干货分享，图片模糊算法，解析xml绘制图片

package com.metek.blur; import android.content.Context; import android.graphics.Bitmap; public class BlurUtils { /** * Android api 17实现的虚化 * 某些机型上可能会Crash * * @param context * @param sentBitmap * @param radius 大于1小于等于25 * @return */ public static Bitmap fastblur(Context context, Bitmap sentBitmap, int radius) { if (sentBitmap == null) { return null; } // if (Build.VERSION.SDK_INT > 16) { // Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true); // // final RenderScript rs = RenderScript.create(context); // final Allocation input = Allocation.createFromBitmap(rs, // sentBitmap, Allocation.MipmapControl.MIPMAP_NONE, // Allocation.USAGE_SCRIPT); // final Allocation output = Allocation.createTyped(rs, // input.getType()); // final ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(rs, // Element.U8_4(rs)); // script.setRadius(radius /* e.g. 3.f */); // script.setInput(input); // script.forEach(output); // output.copyTo(bitmap); // return bitmap; // } return stackblur(sentBitmap, radius); } /** * 纯Java实现的虚化，适用老版本api，外部只需调fastblur，会自动判断 * * @param sentBitmap * @param radius * @return */ private static Bitmap stackblur(Bitmap sentBitmap, int radius) { Bitmap bitmap = null; try { bitmap = sentBitmap.copy(sentBitmap.getConfig(), true); } catch (OutOfMemoryError e) { e.printStackTrace(); return sentBitmap; } 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); } }

package com.metek.blur; import java.io.FileNotFoundException; import java.io.FileOutputStream; import android.content.Context; import android.content.res.XmlResourceParser; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Paint; import android.os.AsyncTask; import android.os.SystemClock; import android.util.DisplayMetrics; /** * 生成天气模糊背景图 * */ public class BlurWeatherImage { private static final String TAG = "BlurWeatherImage"; private Bitmap bitmap = null; private Paint paint; private Canvas canvas; private FileOutputStream out = null; private float wRate; private float hRate; private int width; private int height; private Context context; private static final String IMAGENAME="ani_cloudy_night.png"; public BlurWeatherImage(Context context) { super(); this.context = context; DisplayMetrics dm = context.getResources().getDisplayMetrics(); width = dm.widthPixels; height = dm.heightPixels; bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888); paint = new Paint(Paint.ANTI_ALIAS_FLAG); canvas = new Canvas(bitmap); wRate = width / 720f; hRate = height / 1280f; } /** 模糊图片 */ public void blurImage() { BulurAsyncTask bat = new BulurAsyncTask(); bat.execute(); } class BulurAsyncTask extends AsyncTask<Void, Void, Void> { protected Void doInBackground(Void... params) { analysisXml(); return null; } protected void onPostExecute(Void result) { super.onPostExecute(result); listener.drawEnd(); } } public void analysisXml() { canvas.drawColor(0xff102d37); XmlResourceParser parser = context.getResources().getXml(R.xml.ani_cloudy_night); try { int event = parser.getEventType(); while (event != XmlResourceParser.END_DOCUMENT) { String tagName = parser.getName(); if (event == XmlResourceParser.START_TAG) { if (tagName.equals("view")) { int x = Integer.parseInt(parser.getAttributeValue(null, "x")); int y = Integer.parseInt(parser.getAttributeValue(null, "y")); int w = Integer.parseInt(parser.getAttributeValue(null, "w")); int h = Integer.parseInt(parser.getAttributeValue(null, "h")); String residname = parser.getAttributeValue(null, "resid"); int resid = context.getResources().getIdentifier(residname.replace("@drawable/", ""), "drawable", context.getPackageName()); picture(bitmap, x, y, w, h, resid); SystemClock.sleep(100); } } event = parser.next(); } } catch (Exception e) { e.printStackTrace(); } try { out = context.openFileOutput(IMAGENAME, Context.MODE_PRIVATE); bitmap.compress(Bitmap.CompressFormat.PNG, 100, out); out = context.openFileOutput("blur_"+IMAGENAME, Context.MODE_PRIVATE); Bitmap blurBitmap = BlurUtils.fastblur(context, bitmap, 80); blurBitmap.compress(Bitmap.CompressFormat.PNG, 100, out); android.util.Log.i(TAG, IMAGENAME + "writer success"); } catch (FileNotFoundException e) { e.printStackTrace(); } } /** * @param x * 元素x坐标 * @param y * 元素y坐标 * @param w * 元素宽度 * @param h * 元素高度 * @param resId * 资源id */ public void picture(Bitmap bitmap, int x, int y, int w, int h, int resId) { Bitmap element = BitmapFactory.decodeResource(context.getResources(), resId); int scaleW = (int) (w * wRate); int scaleH = (int) (h * hRate); Bitmap scaled = Bitmap.createScaledBitmap(element, scaleW, scaleH, false); canvas.drawBitmap(scaled, x * wRate, y * hRate, paint); } private OnDrawListener listener; public interface OnDrawListener { /** 绘图结束 */ public void drawEnd(); } public void setOnDrawListener(OnDrawListener listener) { this.listener = listener; } }