j2me MIDP2.0 下实现的图片缩放函数

    /**
    * 图片缩放函数
     * @param src 原图片
     * @param desW 缩放后的宽度
     * @param desH 缩放后的高度
     * @return 缩放后的图片
     */
    public static Image ZoomImage(Image src, int desW, int desH){
        Image desImg = null;
        int srcW = src.getWidth(); // 原始图像宽
        int srcH = src.getHeight(); // 原始图像高
        int[] srcBuf = new int[srcW * srcH]; // 原始图片像素信息缓存

        src.getRGB(srcBuf, 0, srcW, 0, 0, srcW, srcH);

        // 计算插值表
        int[] tabY = new int[desH];
        int[] tabX = new int[desW];

        int sb = 0;
        int db = 0;
        int tems = 0;
        int temd = 0;
        int distance = srcH > desH ? srcH : desH;
        for (int i = 0; i <= distance; i++) { /* 垂直方向 */
            tabY[db] = sb;
            tems += srcH;
            temd += desH;
            if (tems > distance) {
                tems -= distance;
                sb++;
            }
            if (temd > distance) {
                temd -= distance;
                db++;
            }
        }

        sb = 0;
        db = 0;
        tems = 0;
        temd = 0;
        distance = srcW > desW ? srcW : desW;
        for (int i = 0; i <= distance; i++) { /* 水平方向 */
            tabX[db] = (short) sb;
            tems += srcW;
            temd += desW;
            if (tems > distance) {
                tems -= distance;
                sb++;
            }
            if (temd > distance) {
                temd -= distance;
                db++;
            }
        }

        // 生成放大缩小后图形像素buf
        int[] desBuf = new int[desW * desH];
        int dx = 0;
        int dy = 0;
        int sy = 0;
        int oldy = -1;
        for (int i = 0; i < desH; i++) {
            if (oldy == tabY[i]) {
                System.arraycopy(desBuf, dy - desW, desBuf, dy, desW);
            } else {
                dx = 0;
                for (int j = 0; j < desW; j++) {
                    desBuf[dy + dx] = srcBuf[sy + tabX[j]];
                    dx++;
                }
                sy += (tabY[i] - oldy) * srcW;
            }
            oldy = tabY[i];
            dy += desW;
        }

        // 生成图片
        desImg = Image.createRGBImage(desBuf, desW, desH, false);
        return desImg;
    }