android bitmap縮放

package com.dengfan;

import android.graphics.Bitmap;

import android.graphics.Matrix;

public class BitmapZoom 

{

public static Bitmap bitmapZoomByPercent(Bitmap srcBitmap ,double percent)

{

int srcWidth = srcBitmap.getWidth();   

        int srcHeight = srcBitmap.getHeight();    

        float scaleWidth = (float) percent;   

        float scaleHeight = (float) percent;   

        return bitmapZoomByScale(srcBitmap, scaleWidth, scaleHeight);

}

public static Bitmap bitmapZoomBySize(Bitmap srcBitmap,int newWidth,int newHeight)

{

int srcWidth = srcBitmap.getWidth();   

        int srcHeight = srcBitmap.getHeight();    

        float scaleWidth = ((float) newWidth) / srcWidth;   

        float scaleHeight = ((float) newHeight) / srcHeight;   

        return bitmapZoomByScale(srcBitmap, scaleWidth, scaleHeight);

}

public static Bitmap bitmapZoomByHeight(Bitmap srcBitmap,int newHeight)

{

int srcWidth = srcBitmap.getWidth();   

        int srcHeight = srcBitmap.getHeight();    

        float scaleHeight = ((float) newHeight) / srcHeight;   

        float scaleWidth = scaleHeight;

        return bitmapZoomByScale(srcBitmap, scaleWidth, scaleHeight);

}

public static Bitmap bitmapZoomByWidth(Bitmap srcBitmap,int newWidth)

{

int srcWidth = srcBitmap.getWidth();   

        int srcHeight = srcBitmap.getHeight();    

        float scaleWidth = ((float) newWidth) / srcWidth;   

        float scaleHeight = scaleWidth;

        return bitmapZoomByScale(srcBitmap, scaleWidth, scaleHeight);

}

public static Bitmap bitmapZoomByScale(Bitmap srcBitmap,float scaleWidth,float scaleHeight)

{

int srcWidth = srcBitmap.getWidth();   

        int srcHeight = srcBitmap.getHeight();  

Matrix matrix = new Matrix();   

        matrix.postScale(scaleWidth, scaleHeight);     

        Bitmap resizedBitmap = Bitmap.createBitmap(srcBitmap, 0, 0, srcWidth,   

        srcHeight, matrix, true);

        if(resizedBitmap != null)

        {

        return resizedBitmap;

        }

        else

        {

        return srcBitmap;

        }

}

}