View.post不能加快图像处理速度吗?

| 我正在尝试通过对应用程序进行线程化来加快速度。它是一款将鱼眼效果置于位图上的应用程序。它运行良好,但运行缓慢。我已经注销了各种方法的一些处理时间,并已将其精确定位到过滤器类中的bucket()方法。此方法需要一个位图并循环遍历它,从而使像素失真,此循环大约需要40秒才能完成!我已经尝试过AsyncTask,但这也需要40秒钟以上的时间。最后,我尝试了View.post机制,但这产生了相同的结果。有什么办法可以加快这个应用程序的速度吗?任何想法将不胜感激,谢谢马特。 。
public class TouchView extends View{


    private File tempFile;
    private byte[] imageArray;
    private Bitmap bgr;
    private Bitmap bm;
    private Bitmap bgr2 = null;;
    private Paint pTouch;
    private int centreX = 1;
    private int centreY = 1;
    private int radius = 50;
    private int Progress = 1;
    private static final String TAG = \"*********TouchView\";
    private Filters f = null;
    private boolean AsyncRunning = false;
   // private MyTask mt = null;



    public TouchView(Context context) {
        super(context);
       // TouchView(context, null);
    }




    public TouchView(Context context, AttributeSet attr) {
        super(context,attr);


       ........... code to get bitmap from camera shot.........

        bgr2 = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());



       f = new Filters();





    }// end of touchView constructor


    public void findCirclePixels(){ 


              new Thread(new Runnable() {
                public void run() {
                    float prog = (float)Progress/150000;

                final Bitmap bgr3 = f.barrel(bgr,prog);
                  TouchView.this.post(new Runnable() {
                    public void run() {
                      TouchView.this.bgr2 = bgr3;
                      TouchView.this.invalidate();
                    }
                  });
                }
              }).start();





        }// end of changePixel()








    public void initSlider(final HorizontalSlider slider)
    {
      //  Log.e(TAG, \"******setting up slider*********** \");
        slider.setOnProgressChangeListener(changeListener);
    }



    private OnProgressChangeListener changeListener = new OnProgressChangeListener() {


        @Override
        public void onProgressChanged(View v, int progress) {
            // TODO Auto-generated method stub


              setProgress(progress);
            //TouchView.this.Progress = progress;


        }
    };



    @Override
    public void onDraw(Canvas canvas){
        super.onDraw(canvas);


        canvas.drawBitmap(bgr2, 0, 0, null);




    }//end of onDraw




    protected void setProgress(int progress2) {
        //Log.e(TAG, \"***********in SETPROGRESS\");
        this.Progress = progress2;



        findCirclePixels();
        invalidate();


    }




}
import android.graphics.Bitmap;
import android.util.Log;

class Filters{
    float xscale;
    float yscale;
    float xshift;
    float yshift;
    int [] s;
    private String TAG = \"Filters\";
    long getRadXStart = 0;
    long getRadXEnd = 0;
    long startSample = 0;
    long endSample = 0;
    public Filters(){

        Log.e(TAG, \"***********inside filter constructor\");
    }

    public Bitmap barrel (Bitmap input, float k){
        //Log.e(TAG, \"***********INSIDE BARREL METHOD \");

        float centerX=input.getWidth()/2; //center of distortion
        float centerY=input.getHeight()/2;

        int width = input.getWidth(); //image bounds
        int height = input.getHeight();

        Bitmap dst = Bitmap.createBitmap(width, height,input.getConfig() ); //output pic
       // Log.e(TAG, \"***********dst bitmap created \");
          xshift = calc_shift(0,centerX-1,centerX,k);

          float newcenterX = width-centerX;
          float xshift_2 = calc_shift(0,newcenterX-1,newcenterX,k);

          yshift = calc_shift(0,centerY-1,centerY,k);

          float newcenterY = height-centerY;
          float yshift_2 = calc_shift(0,newcenterY-1,newcenterY,k);

          xscale = (width-xshift-xshift_2)/width;
        //  Log.e(TAG, \"***********xscale =\"+xscale);
          yscale = (height-yshift-yshift_2)/height;
        //  Log.e(TAG, \"***********yscale =\"+yscale);
        //  Log.e(TAG, \"***********filter.barrel() about to loop through bm\");
          /*for(int j=0;j<dst.getHeight();j++){
              for(int i=0;i<dst.getWidth();i++){
                float x = getRadialX((float)i,(float)j,centerX,centerY,k);
                float y = getRadialY((float)i,(float)j,centerX,centerY,k);
                sampleImage(input,x,y);
                int color = ((s[1]&0x0ff)<<16)|((s[2]&0x0ff)<<8)|(s[3]&0x0ff);
    //            System.out.print(i+\" \"+j+\" \\\\\");

                dst.setPixel(i, j, color);

              }
            }*/

          int origPixel;
          long startLoop = System.currentTimeMillis();
          for(int j=0;j<dst.getHeight();j++){
              for(int i=0;i<dst.getWidth();i++){
                 origPixel= input.getPixel(i,j);
                 getRadXStart = System.currentTimeMillis();
                float x = getRadialX((float)j,(float)i,centerX,centerY,k);
                getRadXEnd= System.currentTimeMillis();

                float y = getRadialY((float)j,(float)i,centerX,centerY,k);

                sampleImage(input,x,y);

                int color = ((s[1]&0x0ff)<<16)|((s[2]&0x0ff)<<8)|(s[3]&0x0ff);
    //            System.out.print(i+\" \"+j+\" \\\\\");

                if( Math.sqrt( Math.pow(i - centerX, 2) + ( Math.pow(j - centerY, 2) ) ) <= 150 ){
                dst.setPixel(i, j, color);
                }else{
                    dst.setPixel(i,j,origPixel);
                }
              }
            }
          long endLoop = System.currentTimeMillis();
          long loopDuration = endLoop - startLoop;
          long radXDuration = getRadXEnd - getRadXStart;
          long sampleDur = endSample - startSample;

