public void Write(OutputStream output) throws IOException {
BitUtils.WriteWord(output, localScreenWidth_);
BitUtils.WriteWord(output, localScreenHeight_);
output.write(byte_);
output.write(backgroundColorIndex_);
output.write(pixelAspectRatio_);
}
public void Write(OutputStream output) throws IOException {
output.write(separator_);
BitUtils.WriteWord(output, leftPosition_);
BitUtils.WriteWord(output, topPosition_);
BitUtils.WriteWord(output, width_);
BitUtils.WriteWord(output, height_);
output.write(byte_);
}
void ToIndexedColor(byte r[][], byte g[][], byte b[][]) throws AWTException {
pixels_ = new byte[width_ * height_];
colors_ = new byte[256 * 3];
int colornum = 0;
for (int x = 0; x < width_; ++x) {
for (int y = 0; y < height_; ++y) {
int search;
for (search = 0; search < colornum; ++search)
if (colors_[search * 3] == r[x][y]
&& colors_[search * 3 + 1] == g[x][y]
&& colors_[search * 3 + 2] == b[x][y]) break;
if (search > 255) throw new AWTException("Too many colors.");
pixels_[y * width_ + x] = (byte) search;
if (search == colornum) {
colors_[search * 3] = r[x][y];
colors_[search * 3 + 1] = g[x][y];
colors_[search * 3 + 2] = b[x][y];
++colornum;
}
}
}
numColors_ = 1 << BitUtils.BitsNeeded(colornum);
byte copy[] = new byte[numColors_ * 3];
System.arraycopy(colors_, 0, copy, 0, numColors_ * 3);
colors_ = copy;
}
public ScreenDescriptor(short width, short height, int numColors) {
localScreenWidth_ = width;
localScreenHeight_ = height;
SetGlobalColorTableSize((byte) (BitUtils.BitsNeeded(numColors) - 1));
SetGlobalColorTableFlag((byte) 1);
SetSortFlag((byte) 0);
SetColorResolution((byte) 7);
backgroundColorIndex_ = 0;
pixelAspectRatio_ = 0;
}
/**
* Writes the image out to a stream in the GIF file format. This will be a single GIF87a image,
* non-interlaced, with no background color. <B>This may take some time.</B>
*
* <p>
*
* @param output The stream to output to. This should probably be a buffered stream.
* @exception IOException Will be thrown if a write operation fails.
*/
public void Write(OutputStream output) throws IOException {
BitUtils.WriteString(output, "GIF87a");
ScreenDescriptor sd = new ScreenDescriptor(width_, height_, numColors_);
sd.Write(output);
output.write(colors_, 0, colors_.length);
ImageDescriptor id = new ImageDescriptor(width_, height_, ',');
id.Write(output);
byte codesize = BitUtils.BitsNeeded(numColors_);
if (codesize == 1) ++codesize;
output.write(codesize);
LZWCompressor.LZWCompress(output, codesize, pixels_);
output.write(0);
id = new ImageDescriptor((byte) 0, (byte) 0, ';');
id.Write(output);
output.flush();
}