java - Android 将图库中的图像转换为 base64 导致 OutOfMemory 异常

Question

我想从图库中加载图像，然后将其转换为 base64。

这听起来并不难。所以我这样做了:

首先打开图库并选择图片:

picteureBtn.setOnClickListener(new View.OnClickListener() {
            private Uri imageUri;

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

                startActivityForResult(i, RESULT_LOAD_IMAGE);

            }
        });

第二个 onActivityResult:

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };

            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            picturePath = cursor.getString(columnIndex);
            cursor.close();


        }


    }

最后，我想解码位于 picutrePath 的 image

                String b64;
                StringEntity se;
                String entityContents="";
                if (!picturePath.equals("")){
                    Bitmap bm = BitmapFactory.decodeFile(picturePath);
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();  
                    bm.compress(Bitmap.CompressFormat.JPEG, 100, baos);

                    byte[] b = baos.toByteArray(); 
                    b64=Base64.encodeToString(b, Base64.DEFAULT);
                }

不幸的是我得到:

06-24 16:38:14.296: E/AndroidRuntime(3538): FATAL EXCEPTION: main
06-24 16:38:14.296: E/AndroidRuntime(3538): java.lang.OutOfMemoryError
06-24 16:38:14.296: E/AndroidRuntime(3538):     at java.io.ByteArrayOutputStream.toByteArray(ByteArrayOutputStream.java:122)

谁能指出我哪里做错了？

Answer 1

我建议改变

Bitmap bm = BitmapFactory.decodeFile(picturePath);
ByteArrayOutputStream baos = new ByteArrayOutputStream();  
bm.compress(Bitmap.CompressFormat.JPEG, 100, baos);
//added lines
bm.recycle();
bm = null;   
//added lines 
byte[] b = baos.toByteArray(); 
b64=Base64.encodeToString(b, Base64.DEFAULT);

这样，您就不会将位图加载到应用内存中两次。