphaComposite.Src); // replace area
+					g.fill(lastRect);
+					g.dispose();
+				}
+			}
+		}
+
+		// copy each source line to the appropriate place in the destination
+		int pass = 1;
+		int inc = 8;
+		int iline = 0;
+		for (int i = 0; i < ih; i++) {
+			int line = i;
+			if (interlace) {
+				if (iline >= ih) {
+					pass++;
+					switch (pass) {
+						case 2 :
+							iline = 4;
+							break;
+						case 3 :
+							iline = 2;
+							inc = 4;
+							break;
+						case 4 :
+							iline = 1;
+							inc = 2;
+					}
+				}
+				line = iline;
+				iline += inc;
+			}
+			line += iy;
+			if (line < height) {
+				int k = line * width;
+				int dx = k + ix; // start of line in dest
+				int dlim = dx + iw; // end of dest line
+				if ((k + width) < dlim) {
+					dlim = k + width; // past dest edge
+				}
+				int sx = i * iw; // start of line in source
+				while (dx < dlim) {
+					// map color and insert in destination
+					int index = ((int) pixels[sx++]) & 0xff;
+					int c = act[index];
+					if (c != 0) {
+						dest[dx] = c;
+					}
+					dx++;
+				}
+			}
+		}
+	}
+
+	/**
+	 * Gets the image contents of frame n.
+	 *
+	 * @return BufferedImage representation of frame, or null if n is invalid.
+	 */
+	public BufferedImage getFrame(int n) {
+		BufferedImage im = null;
+		if ((n >= 0) && (n < frameCount)) {
+			im = ((GifFrame) frames.get(n)).image;
+		}
+		return im;
+	}
+
+	/**
+	 * Gets image size.
+	 *
+	 * @return GIF image dimensions
+	 */
+	public Dimension getFrameSize() {
+		return new Dimension(width, height);
+	}
+
+	/**
+	 * Reads GIF image from stream
+	 *
+	 * @param BufferedInputStream containing GIF file.
+	 * @return read status code (0 = no errors)
+	 */
+	public int read(BufferedInputStream is) {
+		init();
+		if (is != null) {
+			in = is;
+			readHeader();
+			if (!err()) {
+				readContents();
+				if (frameCount < 0) {
+					status = STATUS_FORMAT_ERROR;
+				}
+			}
+		} else {
+			status = STATUS_OPEN_ERROR;
+		}
+		try {
+			is.close();
+		} catch (IOException e) {
+		}
+		return status;
+	}
+
+	/**
+	 * Reads GIF image from stream
+	 *
+	 * @param InputStream containing GIF file.
+	 * @return read status code (0 = no errors)
+	 */
+	public int read(InputStream is) {
+		init();
+		if (is != null) {
+			if (!(is instanceof BufferedInputStream))
+				is = new BufferedInputStream(is);
+			in = (BufferedInputStream) is;
+			readHeader();
+			if (!err()) {
+				readContents();
+				if (frameCount < 0) {
+					status = STATUS_FORMAT_ERROR;
+				}
+			}
+		} else {
+			status = STATUS_OPEN_ERROR;
+		}
+		try {
+			is.close();
+		} catch (IOException e) {
+		}
+		return status;
+	}
+
+	/**
+	 * Reads GIF file from specified file/URL source  
+	 * (URL assumed if name contains ":/" or "file:")
+	 *
+	 * @param name String containing source
+	 * @return read status code (0 = no errors)
+	 */
+	public int read(String name) {
+		status = STATUS_OK;
+		try {
+			name = name.trim().toLowerCase();
+			if ((name.indexOf("file:") >= 0) ||
+				(name.indexOf(":/") > 0)) {
+				URL url = new URL(name);
+				in = new BufferedInputStream(url.openStream());
+			} else {
+				in = new BufferedInputStream(new FileInputStream(name));
+			}
+			status = read(in);
+		} catch (IOException e) {
+			status = STATUS_OPEN_ERROR;
+		}
+
+		return status;
+	}
+
+	/**
+	 * Decodes LZW image data into pixel array.
+	 * Adapted from John Cristy's ImageMagick.
+	 */
+	protected void decodeImageData() {
+		int NullCode = -1;
+		int npix = iw * ih;
+		int available, 
+			clear,
+			code_mask,
+			code_size,
+			end_of_information,
+			in_code,
+			old_code,
+			bits,
+			code,
+			count,
+			i,
+			datum,
+			data_size,
+			first,
+			top,
+			bi,
+			pi;
+
+		if ((pixels == null) || (pixels.length < npix)) {
+			pixels = new byte[npix]; // allocate new pixel array
+		}
+		if (prefix == null) prefix = new short[MaxStackSize];
+		if (suffix == null) suffix = new byte[MaxStackSize];
+		if (pixelStack == null) pixelStack = new byte[MaxStackSize + 1];
+
+		//  Initialize GIF data stream decoder.
+
+		data_size = read();
+		clear = 1 << data_size;
+		end_of_information = clear + 1;
+		available = clear + 2;
+		old_code = NullCode;
+		code_size = data_size + 1;
+		code_mask = (1 << code_size) - 1;
+		for (code = 0; code < clear; code++) {
+			prefix[code] = 0;
+			suffix[code] = (byte) code;
+		}
+
+		//  Decode GIF pixel stream.
