Android处理图像数据转换的各种方法

android中处理图像是一件很常见的事情，这里记录备忘一些亲身使用过的处理图片数据的方法。

转为bitmap

rgb值转bitmap

private bitmap createcolorbitmap(string rgb, int width, int height) {
      bitmap bmp = bitmap.createbitmap(width, height, bitmap.config.argb_8888);
      int color = color.parsecolor(rgb);
      bmp.erasecolor(color);
      return bmp;
}

//usage
bitmap bmp = createcolorbitmap("#cce8cf", 200, 50);

color值转bitmap

private bitmap createcolorbitmap(int color, int width, int height) {
  bitmap bmp = bitmap.createbitmap(width, height, bitmap.config.argb_8888);
  bmp.erasecolor(color);
  return bmp;
}
//usage
bitmap bmp = createcolorbitmap(color.blue, 200, 50);

字节数组转bitmap

private bitmap getbitmapfrombytearray(byte[] array) {
  return bitmapfactory.decodebytearray(array, 0, array.length);
}

读取文件转bitmap

private bitmap getbitmapfromfile(string pathname) {
      return bitmapfactory.decodefile(pathname);
}

读取资源转bitmap

private bitmap getbitmapfromresource(resources res, int resid) {
      return bitmapfactory.decoderesource(res, resid);
  }

输入流转bitmap

private bitmap getbitmapfromstream(inputstream inputstream) {
      return bitmapfactory.decodestream(inputstream);
}

drawable转bitmap

bitmap icon = bitmapfactory.decoderesource(context.getresources(),r.drawable.icon_resource);

转为drawable

资源转drawable

drawable drawable = getresources().getdrawable(r.drawable.ic_launcher);

bitmap转drawable

drawable d = new bitmapdrawable(getresources(),bitmap);

图片圆角展示

通过对图片数据bitmap进行处理即可，其中pixels为边角的半径。

public static bitmap getroundedcornerbitmap(bitmap bitmap, int pixels) {
        bitmap output = bitmap.createbitmap(bitmap.getwidth(), bitmap
                .getheight(), config.argb_8888);
        canvas canvas = new canvas(output);

        final int color = 0xff424242;
        final paint paint = new paint();
        final rect rect = new rect(0, 0, bitmap.getwidth(), bitmap.getheight());
        final rectf rectf = new rectf(rect);
        final float roundpx = pixels;

        paint.setantialias(true);
        canvas.drawargb(0, 0, 0, 0);
        paint.setcolor(color);
        canvas.drawroundrect(rectf, roundpx, roundpx, paint);

        paint.setxfermode(new porterduffxfermode(mode.src_in));
        canvas.drawbitmap(bitmap, rect, rect, paint);

        return output;
    }