通过相机捕获的图像质量丢失
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【中文标题】通过相机捕获的图像质量丢失【英文标题】：Quality of image captured through camera is lost 【发布时间】：2016-02-18 12:57:25 【问题描述】：我正在从相机捕获图像并将其发送到服务器。成功发布到服务器后，我将图像显示为相对布局中的背景。我的问题是图像质量丢失并且显示时图像被拉伸相对布局的背景。截图如下：
点击相机时
//On clicking Camera
imgCamera.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
// Checking camera availability
if (!isDeviceSupportCamera())
Toast.makeText(getApplicationContext(),
"Sorry! Your device doesn't support camera",
Toast.LENGTH_LONG).show();
// will close the app if the device doesn't have camera
finish();
else
//cameraClick(view);
captureImage();
);
CaptureImage() 方法：
private void captureImage()
Log.e("Capture Image", "Called");
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// creating Dir to save clicked Photo
String root = Environment.getExternalStorageDirectory().toString();
Log.e("root", root);
String directory_path = root + "/cam_intent/";
File myDir = new File(directory_path);
myDir.mkdirs();
// save clicked pic to given dir with given name
File file = new File(myDir, "MyPhoto.jpg");
fileUri = Uri.fromFile(file);
Log.e("Uri of File", String.valueOf(fileUri));
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
onActivityResult()
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
Log.e("onActivityResult", "Called");
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE && resultCode == RESULT_OK)
launchUploadActivity(true);
launchUploadActivity()
private void launchUploadActivity(boolean isImage)
if (fileUri.getPath() != null)
// Displaying the image or video on the screen
Log.e("Launch Upload Activity", "Called");
previewMedia(isImage);
else
Toast.makeText(getApplicationContext(),
"Sorry, file path is missing!", Toast.LENGTH_LONG).show();
previewMedia()
private void previewMedia(boolean isImage)
// Checking whether captured media is image or video
if (isImage)
Log.e("Preview Media", "Called");
//Uploading image to server
new UploadFileToServer().execute();
上传文件到服务器
private class UploadFileToServer extends AsyncTask<Void, Integer, String>
@Override
protected void onPreExecute()
// setting progress bar to zero
// progressBar.setProgress(0);
super.onPreExecute();
@Override
protected void onProgressUpdate(Integer... progress)
// Making progress bar visible
//progressBar.setVisibility(View.VISIBLE);
//Making progress dialog visible
progressDialog.show();
// updating progress bar value
// progressBar.setProgress(progress[0]);
// updating percentage value
//txtPercentage.setText(String.valueOf(progress[0]) + "%");
@Override
protected String doInBackground(Void... params)
return uploadFile();
@SuppressWarnings("deprecation")
private String uploadFile()
Log.e("upload File", "called");
String responseString = null;
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(file_upload_url);
try
androidMultiPartEntity entity = new AndroidMultiPartEntity(
new AndroidMultiPartEntity.ProgressListener()
@Override
public void transferred(long num)
publishProgress((int) ((num / (float) totalSize) * 100));
);
// Adding file data to http body
if (val == 0)
Log.e("val = ", String.valueOf(val));
File sourceFile = new File(fileUri.getPath());
if (sourceFile != null)
Log.e("SoureFile", String.valueOf(sourceFile));
photosize = 0;
entity.addPart("image", new FileBody(sourceFile));
else
photosize = 1;
Toast.makeText(ProfileActivity.this, "Please Upload Your Image", Toast.LENGTH_LONG).show();
else
File sourceFile = new File(picturePath);
if (sourceFile != null)
photosize = 0;
entity.addPart("image", new FileBody(sourceFile));
else
photosize = 1;
Toast.makeText(ProfileActivity.this, "Please Upload Your Image", Toast.LENGTH_LONG).show();
totalSize = entity.getContentLength();
Log.e("Total Size", String.valueOf(totalSize));
httppost.setEntity(entity);
// Making server call
HttpResponse response = httpclient.execute(httppost);
HttpEntity r_entity = response.getEntity();
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == 200)
// Server response
responseString = EntityUtils.toString(r_entity);
else
responseString = "Error occurred! Http Status Code: "