          Log.e(TAG, \"sample method took \"+sampleDur+\"ms\");
          Log.e(TAG, \"getRadialX took \"+radXDuration+\"ms\");
          Log.e(TAG, \"loop took \"+loopDuration+\"ms\");

        //  Log.e(TAG, \"***********filter.barrel()  looped through bm about to return dst bm\");
        return dst;
    }

    void sampleImage(Bitmap arr, float idx0, float idx1)
    {
         startSample = System.currentTimeMillis();
        s = new int [4];
      if(idx0<0 || idx1<0 || idx0>(arr.getHeight()-1) || idx1>(arr.getWidth()-1)){
        s[0]=0;
        s[1]=0;
        s[2]=0;
        s[3]=0;
        return;
      }

      float idx0_fl=(float) Math.floor(idx0);
      float idx0_cl=(float) Math.ceil(idx0);
      float idx1_fl=(float) Math.floor(idx1);
      float idx1_cl=(float) Math.ceil(idx1);

      int [] s1 = getARGB(arr,(int)idx0_fl,(int)idx1_fl);
      int [] s2 = getARGB(arr,(int)idx0_fl,(int)idx1_cl);
      int [] s3 = getARGB(arr,(int)idx0_cl,(int)idx1_cl);
      int [] s4 = getARGB(arr,(int)idx0_cl,(int)idx1_fl);

      float x = idx0 - idx0_fl;
      float y = idx1 - idx1_fl;

      s[0]= (int) (s1[0]*(1-x)*(1-y) + s2[0]*(1-x)*y + s3[0]*x*y + s4[0]*x*(1-y));
      s[1]= (int) (s1[1]*(1-x)*(1-y) + s2[1]*(1-x)*y + s3[1]*x*y + s4[1]*x*(1-y));
      s[2]= (int) (s1[2]*(1-x)*(1-y) + s2[2]*(1-x)*y + s3[2]*x*y + s4[2]*x*(1-y));
      s[3]= (int) (s1[3]*(1-x)*(1-y) + s2[3]*(1-x)*y + s3[3]*x*y + s4[3]*x*(1-y));

      endSample = System.currentTimeMillis();
    }

    int [] getARGB(Bitmap buf,int x, int y){

        int rgb = buf.getPixel(y, x); // Returns by default ARGB.
        int [] scalar = new int[4];
        scalar[0] = (rgb >>> 24) & 0xFF;
        scalar[1] = (rgb >>> 16) & 0xFF;
        scalar[2] = (rgb >>> 8) & 0xFF;
        scalar[3] = (rgb >>> 0) & 0xFF;
        return scalar;
    }

    float getRadialX(float x,float y,float cx,float cy,float k){

      x = (x*xscale+xshift);
      y = (y*yscale+yshift);
      float res = x+((x-cx)*k*((x-cx)*(x-cx)+(y-cy)*(y-cy)));
      return res;
    }

    float getRadialY(float x,float y,float cx,float cy,float k){

      x = (x*xscale+xshift);
      y = (y*yscale+yshift);
      float res = y+((y-cy)*k*((x-cx)*(x-cx)+(y-cy)*(y-cy)));
      return res;
    }

    float thresh = 1;

    float calc_shift(float x1,float x2,float cx,float k){

      float x3 = (float)(x1+(x2-x1)*0.5);
      float res1 = x1+((x1-cx)*k*((x1-cx)*(x1-cx)));
      float res3 = x3+((x3-cx)*k*((x3-cx)*(x3-cx)));

      if(res1>-thresh && res1 < thresh)
        return x1;
      if(res3<0){
        return calc_shift(x3,x2,cx,k);
      }
      else{
        return calc_shift(x1,x3,cx,k);
      }
    }



}// end of filters class
    
已邀请:
        浮点数学通常在几乎所创建的每台计算机上都很糟糕。但是,对于缺乏浮点协处理器支持的设备,例如一半的Android设备,它确实很糟糕。因此,摆脱浮点数学的每一点,例如: 您不需要通过浮点
ceil()
floor()
方法运行整数 您无需计算
sqrt()
即可与
150
进行比较,而无需跳过
sqrt()
并与
22500
进行比较 您不需要浮点数8来计算事物的平方;而是使用称为“乘法”的高级数学运算 我怀疑半像素在您的计算中是否会很重要,因此您可能不需要
centerX
centerY
作为
float
值 等等 一时之间,您可能需要使用一些技巧,例如适用于Android的Google Maps插件。通常,您会想到以十进制表示的纬度和经度,但这意味着很多浮点数学运算。 Google Maps使用微度(10 ^ 6倍)的经度和纬度,以便能够以定点数学进行所有计算,同时保持合理的准确性。 我不能说这是否会使性能降低到您认为合理的程度。但是,在开始抱怨Android代码的质量之前,您应该确保您的代码质量合理,就像在上一次评论中所做的那样。     

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