1. 技术文章
  2. Taking a picture via camera and sending it to server in bytearray

Taking a picture via camera and sending it to server in bytearray

由 梦想与她 提交于 2019-11-29 13:03:26

If you use Bundle extras = data.getExtras(); in your onActivityResult() then it will return thumbnail image not actual image.

Here is code I have used for Capturing and Saving Camera Image then display it to ImageView. You can use according to your need.

You have to save Camera image to specific location then fetch from that location then convert it to byte-array.

Here is method for opening capturing camera image activity.

private static final int CAMERA_PHOTO = 111;
private Uri imageToUploadUri;

private void captureCameraImage() {
        Intent chooserIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        File f = new File(Environment.getExternalStorageDirectory(), "POST_IMAGE.jpg");
        chooserIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
        imageToUploadUri = Uri.fromFile(f);
        startActivityForResult(chooserIntent, CAMERA_PHOTO);
    }

then your onActivityResult() method should be like this.

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

            if (requestCode == CAMERA_PHOTO && resultCode == Activity.RESULT_OK) {
                if(imageToUploadUri != null){
                    Uri selectedImage = imageToUploadUri;
                    getContentResolver().notifyChange(selectedImage, null);
                    Bitmap reducedSizeBitmap = getBitmap(imageToUploadUri.getPath());
                    if(reducedSizeBitmap != null){
                        ImgPhoto.setImageBitmap(reducedSizeBitmap);
                        Button uploadImageButton = (Button) findViewById(R.id.uploadUserImageButton);
                          uploadImageButton.setVisibility(View.VISIBLE);                
                    }else{
                        Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
                    }
                }else{
                    Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
                }
            } 
        }

Here is getBitmap() method used in onActivityResult(). I have done all performance improvement that can be possible while getting camera capture image bitmap.

private Bitmap getBitmap(String path) {

        Uri uri = Uri.fromFile(new File(path));
        InputStream in = null;
        try {
            final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
            in = getContentResolver().openInputStream(uri);

            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(in, null, o);
            in.close();


            int scale = 1;
            while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) >
                    IMAGE_MAX_SIZE) {
                scale++;
            }
            Log.d("", "scale = " + scale + ", orig-width: " + o.outWidth + ", orig-height: " + o.outHeight);

            Bitmap b = null;
            in = getContentResolver().openInputStream(uri);
            if (scale > 1) {
                scale--;
                // scale to max possible inSampleSize that still yields an image
                // larger than target
                o = new BitmapFactory.Options();
                o.inSampleSize = scale;
                b = BitmapFactory.decodeStream(in, null, o);

                // resize to desired dimensions
                int height = b.getHeight();
                int width = b.getWidth();
                Log.d("", "1th scale operation dimenions - width: " + width + ", height: " + height);

                double y = Math.sqrt(IMAGE_MAX_SIZE
                        / (((double) width) / height));
                double x = (y / height) * width;

                Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x,
                        (int) y, true);
                b.recycle();
                b = scaledBitmap;

                System.gc();
            } else {
                b = BitmapFactory.decodeStream(in);
            }
            in.close();

            Log.d("", "bitmap size - width: " + b.getWidth() + ", height: " +
                    b.getHeight());
            return b;
        } catch (IOException e) {
            Log.e("", e.getMessage(), e);
            return null;
        }
    }

EDIT:

Here is method for uploading image to server.

/**
 * Upload Image to server
 *
 * @param file              image to be saved
 * @param compressorQuality quality of image
 * @return path of uploaded image in server
 */
private String uploadImage(Bitmap file, int compressorQuality) {
    String final_upload_filename = "demo_image.png";
    String response = null;
    HttpURLConnection conn = null;
    try {
        String lineEnd = "\r\n";
        String twoHyphens = "--";
        String boundary = "---------------------------14737809831466499882746641449";
        URL url = new URL("image_upload_url");
        conn = (HttpURLConnection) url.openConnection();
        conn.setDoInput(true);
        conn.setDoOutput(true);
        conn.setUseCaches(false);
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Connection", "Keep-Alive");
        conn.setRequestProperty("ENCTYPE", "multipart/form-data");
        conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
        conn.setRequestProperty("uploaded_file", final_upload_filename);
        DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
        dos.writeBytes(lineEnd + twoHyphens + boundary + lineEnd);
        dos.writeBytes("Content-Disposition: form-data; name=\"userfile\"; filename=\"" + final_upload_filename + "\"" + lineEnd);
        dos.writeBytes("Content-Type: application/octet-stream" + lineEnd);
        dos.writeBytes(lineEnd);
        file.compress(CompressFormat.PNG, compressorQuality, dos);
        dos.writeBytes(lineEnd);
        dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
        dos.flush();
        dos.close();
        InputStream is = conn.getInputStream();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        int bytesRead;
        byte[] bytes = new byte[1024];
        while ((bytesRead = is.read(bytes)) != -1) {
            baos.write(bytes, 0, bytesRead);
        }
        byte[] bytesReceived = baos.toByteArray();
        baos.close();
        is.close();
        response = new String(bytesReceived);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (conn != null) {
            conn.disconnect();
        }
    }
    return response;
}

You need to make upload script in backend server to store image data in particular folder.

I hope it helps!

At first you need to create a file and save image on it and here's a code.

//method to save image in internal or external storage

private void storeImage(Bitmap image,String imageName) {
    File pictureFile = getOutputMediaFile(imageName);
    if (pictureFile == null) {
        Log.d(TAG,"Error creating media file, check storage permissions: ");// e.getMessage());
        return;
    } 
    try {
        FileOutputStream fos = new FileOutputStream(pictureFile);
        image.compress(Bitmap.CompressFormat.PNG, 90, fos);
        fos.close();
    } catch (FileNotFoundException e) {
        Log.d(TAG, "File not found: " + e.getMessage());
    } catch (IOException e) {
        Log.d(TAG, "Error accessing file: " + e.getMessage());
    }  
}

//method to create file to save image on it

private  File getOutputMediaFile(String imageName){
    //create folder with name FoursquareAPI
    File mediaStorageDir = new File(Environment.getExternalStorageDirectory()
            + "/FoursquareAPI");

    // Create the storage directory if it does not exist
    if (! mediaStorageDir.exists()){
        if (! mediaStorageDir.mkdirs()){
            return null;
        }
    } 
    File mediaFile;
        String mImageName= imageName +".png";
        mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName);  
    return mediaFile;
}
标签
java
android
Spring
android-camera
imgscalr
易学教程内所有资源均来自网络或用户发布的内容，如有违反法律规定的内容欢迎反馈！
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!