java实现图片缩放、旋转和马赛克化

本文是作者结合网上的一些资料封装的java图片处理类，支持图片的缩放，旋转，马赛克化。

不多说，上代码：

package deal;

import java.awt.color;
import java.awt.graphics;
import java.awt.graphics2d;
import java.awt.image;
import java.awt.geom.affinetransform;
import java.awt.image.affinetransformop;
import java.awt.image.bufferedimage;
import java.io.file;

import javax.imageio.imageio;

/**
 * 图像处理类.
 * 
 * @author nagsh
 * 
 */
public class imagedeal {

  string openurl; // 原始图片打开路径
  string saveurl; // 新图保存路径
  string savename; // 新图名称
  string suffix; // 新图类型 只支持gif,jpg,png

  public imagedeal(string openurl, string saveurl, string savename,
      string suffix) {
    this.openurl = openurl;
    this.savename = savename;
    this.saveurl = saveurl;
    this.suffix = suffix;
  }

  /**
   * 图片缩放.
   * 
   * @param width
   *      需要的宽度
   * @param height
   *      需要的高度
   * @throws exception
   */
  public void zoom(int width, int height) throws exception {
    double sx = 0.0;
    double sy = 0.0;

    file file = new file(openurl);
    if (!file.isfile()) {
      throw new exception("imagedeal>>>" + file + " 不是一个图片文件!");
    }
    bufferedimage bi = imageio.read(file); // 读取该图片
    // 计算x轴y轴缩放比例--如需等比例缩放，在调用之前确保参数width和height是等比例变化的
    sx = (double) width / bi.getwidth();
    sy = (double) height / bi.getheight();

    affinetransformop op = new affinetransformop(
        affinetransform.getscaleinstance(sx, sy), null);
    file sf = new file(saveurl, savename + "." + suffix);
    image zoomimage = op.filter(bi, null);
    try {
      imageio.write((bufferedimage) zoomimage, suffix, sf); // 保存图片
    } catch (exception e) {
      e.printstacktrace();
    }

  }

  /**
   * 旋转
   * 
   * @param degree
   *      旋转角度
   * @throws exception
   */
  public void spin(int degree) throws exception {
    int swidth = 0; // 旋转后的宽度
    int sheight = 0; // 旋转后的高度
    int x; // 原点横坐标
    int y; // 原点纵坐标

    file file = new file(openurl);
    if (!file.isfile()) {
      throw new exception("imagedeal>>>" + file + " 不是一个图片文件!");
    }
    bufferedimage bi = imageio.read(file); // 读取该图片
    // 处理角度--确定旋转弧度
    degree = degree % 360;
    if (degree < 0)
      degree = 360 + degree;// 将角度转换到0-360度之间
    double theta = math.toradians(degree);// 将角度转为弧度

    // 确定旋转后的宽和高
    if (degree == 180 || degree == 0 || degree == 360) {
      swidth = bi.getwidth();
      sheight = bi.getheight();
    } else if (degree == 90 || degree == 270) {
      sheight = bi.getwidth();
      swidth = bi.getheight();
    } else {
      swidth = (int) (math.sqrt(bi.getwidth() * bi.getwidth()
          + bi.getheight() * bi.getheight()));
      sheight = (int) (math.sqrt(bi.getwidth() * bi.getwidth()
          + bi.getheight() * bi.getheight()));
    }

    x = (swidth / 2) - (bi.getwidth() / 2);// 确定原点坐标
    y = (sheight / 2) - (bi.getheight() / 2);

    bufferedimage spinimage = new bufferedimage(swidth, sheight,
        bi.gettype());
    // 设置图片背景颜色
    graphics2d gs = (graphics2d) spinimage.getgraphics();
    gs.setcolor(color.white);
    gs.fillrect(0, 0, swidth, sheight);// 以给定颜色绘制旋转后图片的背景

    affinetransform at = new affinetransform();
    at.rotate(theta, swidth / 2, sheight / 2);// 旋转图象
    at.translate(x, y);
    affinetransformop op = new affinetransformop(at,
        affinetransformop.type_bicubic);
    spinimage = op.filter(bi, spinimage);
    file sf = new file(saveurl, savename + "." + suffix);
    imageio.write(spinimage, suffix, sf); // 保存图片

  }
  /**
   * 马赛克化.
   * @param size 马赛克尺寸，即每个矩形的长宽
   * @return
   * @throws exception
   */
  public boolean mosaic(int size) throws exception {
    file file = new file(openurl);
    if (!file.isfile()) {
      throw new exception("imagedeal>>>" + file + " 不是一个图片文件!");
    }
    bufferedimage bi = imageio.read(file); // 读取该图片
    bufferedimage spinimage = new bufferedimage(bi.getwidth(),
        bi.getheight(), bi.type_int_rgb);
    if (bi.getwidth() < size || bi.getheight() < size || size <= 0) { // 马赛克格尺寸太大或太小
      return false;
    }

    int xcount = 0; // 方向绘制个数
    int ycount = 0; // y方向绘制个数
    if (bi.getwidth() % size == 0) {
      xcount = bi.getwidth() / size;
    } else {
      xcount = bi.getwidth() / size + 1;
    }
    if (bi.getheight() % size == 0) {
      ycount = bi.getheight() / size;
    } else {
      ycount = bi.getheight() / size + 1;
    }
    int x = 0;  //坐标
    int y = 0;
    // 绘制马赛克(绘制矩形并填充颜色)
    graphics gs = spinimage.getgraphics();
    for (int i = 0; i < xcount; i++) {
      for (int j = 0; j < ycount; j++) {
        //马赛克矩形格大小
         int mwidth = size;
         int mheight = size;
         if(i==xcount-1){  //横向最后一个比较特殊，可能不够一个size
           mwidth = bi.getwidth()-x;
         }
         if(j == ycount-1){ //同理
           mheight =bi.getheight()-y;
         }
       // 矩形颜色取中心像素点rgb值
        int centerx = x;
        int centery = y;
        if (mwidth % 2 == 0) {
          centerx += mwidth / 2;
        } else {
          centerx += (mwidth - 1) / 2;
        }
        if (mheight % 2 == 0) {
          centery += mheight / 2;
        } else {
          centery += (mheight - 1) / 2;
        }
        color color = new color(bi.getrgb(centerx, centery));
        gs.setcolor(color);
        gs.fillrect(x, y, mwidth, mheight);
        y = y + size;// 计算下一个矩形的y坐标
      }
      y = 0;// 还原y坐标
      x = x + size;// 计算x坐标
    }
    gs.dispose();
    file sf = new file(saveurl, savename + "." + suffix);
    imageio.write(spinimage, suffix, sf); // 保存图片
    return true;
  }

  public static void main(string[] args) throws exception {
    imagedeal imagedeal = new imagedeal("e://1.jpg", "e://", "2", "jpg");
    // 测试缩放
    /* imagedeal.zoom(200, 300); */
    // 测试旋转
    /* imagedeal.spin(90); */
    //测试马赛克
    /*imagedeal.mosaic(4);*/
  }

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。