Java中Image的水平翻转、缩放与自由旋转操作

骑猪看日落 2021-06-24 15:57 378阅读 0赞

bufferedimage.getColorModel().getTransparency()以获得原始图片透明度用于生成缓存图，在缓存图进行相应操作即可。

/**
         * 旋转图片为指定角度
         * 
         * @param bufferedimage
         *            目标图像
         * @param degree
         *            旋转角度
         * @return
         */
        public static BufferedImage rotateImage(final BufferedImage bufferedimage,
                final int degree) {
            int w = bufferedimage.getWidth();
            int h = bufferedimage.getHeight();
            int type = bufferedimage.getColorModel().getTransparency();
            BufferedImage img;
            Graphics2D graphics2d;
            (graphics2d = (img = new BufferedImage(w, h, type))
                    .createGraphics()).setRenderingHint(
                    RenderingHints.KEY_INTERPOLATION,
                    RenderingHints.VALUE_INTERPOLATION_BILINEAR);
            graphics2d.rotate(Math.toRadians(degree), w / 2, h / 2);
            graphics2d.drawImage(bufferedimage, 0, 0, null);
            graphics2d.dispose();
            return img;
        }
    
        /**
         * 变更图像为指定大小
         * 
         * @param bufferedimage
         *            目标图像
         * @param w
         *            宽
         * @param h
         *            高
         * @return
         */
        public static BufferedImage resizeImage(final BufferedImage bufferedimage,
                final int w, final int h) {
            int type = bufferedimage.getColorModel().getTransparency();
            BufferedImage img;
            Graphics2D graphics2d;
            (graphics2d = (img = createImage(w, h, type))
                    .createGraphics()).setRenderingHint(
                    RenderingHints.KEY_INTERPOLATION,
                    RenderingHints.VALUE_INTERPOLATION_BILINEAR);
            graphics2d.drawImage(bufferedimage, 0, 0, w, h, 0, 0, bufferedimage
                    .getWidth(), bufferedimage.getHeight(), null);
            graphics2d.dispose();
            return img;
        }
    
        /**
         * 水平翻转图像
         * 
         * @param bufferedimage 目标图像
         * @return
         */
        public static BufferedImage flipImage(final BufferedImage bufferedimage) {
            int w = bufferedimage.getWidth();
            int h = bufferedimage.getHeight();
            BufferedImage img;
            Graphics2D graphics2d;
            (graphics2d = (img = createImage(w, h, bufferedimage
                    .getColorModel().getTransparency())).createGraphics())
                    .drawImage(bufferedimage, 0, 0, w, h, w, 0, 0, h, null);
            graphics2d.dispose();
            return img;
        }