Question

我们正在构建一个应用程序，它从库中选择一个图像，在imageView中显示它。当按下加密按钮时，它被传递给java类，在那里它被加密并存储在内存中。我想在加密前压缩图像。我正在使用Bitmap.scaledimage，但我不确切知道在哪里添加它

挑选图片的代码：

  public void onClick(View v)
    {
        Intent i= new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(i,SELECTED_PICTURE);
    }
    });

显示图片的代码：

 protected void onActivityResult(int requestCode,int resultCode,Intent data)
{
    super.onActivityResult(requestCode, resultCode, data);
    switch(requestCode)
    {
    case SELECTED_PICTURE:
        if(resultCode==RESULT_OK)
        {

            Uri uri= data.getData();
            String[]projection= {MediaStore.Images.Media.DATA};                                                                   
            Cursor cursor= getContentResolver().query(uri, projection, null, null, null);
            cursor.moveToFirst();
            int columnIndex= cursor.getColumnIndex(projection[0]);
            filePath= cursor.getString(columnIndex);
            cursor.close();
            iv.setImageBitmap(BitmapFactory.decodeFile(filePath));
            }
        break;

加密代码：

one = (Button) findViewById(R.id.button2);
    one.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
            try{
                blowfish encryptFile = new blowfish("thisismypassword");
                //destpath=Environment.getExternalStorageDirectory().getAbsolutePath()+nameoffolder;
                destpath= x.getPath()+nameoffolder;
                //destpath="/storage/sdcard/test";
                encryptFile.encrypt(filePath,destpath);
                Toast.makeText(Image.this,
                        "Done encrypting..yey..",
                        Toast.LENGTH_SHORT).show();

                }catch (Exception e) {
                    Toast.makeText(Image.this, e.getMessage(),
                            Toast.LENGTH_SHORT).show();System.out.println("sells");
            }
        }
    });

文件x声明如下：

final File x=new File(android.os.Environment.getExternalStorageDirectory(),File.separator+"Image");
    x.mkdirs();

FilePath是字符串。

我想知道在哪里可以添加图像压缩（代码的哪一部分）。图像压缩我们需要位图，但在整个过程中我正在使用uri，文件和字符串进行存储和显示。

Answer 1

public Bitmap decodeSampledBitmapFromUri(String uri, int reqWidth, int reqHeight) {

    Bitmap bm = null;

    try{
        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(getContentResolver().openInputStream(Uri.parse(uri)), null, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bm = BitmapFactory.decodeStream(getContentResolver().openInputStream(Uri.parse(uri)), null, options);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
        Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_LONG).show();
    }

    return bm;
}

public int calculateInSampleSize(
        BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {
        if (width > height) {
            inSampleSize = Math.round((float)height / (float)reqHeight);
        } else {
            inSampleSize = Math.round((float)width / (float)reqWidth);
        }
    }
    return inSampleSize;
}

可能是这样的。我可以看到你的完整编码吗？我需要你的加密和解密部分。

需要在Android中传递压缩图像以进行加密

1 个答案: