问题
I am working on an Andorid application in which I would like the user to take a picture and then to save it I am sending it over to the server. Now, I am sending the picture as a byte-array to the server. When I try to save the byte-array to a file as a PNG file, and then try to open the file, the image-viewer complains that the PNG has errors and cannot be displayed. The PNG file size was 122Kb.
When I tried to use Scalr library to resize the image, it says the image source cannot be null. Directly saving the byte-array is causing a corrupt PNG. How should I convert and send the file properly to server, so there are no errors. Here is the code for camera which I am using and sending it over.
public class AddPhotoForUser extends DrawerLoader {
private static final int CAMERA_PIC_REQUEST = 22;
Button BtnSelectImage;
private ImageView ImgPhoto;
private static volatile Bitmap photo;
private static volatile ByteArrayOutputStream stream = new ByteArrayOutputStream();
final PersonServiceImpl personService = new PersonServiceImpl();
private String[] navMenuTitles;
private TypedArray navMenuIcons;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.upload_user_photo);
navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
navMenuIcons = getResources()
.obtainTypedArray(R.array.nav_drawer_icons);
set(navMenuTitles, navMenuIcons);
Button uploadImageButton = (Button) findViewById(R.id.uploadUserImageButton);
uploadImageButton.setVisibility(View.INVISIBLE);
ImgPhoto = (ImageView) findViewById(R.id.userPhotoImageView);
BtnSelectImage = (Button) findViewById(R.id.userPhotoButtonSelect);
BtnSelectImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_PIC_REQUEST);
} catch (Exception e) {
Toast.makeText(getApplicationContext(), "Couldn't load photo", Toast.LENGTH_LONG).show();
}
}
});
uploadImageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!(v == null)) {
uploadImage();
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Intent intent = new Intent(AddPhotoForUser.this, RestaurantList.class);
startActivity(intent);
finish();
}
}
});
}
@Override
public void onBackPressed() {
Intent intent = new Intent(AddPhotoForUser.this, Login.class);
startActivity(intent);
finish();
}
@Override
public void onActivityResult(final int requestCode, int resultCode, Intent data) {
try {
switch (requestCode) {
case CAMERA_PIC_REQUEST:
if (resultCode == RESULT_OK) {
try {
photo = (Bitmap) data.getExtras().get("data");
if (!(photo == null)) {
ImgPhoto.setImageBitmap(photo);
Button uploadImageButton = (Button) findViewById(R.id.uploadUserImageButton);
uploadImageButton.setVisibility(View.VISIBLE);
}
} catch (Exception e) {
Toast.makeText(this, "Couldn't load photo", Toast.LENGTH_LONG).show();
}
}
break;
default:
break;
}
} catch (Exception e) {
e.printStackTrace();
}
}
private void uploadImage() {
if (!(photo == null)) {
photo.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
personService.addUserProfilePhoto(byteArray);
}
}
}
Here is the server side code to save the image to disk :
@Override
public Boolean updateProfilePhoto(byte[] photo) {
Person person = getCurrentlyAuthenticatedPerson();
try{
InputStream in = new ByteArrayInputStream(photo);
BufferedImage image = ImageIO.read(in);
image = Scalr.resize(image, Scalr.Method.QUALITY, 100, 100);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(image, "png", baos);
baos.flush();
File file = new File(userImagePath);
if (file.exists() && file.isDirectory()) {
OutputStream outputStream = new FileOutputStream(new File(userImagePath + person.getUserId()+".png"));
outputStream.write(baos.toByteArray());
outputStream.close();
} else {
File file1 = new File(userImagePath+person.getUserId()+".png");
if (file1.exists()) {
try {
OutputStream outputStream = new FileOutputStream(file1);
outputStream.write(baos.toByteArray());
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
} else {
boolean result = file1.createNewFile();
System.out.println("Result of file1 creation is "+result);
OutputStream outputStream = new FileOutputStream(file1);
outputStream.write(baos.toByteArray());
outputStream.close();
}
}
return true;
}catch (Exception e){
e.printStackTrace();
return false;
}
}
If I don't use the Scalr library, there are no errors, but its a corrupt file. Here is the Scalr error log :
java.lang.IllegalArgumentException: src cannot be null
at org.imgscalr.Scalr.resize(Scalr.java:1564)
at org.imgscalr.Scalr.resize(Scalr.java:1415)
at com.journaldev.spring.service.PersonServiceImpl.updateProfilePhoto(PersonServiceImpl.java:84)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:262)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy51.updateProfilePhoto(Unknown Source)
at com.journaldev.spring.Controller.PersonController.addProfilePhotoForUser(PersonController.java:100)
Any help would be nice. Thanks a lot. :-)
Updated code
public class AddPhotoForUser extends DrawerLoader {
Button BtnSelectImage;
private ImageView ImgPhoto;
private static volatile ByteArrayOutputStream stream = new ByteArrayOutputStream();
final PersonServiceImpl personService = new PersonServiceImpl();
private String[] navMenuTitles;
private TypedArray navMenuIcons;
private static final int CAMERA_PHOTO = 111;
private Uri imageToUploadUri;
Bitmap reducedSizeBitmap;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.upload_user_photo);
navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
navMenuIcons = getResources()
.obtainTypedArray(R.array.nav_drawer_icons);
set(navMenuTitles, navMenuIcons);
Button uploadImageButton = (Button) findViewById(R.id.uploadUserImageButton);
uploadImageButton.setVisibility(View.INVISIBLE);
ImgPhoto = (ImageView) findViewById(R.id.userPhotoImageView);
BtnSelectImage = (Button) findViewById(R.id.userPhotoButtonSelect);
BtnSelectImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
captureCameraImage();
} catch (Exception e) {
Toast.makeText(getApplicationContext(), "Couldn't load photo", Toast.LENGTH_LONG).show();
}
}
});
uploadImageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!(v == null)) {
uploadImage();
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Intent intent = new Intent(AddPhotoForUser.this, RestaurantList.class);
startActivity(intent);
finish();
}
}
});
}
private Bitmap getBitmap(String path) {
Uri uri = Uri.fromFile(new File(path));
InputStream in = null;
try {
final int IMAGE_MAX_SIZE = 12000000; // 12MP
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;
}
}
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);
}
@Override
public void onBackPressed() {
Intent intent = new Intent(AddPhotoForUser.this, Login.class);
startActivity(intent);
finish();
}
@Override
protected void onActivityResult(final 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);
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();
}
}
}
private void uploadImage() {
if(!(reducedSizeBitmap == null)){
reducedSizeBitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
this.personService.addUserProfilePhoto(byteArray);
}
}
}
回答1:
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!
回答2:
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;
}
来源：https://stackoverflow.com/questions/32245091/taking-a-picture-via-camera-and-sending-it-to-server-in-bytearray