+
+		datum = bits = count = first = top = pi = bi = 0;
+
+		for (i = 0; i < npix;) {
+			if (top == 0) {
+				if (bits < code_size) {
+					//  Load bytes until there are enough bits for a code.
+					if (count == 0) {
+						// Read a new data block.
+						count = readBlock();
+						if (count <= 0)
+							break;
+						bi = 0;
+					}
+					datum += (((int) block[bi]) & 0xff) << bits;
+					bits += 8;
+					bi++;
+					count--;
+					continue;
+				}
+
+				//  Get the next code.
+
+				code = datum & code_mask;
+				datum >>= code_size;
+				bits -= code_size;
+
+				//  Interpret the code
+
+				if ((code > available) || (code == end_of_information))
+					break;
+				if (code == clear) {
+					//  Reset decoder.
+					code_size = data_size + 1;
+					code_mask = (1 << code_size) - 1;
+					available = clear + 2;
+					old_code = NullCode;
+					continue;
+				}
+				if (old_code == NullCode) {
+					pixelStack[top++] = suffix[code];
+					old_code = code;
+					first = code;
+					continue;
+				}
+				in_code = code;
+				if (code == available) {
+					pixelStack[top++] = (byte) first;
+					code = old_code;
+				}
+				while (code > clear) {
+					pixelStack[top++] = suffix[code];
+					code = prefix[code];
+				}
+				first = ((int) suffix[code]) & 0xff;
+
+				//  Add a new string to the string table,
+
+				if (available >= MaxStackSize) {
+					pixelStack[top++] = (byte) first;
+					continue;
+				}
+				pixelStack[top++] = (byte) first;
+				prefix[available] = (short) old_code;
+				suffix[available] = (byte) first;
+				available++;
+				if (((available & code_mask) == 0)
+					&& (available < MaxStackSize)) {
+					code_size++;
+					code_mask += available;
+				}
+				old_code = in_code;
+			}
+
+			//  Pop a pixel off the pixel stack.
+
+			top--;
+			pixels[pi++] = pixelStack[top];
+			i++;
+		}
+
+		for (i = pi; i < npix; i++) {
+			pixels[i] = 0; // clear missing pixels
+		}
+
+	}
+
+	/**
+	 * Returns true if an error was encountered during reading/decoding
+	 */
+	protected boolean err() {
+		return status != STATUS_OK;
+	}
+
+	/**
+	 * Initializes or re-initializes reader
+	 */
+	protected void init() {
+		status = STATUS_OK;
+		frameCount = 0;
+		frames = new ArrayList<>();
+		gct = null;
+		lct = null;
+	}
+
+	/**
+	 * Reads a single byte from the input stream.
+	 */
+	protected int read() {
+		int curByte = 0;
+		try {
+			curByte = in.read();
+		} catch (IOException e) {
+			status = STATUS_FORMAT_ERROR;
+		}
+		return curByte;
+	}
+
+	/**
+	 * Reads next variable length block from input.
+	 *
+	 * @return number of bytes stored in "buffer"
+	 */
+	protected int readBlock() {
+		blockSize = read();
+		int n = 0;
+		if (blockSize > 0) {
+			try {
+				int count = 0;
+				while (n < blockSize) {
+					count = in.read(block, n, blockSize - n);
+					if (count == -1) 
+						break;
+					n += count;
+				}
+			} catch (IOException e) {
+			}
+
+			if (n < blockSize) {
+				status = STATUS_FORMAT_ERROR;
+			}
+		}
+		return n;
+	}
+
+	/**
+	 * Reads color table as 256 RGB integer values
+	 *
+	 * @param ncolors int number of colors to read
+	 * @return int array containing 256 colors (packed ARGB with full alpha)
+	 */
+	protected int[] readColorTable(int ncolors) {
+		int nbytes = 3 * ncolors;
+		int[] tab = null;
+		byte[] c = new byte[nbytes];
+		int n = 0;
+		try {
+			n = in.read(c);
+		} catch (IOException e) {
+		}
+		if (n < nbytes) {
+			status = STATUS_FORMAT_ERROR;
+		} else {
+			tab = new int[256]; // max size to avoid bounds checks
+			int i = 0;
+			int j = 0;
+			while (i < ncolors) {
+				int r = ((int) c[j++]) & 0xff;
+				int g = ((int) c[j++]) & 0xff;
+				int b = ((int) c[j++]) & 0xff;
+				tab[i++] = 0xff000000 | (r << 16) | (g << 8) | b;
+			}
+		}
+		return tab;
+	}
+
+	/**
+	 * Main file parser.  Reads GIF content blocks.
