ImageWrapper img = null;
ImageFormat format = ImageUtils.identifyFormat(input);
if(format == null) {
throw new IllegalArgumentException("Unsupported image format, only JPEG, GIF, PNG, BMP and TIFF are supported");
}
ByteArraySeekableStreamWrap wrap = null;
wrap = ByteArraySeekableStreamWrap.wrapInputStream(input);
/**
* 利用JAI读取源图片
*/