Android模糊处理实现图片毛玻璃效果

本文实例讲解了Android 虚化图片、模糊图片、图片毛玻璃效果的实现方法，具体内容如下
效果如图：

在Android可以用RenderScript方便的实现这个方法：

private void blur（Bitmap bkg, View view, float radius） { Bitmap overlay = Bitmap.createBitmap（view.getMeasuredWidth（）, view.getMeasuredHeight（）, Bitmap.Config.ARGB_8888）; Canvas canvas = new Canvas（overlay）; canvas.drawBitmap（bkg, -view.getLeft（）, -view.getTop（）, null）; RenderScript rs = RenderScript.create（this）; Allocation overlayAlloc = Allocation.createFromBitmap（rs, overlay）; ScriptIntrinsicBlur blur = ScriptIntrinsicBlur.create（rs, overlayAlloc.getElement（））; blur.setInput（overlayAlloc）; blur.setRadius（radius）; blur.forEach（overlayAlloc）; overlayAlloc.copyTo（overlay）; view.setBackground（new BitmapDrawable（getResources（）, overlay））; rs.destroy（）;}

但是RenderScript的这个方法需要Android API17，也就说需要在Android 4.2上才能实现。
低于Android4.2可以用Java原生代码实现。但是效率会低不少：这完全是一种妥协的方式，不推荐。

/* * This method was copied from http://stackoverflow.com/a/10028267/694378. * The only modifications I"ve made are to remove a couple of Log * statements which could slow things down slightly. */public Bitmap fastblur（Bitmap sentBitmap, int radius） {// Stack Blur v1.0 from // http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html // // Java Author: Mario Klingemann <mario at quasimondo.com> // http://incubator.quasimondo.com // created Feburary 29, 2004 // Android port : Yahel Bouaziz <yahel at kayenko.com> // http://www.kayenko.com // ported april 5th, 2012// This is a compromise between Gaussian Blur and Box blur // It creates much better looking blurs than Box Blur, but is // 7x faster than my Gaussian Blur implementation. // // I called it Stack Blur because this describes best how this // filter works internally: it creates a kind of moving stack // of colors whilst scanning through the image. Thereby it // just has to add one new block of color to the right side // of the stack and remove the leftmost color. The remaining // colors on the topmost layer of the stack are either added on // or reduced by one, depending on if they are on the right or // on the left side of the stack. // // If you are using this algorithm in your code please add // the following line: // // Stack Blur Algorithm by Mario Klingemann <mario@quasimondo.com>Bitmap bitmap = sentBitmap.copy（sentBitmap.getConfig（）, true）;if （radius < 1） {return （null）; }int w = bitmap.getWidth（）; int h = bitmap.getHeight（）;int[] pix = new int[w * h]; bitmap.getPixels（pix, 0, w, 0, 0, w, h）;int wm = w - 1; int hm = h - 1; int wh = w * h; int div = radius + radius + 1;int r[] = new int[wh]; int g[] = new int[wh]; int b[] = new int[wh]; int rsum, gsum, bsum, x, y, i, p, yp, yi, yw; int vmin[] = new int[Math.max（w, h）];int divsum = （div + 1） >> 1; divsum *= divsum; int dv[] = new int[256 * divsum]; for （i = 0; i < 256 * divsum; i++） {dv[i] = （i / divsum）; }yw = yi = 0;int[][] stack = new int[div][3]; int stackpointer; int stackstart; int[] sir; int rbs; int r1 = radius + 1; int routsum, goutsum, boutsum; int rinsum, ginsum, binsum;for （y = 0; y < h; y++） {rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;for （i = -radius; i <= radius; i++） { p = pix[yi + Math.min（wm, Math.max（i, 0））]; sir = stack[i + radius]; sir[0] = （p & 0xff0000） >> 16; sir[1] = （p & 0x00ff00） >> 8; sir[2] = （p & 0x0000ff）; rbs = r1 - Math.abs（i）; rsum += sir[0] * rbs; gsum += sir[1] * rbs; bsum += sir[2] * rbs; if （i > 0） {rinsum += sir[0];ginsum += sir[1];binsum += sir[2]; } else {routsum += sir[0];goutsum += sir[1];boutsum += sir[2]; }}stackpointer = radius; for （x = 0; x < w; x++） {r[yi] = dv[rsum]; g[yi] = dv[gsum]; b[yi] = dv[bsum];rsum -= routsum; gsum -= goutsum; bsum -= boutsum;stackstart = stackpointer - radius + div; sir = stack[stackstart % div];routsum -= sir[0]; goutsum -= sir[1]; boutsum -= sir[2];if （y == 0） {vmin[x] = Math.min（x + radius + 1, wm）; } p = pix[yw + vmin[x]];sir[0] = （p & 0xff0000） >> 16; sir[1] = （p & 0x00ff00） >> 8; sir[2] = （p & 0x0000ff）;rinsum += sir[0]; ginsum += sir[1]; binsum += sir[2];rsum += rinsum; gsum += ginsum; bsum += binsum;stackpointer = （stackpointer + 1） % div; sir = stack[（stackpointer） % div];routsum += sir[0]; goutsum += sir[1]; boutsum += sir[2];rinsum -= sir[0]; ginsum -= sir[1]; binsum -= sir[2];yi++;}yw += w; } for （x = 0; x < w; x++） {rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;yp = -radius * w;for （i = -radius; i <= radius; i++） { yi = Math.max（0, yp） + x;sir = stack[i + radius];sir[0] = r[yi]; sir[1] = g[yi]; sir[2] = b[yi];rbs = r1 - Math.abs（i）;rsum += r[yi] * rbs; gsum += g[yi] * rbs; bsum += b[yi] * rbs;if （i > 0） {rinsum += sir[0];ginsum += sir[1];binsum += sir[2]; } else {routsum += sir[0];goutsum += sir[1];boutsum += sir[2]; }if （i < hm） {yp += w; }}yi = x;stackpointer = radius;for （y = 0; y < h; y++） { // Preserve alpha channel: （ 0xff000000 & pix[yi] ） pix[yi] = （ 0xff000000 & pix[yi] ） | （ dv[rsum] << 16 ） | （ dv[gsum] << 8 ） | dv[bsum];rsum -= routsum; gsum -= goutsum; bsum -= boutsum;stackstart = stackpointer - radius + div; sir = stack[stackstart % div];routsum -= sir[0]; goutsum -= sir[1]; boutsum -= sir[2];if （x == 0） {vmin[y] = Math.min（y + r1, hm） * w; } p = x + vmin[y];sir[0] = r[p]; sir[1] = g[p]; sir[2] = b[p];rinsum += sir[0]; ginsum += sir[1]; binsum += sir[2];rsum += rinsum; gsum += ginsum; bsum += binsum;stackpointer = （stackpointer + 1） % div; sir = stack[stackpointer];routsum += sir[0]; goutsum += sir[1]; boutsum += sir[2];rinsum -= sir[0]; ginsum -= sir[1]; binsum -= sir[2];yi += w;} }bitmap.setPixels（pix, 0, w, 0, 0, w, h）;return （bitmap）;}

以上就是本文的全部内容，希望对大家学习Android软件编程有所帮助。