Wizzer's Blog

public void transImage(String fromFile, String toFile, int width, int height, int quality)
    {
        try
        {
            Bitmap bitmap = BitmapFactory.decodeFile(fromFile);
            int bitmapWidth = bitmap.getWidth();
            int bitmapHeight = bitmap.getHeight();
            // 缩放图片的尺寸
            float scaleWidth = (float) width / bitmapWidth;
            float scaleHeight = (float) height / bitmapHeight; 
            Matrix matrix = new Matrix();
            matrix.postScale(scaleWidth, scaleHeight);
            // 产生缩放后的Bitmap对象
            Bitmap resizeBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmapWidth, bitmapHeight, matrix, false);
            // save file
            File myCaptureFile = new File(toFile);
            FileOutputStream out = new FileOutputStream(myCaptureFile);
            if(resizeBitmap.compress(Bitmap.CompressFormat.JPEG, quality, out)){
                out.flush();
                out.close();
            }
            if(!bitmap.isRecycled()){
                bitmap.recycle();//记得释放资源，否则会内存溢出
            }
            if(!resizeBitmap.isRecycled()){
                resizeBitmap.recycle();
            }

        }
        catch (FileNotFoundException e)
        {
            e.printStackTrace();
        }
        catch (IOException ex)
        {
            ex.printStackTrace();
        }
    }