android 处理图片资源

android在处理一写图片资源的时候，会进行一些类型的转换，现在有空整理一下：

1、Drawable → Bitmap

Java代码

public static Bitmap drawableToBitmap(Drawable drawable) {  

        Bitmap bitmap = Bitmap  

                        .createBitmap(  

                                        drawable.getIntrinsicWidth(),  

                                        drawable.getIntrinsicHeight(),  

                                        drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888  

                                                        : Bitmap.Config.RGB_565);  

        Canvas canvas = new Canvas(bitmap);  

//canvas.setBitmap(bitmap);

        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());  

        drawable.draw(canvas);  

return bitmap;  

} 

public static Bitmap drawableToBitmap(Drawable drawable) {

Bitmap bitmap = Bitmap
.createBitmap(
drawable.getIntrinsicWidth(),
drawable.getIntrinsicHeight(),
drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
: Bitmap.Config.RGB_565);
Canvas canvas = new Canvas(bitmap);
//canvas.setBitmap(bitmap);
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
drawable.draw(canvas);
return bitmap;
}

2、从资源中获取Bitmap

Java代码

Resources res=getResources();  

Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic); 

Resources res=getResources();

Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic);

3、Bitmap → byte[]

Java代码

private byte[] Bitmap2Bytes(Bitmap bm){  

    ByteArrayOutputStream baos = new ByteArrayOutputStream();    

    bm.compress(Bitmap.CompressFormat.PNG, 100, baos);    

return baos.toByteArray();  

   } 

private byte[] Bitmap2Bytes(Bitmap bm){     ByteArrayOutputStream baos = new ByteArrayOutputStream();      bm.compress(Bitmap.CompressFormat.PNG, 100, baos);      return baos.toByteArray();    }

4、 byte[] → Bitmap

Java代码

private Bitmap Bytes2Bimap(byte[] b){  

if(b.length!=0){  

return BitmapFactory.decodeByteArray(b, 0, b.length);  

            }  

else {  

return null;  

            }  

      } 

private Bitmap Bytes2Bimap(byte[] b){
if(b.length!=0){
return BitmapFactory.decodeByteArray(b, 0, b.length);
}
else {
return null;
}
}

以上是我在实践中遇到的一些转换，以后遇到类似的就不用到处找了，希望对大家也有一点用处！