Android RenderScript实现高斯模糊

private SeekBar blurSeekBar;//拖动条private ImageView img_blur;//显示模糊后bitmap的ImageView//原bitmap和高斯模糊后的bitmapprivate Bitmap bitmap_original, bitmap_blur;//高斯模糊处理的AsyncTaskprivate RenderScriptTask mLatestTask = null;//RenderScript 对象（Google的高性能并行计算类，他可以利用设备的GPU/CPU等计算资源）private RenderScript mRS;//下面是两个RenderScript的传入参数对象private Allocation mInAllocation;private Allocation mOutAllocation;//高斯模糊处理实例private ScriptIntrinsicBlur mScriptBlur;

@Overrideprotected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  blurSeekBar = (SeekBar) findViewById(R.id.aty_main_seekBar);  img_blur = (ImageView) findViewById(R.id.aty_main_img_blur);  bitmap_original = loadBitmap(R.drawable.meet_entry_guide_3);  // 复制一份  bitmap_blur = Bitmap.createBitmap(bitmap_original.getWidth(),      bitmap_original.getHeight(), bitmap_original.getConfig());  createBlureScript();  setSeekBarListening();//为SeekBar设置拖拽监听}/** * Helper to load Bitmap from resource */private Bitmap loadBitmap(int resource) {  final BitmapFactory.Options options = new BitmapFactory.Options();  options.inPreferredConfig = Bitmap.Config.ARGB_8888;  return BitmapFactory.decodeResource(getResources(), resource, options);}/** * 创建Script */private void createBlureScript() {  mRS = RenderScript.create(this);  mInAllocation = Allocation.createFromBitmap(mRS, bitmap_original);  mOutAllocation = Allocation.createFromBitmap(mRS, bitmap_blur);  /*   * Create intrinsics. RenderScript has built-in features such as blur,   * convolve filter etc. These intrinsics are handy for specific   * operations without writing RenderScript kernel. In the sample, it's   * creating blur, convolve and matrix intrinsics.   */  mScriptBlur = ScriptIntrinsicBlur.create(mRS, Element.U8_4(mRS));}

private void performFilter(Allocation inAllocation,      Allocation outAllocation, Bitmap bitmapOut, float value) {  /*   * 设置模糊程度。范围在0~25之间。否则会出错   */  mScriptBlur.setRadius(value);  /*   * Invoke filter kernel   */  mScriptBlur.setInput(inAllocation);  mScriptBlur.forEach(outAllocation);  outAllocation.copyTo(bitmapOut);}

// Request UI updateimg_blur.setImageBitmap(bitmap_blur);img_blur.invalidate();

mRS = RenderScript.create(this);mScriptBlur = ScriptIntrinsicBlur.create(mRS, Element.U8_4(mRS));//RenderScript的输入和输出参数对象mInAllocation = Allocation.createFromBitmap(mRS, bitmap_original);mOutAllocation = Allocation.createFromBitmap(mRS, bitmap_blur);

/* * 设置模糊程度。范围在0~25之间。否则会出错（这个也可以只设置一次） */mScriptBlur.setRadius(value);/* * Invoke filter kernel */mScriptBlur.setInput(inAllocation);mScriptBlur.forEach(outAllocation);//将结果拷贝出来，拷贝到bitmapOut对象中outAllocation.copyTo(bitmapOut);

mRS.destory();mRs = null; 

public class MainActivity extends Activity {  private SeekBar blurSeekBar;  private ImageView img_blur;  private Bitmap bitmap_original, bitmap_blur;  private RenderScriptTask mLatestTask = null;  private RenderScript mRS;  private Allocation mInAllocation;  private Allocation mOutAllocation;  private ScriptIntrinsicBlur mScriptBlur;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    blurSeekBar = (SeekBar) findViewById(R.id.aty_main_seekBar);    img_blur = (ImageView) findViewById(R.id.aty_main_img_blur);    bitmap_original = loadBitmap(R.drawable.meet_entry_guide_3);    // 复制一份    bitmap_blur = Bitmap.createBitmap(bitmap_original.getWidth(),        bitmap_original.getHeight(), bitmap_original.getConfig());    createBlureScript();    setSeekBarListening();  }  /**   * 设置SeekBar的监听   */  private void setSeekBarListening() {    blurSeekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {      @Override      public void onStopTrackingTouch(SeekBar seekBar) {      }      @Override      public void onStartTrackingTouch(SeekBar seekBar) {      }      @Override      public void onProgressChanged(SeekBar seekBar, int progress,          boolean fromUser) {        updateImage(progress);      }    });  }  /**   * 创建Script   */  private void createBlureScript() {    mRS = RenderScript.create(this);    mInAllocation = Allocation.createFromBitmap(mRS, bitmap_original);    mOutAllocation = Allocation.createFromBitmap(mRS, bitmap_blur);    /*     * Create intrinsics. RenderScript has built-in features such as blur,     * convolve filter etc. These intrinsics are handy for specific     * operations without writing RenderScript kernel. In the sample, it's     * creating blur, convolve and matrix intrinsics.     */    mScriptBlur = ScriptIntrinsicBlur.create(mRS, Element.U8_4(mRS));  }  private void performFilter(Allocation inAllocation,      Allocation outAllocation, Bitmap bitmapOut, float value) {    /*     * Set blur kernel size     */    mScriptBlur.setRadius(value);    /*     * Invoke filter kernel     */    mScriptBlur.setInput(inAllocation);    mScriptBlur.forEach(outAllocation);    outAllocation.copyTo(bitmapOut);  }  /*   * In the AsyncTask, it invokes RenderScript intrinsics to do a filtering.   * After the filtering is done, an operation blocks at Allication.copyTo()   * in AsyncTask thread. Once all operation is finished at onPostExecute() in   * UI thread, it can invalidate and update ImageView UI.   */  private class RenderScriptTask extends AsyncTask<Float, Integer, Integer> {    Boolean issued = false;    protected Integer doInBackground(Float... values) {      if (isCancelled() == false) {        issued = true;        performFilter(mInAllocation, mOutAllocation, bitmap_blur,            values[0]);      }      return 0;    }    void updateView(Integer result) {      // Request UI update      img_blur.setImageBitmap(bitmap_blur);      img_blur.invalidate();    }    protected void onPostExecute(Integer result) {      updateView(result);    }    protected void onCancelled(Integer result) {      if (issued) {        updateView(result);      }    }  }  /*   * Invoke AsynchTask and cancel previous task. When AsyncTasks are piled up   * (typically in slow device with heavy kernel), Only the latest (and   * already started) task invokes RenderScript operation.   */  private void updateImage(int progress) {    float f = getBlureParam(progress);    if (mLatestTask != null)      mLatestTask.cancel(false);    mLatestTask = new RenderScriptTask();    mLatestTask.execute(f);  }  /**   * 模糊的值在1 ~ 25之间   *    * @param progress   *      SeekBar的进度值(0 ~ 100)   * @return 模糊值   */  private float getBlureParam(int progress) {    final float max = 25.0f;    final float min = 1.f;    return (float) ((max - min) * (progress / 100.0) + min);  }  /**   * Helper to load Bitmap from resource   */  private Bitmap loadBitmap(int resource) {    final BitmapFactory.Options options = new BitmapFactory.Options();    options.inPreferredConfig = Bitmap.Config.ARGB_8888;    return BitmapFactory.decodeResource(getResources(), resource, options);  }}