+	 */
+	protected void readContents() {
+		// read GIF file content blocks
+		boolean done = false;
+		while (!(done || err())) {
+			int code = read();
+			switch (code) {
+
+				case 0x2C : // image separator
+					readImage();
+					break;
+
+				case 0x21 : // extension
+					code = read();
+					switch (code) {
+						case 0xf9 : // graphics control extension
+							readGraphicControlExt();
+							break;
+
+						case 0xff : // application extension
+							readBlock();
+							String app = "";
+							for (int i = 0; i < 11; i++) {
+								app += (char) block[i];
+							}
+							if (app.equals("NETSCAPE2.0")) {
+								readNetscapeExt();
+							}
+							else
+								skip(); // don't care
+							break;
+
+						default : // uninteresting extension
+							skip();
+					}
+					break;
+
+				case 0x3b : // terminator
+					done = true;
+					break;
+
+				case 0x00 : // bad byte, but keep going and see what happens
+					break;
+
+				default :
+					status = STATUS_FORMAT_ERROR;
+			}
+		}
+	}
+
+	/**
+	 * Reads Graphics Control Extension values
+	 */
+	protected void readGraphicControlExt() {
+		read(); // block size
+		int packed = read(); // packed fields
+		dispose = (packed & 0x1c) >> 2; // disposal method
+		if (dispose == 0) {
+			dispose = 1; // elect to keep old image if discretionary
+		}
+		transparency = (packed & 1) != 0;
+		delay = readShort() * 10; // delay in milliseconds
+		transIndex = read(); // transparent color index
+		read(); // block terminator
+	}
+
+	/**
+	 * Reads GIF file header information.
+	 */
+	protected void readHeader() {
+		String id = "";
+		for (int i = 0; i < 6; i++) {
+			id += (char) read();
+		}
+		if (!id.startsWith("GIF")) {
+			status = STATUS_FORMAT_ERROR;
+			return;
+		}
+
+		readLSD();
+		if (gctFlag && !err()) {
+			gct = readColorTable(gctSize);
+			bgColor = gct[bgIndex];
+		}
+	}
+
+	/**
+	 * Reads next frame image
+	 */
+	protected void readImage() {
+		ix = readShort(); // (sub)image position & size
+		iy = readShort();
+		iw = readShort();
+		ih = readShort();
+
+		int packed = read();
+		lctFlag = (packed & 0x80) != 0; // 1 - local color table flag
+		interlace = (packed & 0x40) != 0; // 2 - interlace flag
+		// 3 - sort flag
+		// 4-5 - reserved
+		lctSize = 2 << (packed & 7); // 6-8 - local color table size
+
+		if (lctFlag) {
+			lct = readColorTable(lctSize); // read table
+			act = lct; // make local table active
+		} else {
+			act = gct; // make global table active
+			if (bgIndex == transIndex)
+				bgColor = 0;
+		}
+		int save = 0;
+		if (transparency) {
+			save = act[transIndex];
+			act[transIndex] = 0; // set transparent color if specified
+		}
+
+		if (act == null) {
+			status = STATUS_FORMAT_ERROR; // no color table defined
+		}
+
+		if (err()) return;
+
+		decodeImageData(); // decode pixel data
+		skip();
+
+		if (err()) return;
+
+		frameCount++;
+
+		// create new image to receive frame data
+		image =
+			new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB_PRE);
+
+		setPixels(); // transfer pixel data to image
+
+		frames.add(new GifFrame(image, delay)); // add image to frame list
+
+		if (transparency) {
+			act[transIndex] = save;
+		}
+		resetFrame();
+
+	}
+
+	/**
+	 * Reads Logical Screen Descriptor
+	 */
+	protected void readLSD() {
+
+		// logical screen size
+		width = readShort();
+		height = readShort();
+
+		// packed fields
+		int packed = read();
+		gctFlag = (packed & 0x80) != 0; // 1   : global color table flag
+		// 2-4 : color resolution
+		// 5   : gct sort flag
+		gctSize = 2 << (packed & 7); // 6-8 : gct size
+
+		bgIndex = read(); // background color index
+		pixelAspect = read(); // pixel aspect ratio
+	}
+
+	/**
+	 * Reads Netscape extenstion to obtain iteration count
+	 */
+	protected void readNetscapeExt() {
+		do {
+			readBlock();
+			if (block[0] == 1) {
+				// loop count sub-block
+				int b1 = ((int) block[1]) & 0xff;
+				int b2 = ((int) block[2]) & 0xff;
+				loopCount = (b2 << 8) | b1;
+			}
+		} while ((blockSize > 0) && !err());
+	}
+
+	/**
+	 * Reads next 16-bit value, LSB first
+	 */
+	protected int readShort() {
+		// read 16-bit value, LSB first
+		return read() | (read() << 8);
+	}
+
+	/**
+	 * Resets frame state for reading next image.
+	 */
+	protected void resetFrame() {
+		lastDispose = dispose;
+		lastRect = new Rectangle(ix, iy, iw, ih);
+		lastImage = image;
+		lastBgColor = bgColor;
+		/*int dispose = 0;
+		boolean transparency = false;
+		int delay = 0;*/
+		lct = null;
+	}
+
+	/**
+	 * Skips variable length blocks up to and including
+	 * next zero length block.
+	 */
+	protected void skip() {
+		do {
+			readBlock();
+		} while ((blockSize > 0) && !err());
+	}
+}
\ No newline at end of file