图片打水印和缩放:
public final static BufferedImage[] pressImage(InputStream srcImg, String waterImg,float alpha) throws IOException {
//File file = new File(targetImg);
Image image = ImageIO.read(srcImg);
int width = image.getWidth(null);
int height = image.getHeight(null);
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bufferedImage.createGraphics();
g.drawImage(image, 0, 0, width, height, null);
Image waterImage = ImageIO.read(new File(waterImg)); // 水印文件
int width_1 = waterImage.getWidth(null);
int height_1 = waterImage.getHeight(null);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
int div=(int) (0.1*width_1);
for(int y=0,row=0;y图片的缩放使用了Thumbnails这个工具,(事实上它也能够用来打水印的,只是我还没有研究)
jar 包或者maven 请自行搜索
须要特别注意的是 Thumbnails 默认是依照等比例进行缩放的而且它的缩放规则是:
如果 把图片所放到 200*300
* 若图片横比200小。高比300小。不变
* 若图片横比200小，高比300大。高缩小到300，图片比例不变
* 若图片横比200大，高比300小。横缩小到200。图片比例不变
* 若图片横比200大，高比300大。图片按比例缩小，横为200或高为300
bufferInage转换 inputSteam
private InputStream getInputstreamFromBufferedImage(BufferedImage img) throws IOException{
ByteArrayOutputStream bs =new ByteArrayOutputStream();
ImageOutputStream imOut =ImageIO.createImageOutputStream(bs);
ImageIO.write(img,"jpg",imOut); //scaledImage1为BufferedImage，jpg为图像的类型
InputStream is =new ByteArrayInputStream(bs.toByteArray());
return is;
}版权声明：本文博主原创文章，博客，未经同意不得转载。