Bitmap缩放相关

Bitmap bitmap =null;
//通过工厂类，解释路径，获得图片
bitmap = BitmapFactory.decodeFile(filePath); 
//get width & height  
    	int width = bitmap.getWidth(); 
    	int height = bitmap.getHeight(); 
Bitmap destBitmap = null;
//destination height & width
    	float destH = height;
    	float destW = width;
    	//Scale new/old
    	float temp1 =  0; 
    	float temp2 =  0; 
    	
    	//compress height below 1024
    	if (height > 1024) {
		    destH = 1024;
		    temp1 =  ((float) destH) / ((float) height); 
		    destW = width * temp1;
		     if (destW > 1024) {
		    	 temp1 =  ((float) 1024) / ((float) destW); 
		    	 destW = 1024;
		    	 destH = destH * temp1;
			}
		}else{
			if (width > 1024) {
				destW = 1024;
				temp2 =  ((float) destW) / ((float) width);
				destH = height * temp2;
				
			}
		}

        try {
//Creates a new bitmap, scaled from an existing bitmap, when possible
        	destBitmap = Bitmap.createScaledBitmap(bitmap, (int) destW, (int)destH, true);
        	destBitmap = switchColor(destBitmap);
//save new bitmap
        	OutputStream outStream = null;
        	outStream = new FileOutputStream(new File(filePath));
//Write a compressed version of the bitmap to the specified outputstream.
        	destBitmap.compress(Bitmap.CompressFormat.JPEG, 100, outStream);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}