老生常谈了，直接看代码。
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;
}
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; }
本文转自 cping 51CTO博客，原文链接:http://blog.51cto.com/cping1982/130066
