Develop Reference

get raw file data from url and display in ImageView

I would like to display an image from the URL that is providing me raw data for the image(png or JPG).
I checked this link but not much useful.
Here is my image link
I am processing the raw data but could not see the image. I am not sure how do I check that I got the right raw data.
here is my effort
private class DownloadImageTask extends AsyncTask<String, Void, Void> {
byte[] bytes;
Bitmap picture = null;
#Override
protected Void doInBackground(String... urls) {
// final OkHttpClient client = new OkHttpClient();
//
// Request request = new Request.Builder()
// .url(urls[0])
// .build();
//
// Response response = null;
//
// try {
// response = client.newCall(request).execute();
// } catch (IOException e) {
// e.printStackTrace();
// }
// assert response != null;
// if (response.isSuccessful()) {
// try {
// assert response.body() != null;
// ByteArrayOutputStream baos = new ByteArrayOutputStream();
// IOUtils.copy(response.body().byteStream(), baos);
// bytes = baos.toByteArray();
// picture = BitmapFactory.decodeStream(response.body().byteStream());
// } catch (Exception e) {
// Log.e("Error", Objects.requireNonNull(e.getMessage()));
// e.printStackTrace();
// }
//
// }
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
try {
URL url = new URL(urls[0]);
byte[] chunk = new byte[4096];
int bytesRead;
InputStream stream = url.openStream();
while ((bytesRead = stream.read(chunk)) > 0) {
outputStream.write(chunk, 0, bytesRead);
}
} catch (IOException e) {
e.printStackTrace();
return null;
}
bytes = outputStream.toByteArray();
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
if (bytes != null) {
Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
cameraView.setImageBitmap(bitmap);
}
// cameraView.setImageBitmap(picture);
}
}

The location of your problem/s in your workflow seems ill-determined.
You should first identify this.
(Plus, you did not specify if you are bound to a specific programming language).
For this sake, I suggest you:
Start using a raw image file that you know is correct, and test its processing.
There are quite a few raw image formats.
Judging from the tag android, I guess the following can help:
To capture a raw iamge into a file: How to capture raw image from android camera
To display in ImageView: Can't load image from raw to imageview
https://gamedev.stackexchange.com/questions/14046/how-can-i-convert-an-image-from-raw-data-in-android-without-any-munging
https://developer.android.com/reference/android/graphics/ImageFormat
https://www.androidcentral.com/raw-images-and-android-everything-you-need-know
Try getting a raw image from an URL that you can manage.
Apply this to the actual target URL.
This way you will know where your problem resides.
Without more info it is hard to "debug" your problem.
You can also inspect code in FOSS projects.

You could use a library named Picasso and do the following:
String url = get url from the Async Function and convert it to String
/*if you url has no image format, you could do something like this con convert the uri into a Bitmap*/
public Bitmap getCorrectlyOrientedImage(Context context, Uri uri, int maxWidth)throws IOException {
InputStream input = context.getContentResolver().openInputStream(uri);
BitmapFactory.Options onlyBoundsOptions = new BitmapFactory.Options();
onlyBoundsOptions.inJustDecodeBounds = true;
onlyBoundsOptions.inDither = true;//optional
onlyBoundsOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;//optional
BitmapFactory.decodeStream(input, null, onlyBoundsOptions);
try {
input.close();
} catch (NullPointerException e) {
e.printStackTrace();
}
/*trying to get the right orientation*/
if ((onlyBoundsOptions.outWidth == -1) || (onlyBoundsOptions.outHeight == -1)) {
return null;
}
int originalSize = Math.max(onlyBoundsOptions.outHeight, onlyBoundsOptions.outWidth);
double ratio = (originalSize > maxWidth) ? (originalSize / maxWidth) : 1.0;
Matrix matrix = new Matrix();
int rotationInDegrees = exifToDegrees(orientation);
if (orientation != 0) matrix.preRotate(rotationInDegrees);
int bmpWidth = 0;
try {
assert bitmap != null;
bmpWidth = bitmap.getWidth();
} catch (NullPointerException e) {
e.printStackTrace();
}
Bitmap adjustedBitmap = bitmap;
if (bmpWidth > 0)
adjustedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
return adjustedBitmap;
}
/*Then you has the image in Bitmap, you can use the solution below or if Picasso doesn't allows you to put Bitmap you can pass it directly to the ImageView as a Bitmap.*/
ImageView imageView = view.findViewById(R.id.imageViewId);
/*Then use Picasso to draw the image into the ImageView*/
Picasso.with(context).load(url).fit().into(imageView );
This is the dependency for build.gradle, not sure if is the last version but you could try.
implementation 'com.squareup.picasso:picasso:2.5.2'
Kind regards!

Identify the following questions:
Using URL to get bytes to load images
I wrote down what I can with reference to
class DownLoadImageTask extends AsyncTask<String, Void, Bitmap> {
#Override
protected void onPostExecute(Bitmap bitmap) {
super.onPostExecute(bitmap);
imageView.setImageBitmap(bitmap);
}
#Override
protected Bitmap doInBackground(String... strings) {
try {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder().url(strings[0]).build();
Response response = client.newCall(request).execute();
if (response.isSuccessful()) {
InputStream inputStream = response.body().byteStream();
return BitmapFactory.decodeStream(inputStream);
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
This is the URL I use
https://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Image_created_with_a_mobile_phone.png/440px-Image_created_with_a_mobile_phone.png
https://upload.wikimedia.org/wikipedia/commons/3/3a/Cat03.jpg
I can test it. I hope it can help you

How to convert a bitmap into a File android? [duplicate]

This question already has answers here:
Save bitmap to location
(19 answers)
Closed 6 years ago.
I have an image in drawable. I just need to convert this image into a file. How can i achieve this?

