Bug 196272 Text position is incorrect in postscript and ppt.
Text position need to be ajusted according to baseline position.
engine/org.eclipse.birt.report.engine.emitter.postscript/src/org/eclipse/birt/report/engine/emitter/postscript/PostscriptWriter.java
Image image = ImageIO.read( imageStream );
		drawImage( image, x, y, width, height, null );
	}
	/**
	 * Draws a image with specified image data, position, size and background
	 * color.
	 * 
	 * @param image
	 *            the source image data.
	 * @param x
	 *            the x position.
	 * @param y
	 *            the y position.
	 * @param width
	 *            the image width.
	 * @param height
	 *            the image height.
	 * @param bgcolor
	 *            the background color.
	 * @throws Exception
	 */
	public void drawImage( Image image, float x, float y, float width,
			float height, Color bgcolor ) throws Exception
	{
		if ( image == null )
		{
			throw new IllegalArgumentException( "null image." );
		}
		ImageSource imageSource = getImageSource( image );
		drawImage( imageSource, x, y, width, height, bgcolor );