拍照并转换为Base64

Question

我使用下面的代码用相机拍照。我不想保存，而是想将它编码为 Base64 然后将它作为输入传递给另一个 API。我看不到方法，如何修改代码以在 Base64 而不是常规文件中拍照。

 public class CameraDemoActivity extends Activity {
    int TAKE_PHOTO_CODE = 0;
    public static int count = 0;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final String dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/picFolder/";
        File newdir = new File(dir);
        newdir.mkdirs();

        Button capture = (Button) findViewById(R.id.btnCapture);
        capture.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                count++;
                String file = dir+count+".jpg";
                File newfile = new File(file);
                try {
                    newfile.createNewFile();
                }
                catch (IOException e)
                {
                }

                Uri outputFileUri = Uri.fromFile(newfile);

                Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);

                startActivityForResult(cameraIntent, TAKE_PHOTO_CODE);
            }
        });
    }

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

        if (requestCode == TAKE_PHOTO_CODE && resultCode == RESULT_OK) {
            Log.d("CameraDemo", "Pic saved");
        }
    }
}

我尝试使用下面的代码将图像转换为 Base64 。

 public static String encodeToBase64(Bitmap image, Bitmap.CompressFormat compressFormat, int quality)
{
    ByteArrayOutputStream byteArrayOS = new ByteArrayOutputStream();
    image.compress(compressFormat, quality, byteArrayOS);
    return Base64.encodeToString(byteArrayOS.toByteArray(), Base64.DEFAULT);
}

上面描述的应该是比保存图像然后寻找图像对其进行编码更直接和更容易的方法。

原文由 plaidshirt 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

试试这个：

ImageUri 到位图：

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

            if (requestCode == TAKE_PHOTO_CODE && resultCode == RESULT_OK) {
                final Uri imageUri = data.getData();
                final InputStream imageStream = getContentResolver().openInputStream(imageUri);
                final Bitmap selectedImage = BitmapFactory.decodeStream(imageStream);
                String encodedImage = encodeImage(selectedImage);
            }
        }

在 base64 中编码位图

   private String encodeImage(Bitmap bm)
    {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG,100,baos);
        byte[] b = baos.toByteArray();
        String encImage = Base64.encodeToString(b, Base64.DEFAULT);

        return encImage;
    }

从 FilePath 编码为 base64

  private String encodeImage(String path)
    {
        File imagefile = new File(path);
        FileInputStream fis = null;
        try{
            fis = new FileInputStream(imagefile);
        }catch(FileNotFoundException e){
            e.printStackTrace();
        }
        Bitmap bm = BitmapFactory.decodeStream(fis);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG,100,baos);
        byte[] b = baos.toByteArray();
        String encImage = Base64.encodeToString(b, Base64.DEFAULT);
        //Base64.de
        return encImage;

    }

输出：

原文由 Fabio Venturi Pastor 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

我这样写我的代码：

 public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Camera mCamera = Camera.open();
        mCamera.startPreview();// I don't know why I added that,
                               // but without it doesn't work... :D

        mCamera.takePicture(null, null, mPicture);
    }

    private Camera.PictureCallback mPicture = new Camera.PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            System.out.println("***************");
            System.out.println(Base64.encodeToString(data, Base64.DEFAULT));
            System.out.println("***************");
        }
    };
}

它完美地工作……

原文由 LetsGoBrandon 发布，翻译遵循 CC BY-SA 3.0 许可协议