Image :: read/write TGA

public static BufferedImage readTGA(File file) throws IOException
   {
      if (!file.exists())
         throw new FileNotFoundException(file.getAbsolutePath());

      byte[] header = new byte[18];
      int len = (int) file.length() - header.length;
      if (len < 0)
         throw new IllegalStateException("file not big enough to contain header: " + file.getAbsolutePath());
      byte[] data = new byte[len];

      RandomAccessFile raf = new RandomAccessFile(file, "r");
      raf.read(header);
      raf.read(data);
      raf.close();

      if ((header[0] | header[1]) != 0)
         throw new IllegalStateException(file.getAbsolutePath());
      if (header[2] != 2)
         throw new IllegalStateException(file.getAbsolutePath());
      int w = 0, h = 0;
      w |= (header[12] & 0xFF) << 0;
      w |= (header[13] & 0xFF) << 8;
      h |= (header[14] & 0xFF) << 0;
      h |= (header[15] & 0xFF) << 8;

      boolean alpha;
      if ((w * h) * 3 == data.length)
         alpha = false;
      else if ((w * h) * 4 == data.length)
         alpha = true;
      else
         throw new IllegalStateException(file.getAbsolutePath());
      if (!alpha && (header[16] != 24))
         throw new IllegalStateException(file.getAbsolutePath());
      if (alpha && (header[16] != 32))
         throw new IllegalStateException(file.getAbsolutePath());
      if ((header[17] & 15) != (alpha ? 8 : 0))
         throw new IllegalStateException(file.getAbsolutePath());

      BufferedImage dst = new BufferedImage(w, h, alpha ? BufferedImage.TYPE_INT_ARGB : BufferedImage.TYPE_INT_RGB);
      int[] pixels = ((DataBufferInt) dst.getRaster().getDataBuffer()).getData();
      if (pixels.length != w * h)
         throw new IllegalStateException(file.getAbsolutePath());
      if (data.length != pixels.length * (alpha ? 4 : 3))
         throw new IllegalStateException(file.getAbsolutePath());

      if (alpha)
      {
         for (int i = 0, p = (pixels.length - 1) * 4; i < pixels.length; i++, p -= 4)
         {
            pixels[i] |= ((data[p + 0]) & 0xFF) << 0;
            pixels[i] |= ((data[p + 1]) & 0xFF) << 8;
            pixels[i] |= ((data[p + 2]) & 0xFF) << 16;
            pixels[i] |= ((data[p + 3]) & 0xFF) << 24;
         }
      }
      else
      {
         for (int i = 0, p = (pixels.length - 1) * 3; i < pixels.length; i++, p -= 3)
         {
            pixels[i] |= ((data[p + 0]) & 0xFF) << 0;
            pixels[i] |= ((data[p + 1]) & 0xFF) << 8;
            pixels[i] |= ((data[p + 2]) & 0xFF) << 16;
         }
      }

      if ((header[17] >> 4) == 1)
      {
         // ok
      }
      else if ((header[17] >> 4) == 0)
      {
         // flip horizontally

         for (int y = 0; y < h; y++)
         {
            int w2 = w / 2;
            for (int x = 0; x < w2; x++)
            {
               int a = (y * w) + x;
               int b = (y * w) + (w - 1 - x);
               int t = pixels[a];
               pixels[a] = pixels[b];
               pixels[b] = t;
            }
         }
      }
      else
      {
         throw new UnsupportedOperationException(file.getAbsolutePath());
      }

      return dst;
   }

   public static void writeTGA(BufferedImage src, File file) throws IOException
   {
      DataBuffer buffer = src.getRaster().getDataBuffer();
      boolean alpha = src.getColorModel().hasAlpha();
      byte[] data;

      if (buffer instanceof DataBufferByte)
      {
         byte[] pixels = ((DataBufferByte) src.getRaster().getDataBuffer()).getData();
         if (pixels.length != src.getWidth() * src.getHeight() * (alpha ? 4 : 3))
            throw new IllegalStateException();

         data = new byte[pixels.length];

         for (int i = 0, p = pixels.length - 1; i < data.length; i++, p--)
         {
            data[i] = pixels[p];
         }
      }
      else if (buffer instanceof DataBufferInt)
      {
         int[] pixels = ((DataBufferInt) src.getRaster().getDataBuffer()).getData();
         if (pixels.length != src.getWidth() * src.getHeight())
            throw new IllegalStateException();

         data = new byte[pixels.length * (alpha ? 4 : 3)];

         if (alpha)
         {
            for (int i = 0, p = pixels.length - 1; i < data.length; i += 4, p--)
            {
               data[i + 0] = (byte) ((pixels[p] >> 0) & 0xFF);
               data[i + 1] = (byte) ((pixels[p] >> 8) & 0xFF);
               data[i + 2] = (byte) ((pixels[p] >> 16) & 0xFF);
               data[i + 3] = (byte) ((pixels[p] >> 24) & 0xFF);
            }
         }
         else
         {
            for (int i = 0, p = pixels.length - 1; i < data.length; i += 3, p--)
            {
               data[i + 0] = (byte) ((pixels[p] >> 0) & 0xFF);
               data[i + 1] = (byte) ((pixels[p] >> 8) & 0xFF);
               data[i + 2] = (byte) ((pixels[p] >> 16) & 0xFF);
            }
         }
      }
      else
      {
         throw new UnsupportedOperationException();
      }

      byte[] header = new byte[18];
      header[2] = 2; // uncompressed, true-color image
      header[12] = (byte) ((src.getWidth() >> 0) & 0xFF);
      header[13] = (byte) ((src.getWidth() >> 8) & 0xFF);
      header[14] = (byte) ((src.getHeight() >> 0) & 0xFF);
      header[15] = (byte) ((src.getHeight() >> 8) & 0xFF);
      header[16] = (byte) (alpha ? 32 : 24); // bits per pixel
      header[17] = (byte) ((alpha ? 8 : 0) | (1 << 4));

      RandomAccessFile raf = new RandomAccessFile(file, "rw");
      raf.write(header);
      raf.write(data);
      raf.setLength(raf.getFilePointer()); // trim
      raf.close();
   }