android - 如何将android中的高分辨率图像上传到.net API服务器？

Question

我正在使用下面的代码将图像上传到服务器，但它正在将图像压缩到较低的分辨率。

    class ImageUploadTask extends AsyncTask<String, Void, String> {

 @Override
        protected String doInBackground(String... params) {
        ByteArrayBody bab;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();   

URL url = new URL(webAddressToPost);
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();

                conn.setRequestMethod("POST");
                conn.setRequestProperty("Connection", "Keep-Alive");
                conn.setRequestProperty("enctype", "multipart/form-data");

                MultipartEntity entity = new MultipartEntity();

        signature_image.compress(Bitmap.CompressFormat.PNG, 100, bos);
        byte[] data = bos.toByteArray();
        bab = new ByteArrayBody(data, contactNo+"_Signature.png");

entity.addPart("file", bab);
conn.addRequestProperty(entity.getContentType().getName(), entity.getContentType().getValue());

OutputStream os = conn.getOutputStream();
                entity.writeTo(conn.getOutputStream());
                os.close();
                conn.connect();
}
}

如何将高分辨率图片上传到服务器而不是压缩图片？

Answer 1

您的代码将压缩图像，然后上传到服务器。而是使用以下代码将原始分辨率的图像上传到服务器。

class ImageUploadTask extends AsyncTask<String, Integer, String> {
        private String webAddressToPost = "WRITE_YOUR_API_URL_TO_UPLOAD_IMAGE";

        @Override
        protected void onPreExecute() {
        }


        @Override
        protected String doInBackground(String... params) {
            String image_file_type = params[0];
            String file_name = params[1];
            int i=1;
            if (i==1){


                int day, month, year;
                int second, minute, hour;
                GregorianCalendar date = new GregorianCalendar();

                day = date.get(Calendar.DAY_OF_MONTH);
                month = date.get(Calendar.MONTH);
                year = date.get(Calendar.YEAR);

                second = date.get(Calendar.SECOND);
                minute = date.get(Calendar.MINUTE);
                hour = date.get(Calendar.HOUR);

                String name=(hour+""+minute+""+second+""+day+""+(month+1)+""+year);
                String tag=name+".jpg";



                    fileName = frontCameraImageUrl.replace(frontCameraImageUrl,tag);
                    sourceFile = new File(frontCameraImageUrl);

                HttpURLConnection conn = null;
                DataOutputStream dos = null;
                String lineEnd = "\r\n";
                String twoHyphens = "--";
                String boundary = "*****";
                int bytesRead, bytesAvailable, bufferSize;
                byte[] buffer;
                int maxBufferSize = 1 * 1024 * 1024;


                if (!sourceFile.isFile()) {


                    Log.e("uploadFile", "Source File not exist :");


                    return "0";

                }
                else
                {
                    try {

                        // open a URL connection to the Servlet
                        FileInputStream fileInputStream = new FileInputStream(sourceFile);
                        URL url = new URL(webAddressToPost);

                        // Open a HTTP  connection to  the URL
                        conn = (HttpURLConnection) url.openConnection();
                        conn.setDoInput(true); // Allow Inputs
                        conn.setDoOutput(true); // Allow Outputs
                        conn.setUseCaches(false); // Don't use a Cached Copy
                        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", fileName);

                        dos = new DataOutputStream(conn.getOutputStream());

                        dos.writeBytes(twoHyphens + boundary + lineEnd);
                        dos.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\""
                                + file_name + "\"" + lineEnd);

                        dos.writeBytes(lineEnd);




                        // create a buffer of  maximum size
                        bytesAvailable = fileInputStream.available();

                        bufferSize = Math.min(bytesAvailable, maxBufferSize);
                        buffer = new byte[bufferSize];

                        // read file and write it into form...
                        bytesRead = fileInputStream.read(buffer, 0, bufferSize);

                        while (bytesRead > 0) {

                            dos.write(buffer, 0, bufferSize);
                            bytesAvailable = fileInputStream.available();
                            bufferSize = Math.min(bytesAvailable, maxBufferSize);
                            bytesRead = fileInputStream.read(buffer, 0, bufferSize);

                        }

                        // send multipart form data necesssary after file data...
                        dos.writeBytes(lineEnd);
                        dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);

                        // Responses from the server (code and message)
                        int serverResponseCode = conn.getResponseCode();
                        String serverResponseMessage = conn.getResponseMessage();

                        Log.i("uploadFile", "HTTP Response is : "
                                + serverResponseMessage + ": " + serverResponseCode);

                        if(serverResponseCode == 200){

                            runOnUiThread(new Runnable() {
                                public void run() {
                                    Toast.makeText(MainActivity.this, "File Upload Complete.", Toast.LENGTH_SHORT).show();
                                }
                            });
                        }

                        //close the streams //
                        fileInputStream.close();
                        dos.flush();
                        dos.close();

                    } catch (MalformedURLException ex) {

                        ex.printStackTrace();

                        runOnUiThread(new Runnable() {
                            public void run() {
                                Toast.makeText(MainActivity.this, "MalformedURLException", Toast.LENGTH_SHORT).show();
                            }
                        });

                        Log.e("Upload file to server", "error: " + ex.getMessage(), ex);
                    } catch (Exception e) {

                        e.printStackTrace();

                        runOnUiThread(new Runnable() {
                            public void run() {
                                Toast.makeText(MainActivity.this, "Got Exception : see logcat ", Toast.LENGTH_SHORT).show();
                            }
                        });
                        Log.e("Upload Exception", "Exception : "  + e.getMessage(), e);
                    }
                    return "serverResponseCode";

                }
            }

            return null;
        }

        @Override
        protected void onPostExecute(String result) {
            Toast.makeText(getApplicationContext(), "file uploaded",
                    Toast.LENGTH_LONG).show();
        }

    }