+ statusCode;
catch (ClientProtocolException e)
responseString = e.toString();
catch (IOException e)
responseString = e.toString();
return responseString;
@Override
protected void onPostExecute(String result)
Log.e("UpLoad Server", "Response from server: " + result);
try
JSONObject jsonObject = new JSONObject(result);
String statusCode = jsonObject.getString("statusCode");
if (statusCode.equals("200"))
JSONObject detail = jsonObject.getJSONObject("detail");
String relativePath = detail.getString("relative_path");
JSONObject uploadData = detail.getJSONObject("upload_data");
String fileName = uploadData.getString("file_name");
//Getting Base URL
base_url = apiConfiguration.getApi();
completeURL = base_url + relativePath + "/" + fileName;
Log.e("Complete URl", completeURL);
//Entering the new value of complete url in shared preference
//editor.remove(Prefs_Registration.get_user_complete_url);
editor.putString(Prefs_Registration.get_user_complete_url, completeURL);
editor.commit();
new GetBitmapFromURL().execute();
else
Toast.makeText(getApplicationContext(), "Image not uploaded", Toast.LENGTH_SHORT).show();
catch (JSONException e)
e.printStackTrace();
progressDialog.dismiss();
// showing the server response in an alert dialog
//showAlert(result);
super.onPostExecute(result);
/**
* Method to show alert dialog
*/
private void showAlert(String message)
AlertDialog.Builder builder = new AlertDialog.Builder(ProfileActivity.this);
builder.setMessage(message)
.setTitle("Response from Servers")
.setCancelable(false)
.setPositiveButton("OK", new DialogInterface.OnClickListener()
public void onClick(DialogInterface dialog, int id)
// do nothing
);
AlertDialog alert = builder.create();
alert.show();
GetImageFromURL
// Get Image from Thumbnail URL
class GetBitmapFromURL extends AsyncTask<String, String, Bitmap>
Bitmap myBitmap;
@Override
protected Bitmap doInBackground(String... strings)
URL url = null;
try
url = new URL(completeURL);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
myBitmap = BitmapFactory.decodeStream(input);
catch (MalformedURLException e)
e.printStackTrace();
catch (IOException e)
e.printStackTrace();
return myBitmap;
@Override
protected void onPostExecute(Bitmap bitmap)
Drawable dr = new BitmapDrawable(bitmap);
Log.e("DrawableN", String.valueOf(dr));
//Setting the image
relativeLayout.setBackgroundDrawable(dr);
在 onPostExecute() 方法中，我将图像设置在相对布局的背景中。
XML
<RelativeLayout
android:id="@+id/rel"
android:layout_
android:layout_
android:layout_marginBottom="@dimen/margin10"
android:layout_marginLeft="@dimen/margin10"
android:layout_marginRight="@dimen/margin10"
android:layout_marginTop="@dimen/margin10">
<ImageView
android:id="@+id/arrowProfile"
android:layout_
android:layout_
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:paddingLeft="@dimen/padding10"
android:src="@drawable/back_signup" />
<com.almabay.almachat.circularImageView.CircularImageView
android:id="@+id/cam"
android:layout_
android:layout_
android:layout_alignParentRight="true"
android:paddingRight="@dimen/padding10"
android:background="@drawable/camera1"/>
<TextView
android:id="@+id/userName"
android:layout_
android:layout_
android:layout_above="@+id/status"
android:layout_alignParentBottom="true"
android:layout_marginBottom="@dimen/margin20"
android:paddingLeft="@dimen/padding10"
android:text="User Name"
android:textColor="#ffffff"
android:textSize="20sp" />
<TextView
android:id="@+id/status"
android:layout_
android:layout_
android:layout_alignParentBottom="true"
android:paddingLeft="@dimen/padding10"
android:text="Status of user"
android:textColor="#ffffff" />
</RelativeLayout>
我将图像作为多部分发送到服务器。请告诉我如何在相对布局上渲染时保持图像的质量。
【问题讨论】：
您发布了或者更好的说法是倾倒了很多代码。我们应该挖掘这一切吗？只需将代码发布到所有内容即可。只是导致问题的一小段代码。 现在请检查代码。我只提到了我将图像发送到服务器并以相对布局显示的代码。 质量下降和拉伸是两件事。两者都真的发生了吗？我们可以看到拉伸是的。 我认为只有拉伸。 我不明白这与发布到服务器有什么关系。您不能只发布将图像文件放入图像视图的代码吗？否则请解释为什么它们首先连接。 【参考方案1】：您的 ImageView 的纵横比应该等于捕获的图像的纵横比。
【讨论】：
我在相对布局的背景中显示图像。我没有在图像视图中显示它。 嗯，这也可能是个问题……我个人从来没有这样做过，但我猜长宽比应该匹配。以上是关于通过相机捕获的图像质量丢失的主要内容，如果未能解决你的问题，请参考以下文章
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