Android：使用 Google Vision API 在面部绘制地标

问题描述

我有当前的代码，可以在实时相机预览中围绕用户的脸部绘制一个边界框。

我还尝试在实时相机预览中绘制面部标志的位置。由于没有比例值，它绘制了它们但不在正确的位置

我在网上找到了这段代码，但我很难计算这个比例值，因为它是实时相机预览而不是位图图像

网上找到的示例代码

 double scale = Math.min( viewWidth / imageWidth,viewHeight / imageHeight );

 for (Landmark landmark : face.getLandmarks()) {
        int cx = (int) (landmark.getPosition().x * scale);
        int cy = (int) (landmark.getPosition().y * scale);
        canvas.drawCircle(cx,cy,10,paint);
    }

我的功能

@Override
   public void draw(Canvas canvas) {
       Face face = mFace;

       if (face == null) {
           return;
       }


       // Draws a circle at the position of the detected face,with the face's track id below.

    
       float x = translateX(face.getPosition().x + face.getWidth() / 2);
       float y = translateY(face.getPosition().y + face.getHeight() / 2);
       canvas.drawCircle(x,y,FACE_POSITION_RADIUS,mFacePositionPaint);
      


       // Draws a bounding box around the face.
       float xOffset = scaleX(face.getWidth() / 2.0f);
       float yOffset = scaleY(face.getHeight() / 2.0f);
       float left = x - xOffset;
       float top = y - yOffset;
       float right = x + xOffset;
       float bottom = y + yOffset;
       canvas.drawRect(left,top,right,bottom,mBoxPaint);

       Paint paint = new Paint();
       paint.setColor( Color.GREEN );
       paint.setStyle( Paint.Style.STROKE );
       paint.setStrokeWidth( 5 );

       for ( Landmark landmark : face.getLandmarks() ) {
           int cx = (int) ( landmark.getPosition().x);
           int cy = (int) ( landmark.getPosition().y);
           canvas.drawCircle( cx,paint );
       }

       }

解决方法

通过以下方法解决，但不完全准确

 if ((contains(face.getLandmarks(),11) != 99)
                && (contains(face.getLandmarks(),5) != 99)
                && (contains(face.getLandmarks(),6) != 99)
        ) {

            Log.i(TAG,"draw: Mouth Open >> found all the points");

            /**
             * for bottom mouth
             */
            int cBottomMouthX;
            int cBottomMouthY;

                cBottomMouthX = (int) translateX(face.getLandmarks().get(contains(face.getLandmarks(),0)).getPosition().x);
                cBottomMouthY = (int) translateY(face.getLandmarks().get(contains(face.getLandmarks(),0)).getPosition().y);

                Log.i(TAG,"draw: Condition Bottom mouth >> cBottomMouthX >> " + cBottomMouthX + "    cBottomMouthY >> " + cBottomMouthY);

            canvas.drawCircle(cBottomMouthX,cBottomMouthY,10,paint);

            /**
             * for left mouth
             */
            int cLeftMouthX;
            int cLeftMouthY;

                cLeftMouthX = (int) translateX(face.getLandmarks().get(contains(face.getLandmarks(),5)).getPosition().x);
                cLeftMouthY = (int) translateY(face.getLandmarks().get(contains(face.getLandmarks(),5)).getPosition().y);

                Log.i(TAG,"draw: Condition LEft mouth >> cLeftMouthX >> " + cLeftMouthX + "    cLeftMouthY >> " + cLeftMouthY);
                cLeftMouthX = (int) translateX(face.getLandmarks().get(contains(face.getLandmarks(),5)).getPosition().y);
            canvas.drawCircle(cLeftMouthX,cLeftMouthY,paint);

            /**
             * for Right mouth
             */
            int cRightMouthX;
            int cRightMouthY;

                cRightMouthX = (int) translateX(face.getLandmarks().get(contains(face.getLandmarks(),11)).getPosition().x);
                cRightMouthY = (int) translateY(face.getLandmarks().get(contains(face.getLandmarks(),11)).getPosition().y);

                Log.i(TAG,"draw: Condition Right mouth >> cRightMouthX >> " + cRightMouthX + "    cRightMouthY >> " + cRightMouthY);



                cRightMouthX = (int) translateX(face.getLandmarks().get(contains(face.getLandmarks(),11)).getPosition().y);

            canvas.drawCircle(cRightMouthX,cRightMouthY,paint);

            float centerPointX = (cLeftMouthX + cRightMouthX) / 2;
            float centerPointY = ((cLeftMouthY + cRightMouthY) / 2) - 20;

            canvas.drawCircle(centerPointX,centerPointY,paint);

            float differenceX = centerPointX - cBottomMouthX;
            float differenceY = centerPointY - cBottomMouthY;

            Log.i(TAG,"draw: difference X >> " + differenceX + "     Y >> " + differenceY);

            if (differenceY < (-60)) {
                Log.i(TAG,"draw: difference - Mouth is OPENED ");
            } else {
                Log.i(TAG,"draw: difference - Mouth is CLOSED ");
            }
        }
    }


    private int contains (List < Landmark > list,int name){
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).getType() == name) {
                return i;
            }
        }
        return 99;
    }