Try this it works:--
private File saveBitmap(Bitmap bitmap, String path) {
File file = null;
if (bitmap != null) {
file = new File(path);
try {
FileOutputStream outputStream = null;
try {
outputStream = new FileOutputStream(path); //here is set your file path where you want to save or also here you can set file object directly
bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream); // bitmap is your Bitmap instance, if you want to compress it you can compress reduce percentage
// PNG is a lossless format, the compression factor (100) is ignored
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (outputStream != null) {
outputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
return file;
}

Proper strategy of getting byte content of big images from Gallery when OutOfMemoryError is thrown

First of all I would like to say, that loading big images strategy is described here. I am aware of the obligation to resize the image to omit OutOfMemoryError. I would like to get bytes from the image to be able to send it through Internet.
public byte[] getAttachment(Context context, String fullFilePath) {
byte[] fileBytes = mFileUtil.readFileAsBytes(fullFilePath);
if (fileBytes == null) {
Logger.i("Unable to get bytes, trying through content resolver");
try {
fileBytes = mFileUtil.readFileFromContentResolver(context, fullFilePath);
} catch (OutOfMemoryError e) {
Uri imageUri = Uri.parse(fullFilePath);
if (checkIfFileIsImage(context, imageUri)) {
try {
InputStream stream = context.getContentResolver().openInputStream(imageUri);
if (stream == null) {
return null;
}
BitmapFactory.Options options = getOptions(stream, 2000, 2000);
stream.close();
stream = context.getContentResolver().openInputStream(imageUri);
if (stream == null) {
return null;
}
Bitmap bitmap = BitmapFactory.decodeStream(stream, null, options);
bitmap = rotateBitmap(context, imageUri, bitmap);
stream.close();
fileBytes = convertBitmapToArray(bitmap);
} catch (Exception e1) {
Logger.e("Unable to get bytes using fallback method, attachment " +
"will not be added");
} catch (OutOfMemoryError e2) {
Logger.e("Unable to get bytes using fallback method, because " +
"attachment is too big. Attachment will not be added");
}
}
System.gc();
}
}
return fileBytes;
}
FileUtil.class
public byte[] readFileAsBytes(String fileName) {
File originalFile = new File(fileName);
byte[] bytes = null;
try {
FileInputStream fileInputStreamReader = new FileInputStream(originalFile);
bytes = new byte[(int) originalFile.length()];
fileInputStreamReader.read(bytes);
} catch (IOException e) {
}
return bytes;
}
public byte[] readFileFromContentResolver(Context context, String fileName) {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
InputStream is = null;
InputStream inputStream = null;
try {
inputStream = context.getContentResolver().openInputStream(Uri.parse(fileName));
is = new BufferedInputStream(inputStream);
byte[] data = new byte[is.available()];
is.read(data);
bos.write(data);
} catch (Exception e) {
} finally {
try {
if (is != null) {
is.close();
}
if (inputStream != null) {
inputStream.close();
}
} catch (IOException e1) {
}
}
return bos.toByteArray();
}
As you can see the aim of this code is to get byte[] from Bitmap unlike here. It works without problems in almost any case. However it is especially error prone on low-end devices with older Android systems (but also very rarely).
I don't like the idea of setting largeHeap inside AndroidManifest.xml as this is just masking the problem rather than cope with it. I also would not like to send even smaller images.
Could this piece of code be improved in any other way in order to get rid of OutOfMemoryError?

Android : bitmap is null when getting data from caching using Voley

I am using volley library and displaying image successfully. I want to get same downloaded image from cache . This is my code :
private Bitmap getBitmapFromUrl(String url){
String str = "" ;
Bitmap bitmap = null ;
byte[] bytes = null ;
Cache cache = AppController.getInstance().getRequestQueue().getCache();
Entry entry = cache.get(url);
try {
str = new String(entry.data, "UTF-8");
bytes = str.getBytes("UTF_8") ;
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeByteArray( bytes, 0,bytes.length,options);
Log.i(PostItemAdapter.class.getSimpleName(), bitmap+"");
return bitmap ;
}
My issue is that the bitmap object is null .
Can any one tell me why ? thanks in advance .

My problem solved using the aid of this great link where I copied the three files in their images package :
DiskLruImageCache
ImageCacheManager
BitmapLruImageCache
Also I copied RequestManager file. Also there was an issue faced me in the DiskLruImageCache when creating the key from the URL, and I solved this by replacing few lines in this file.
The solution
-old code:
First
#Override
public Bitmap getBitmap( String key ) {
Bitmap bitmap = null;
DiskLruCache.Snapshot snapshot = null;
try {
snapshot = mDiskCache.get( key );
....... etc
Second
#Override
public void putBitmap( String key, Bitmap data ) {
DiskLruCache.Editor editor = null;
try {
editor = mDiskCache.edit( key );
......etc
-new code:
First
#Override
public Bitmap getBitmap( String key ) {
Bitmap bitmap = null;
DiskLruCache.Snapshot snapshot = null;
try {
snapshot = mDiskCache.get( ImageCacheManager.getInstance().createKey(key) );
....etc
Second
#Override
public void putBitmap( String key, Bitmap data ) {
DiskLruCache.Editor editor = null;
try {
editor = mDiskCache.edit( ImageCacheManager.getInstance().createKey(key) );
.....etc
Note : All this modification in DiskLruImageCache , Beside the caching you can save images to SD Card by this function :
private void saveImageToSD(Bitmap bmp) {
bytes = new ByteArrayOutputStream();
bmp.compress(mCompressFormat, 90, bytes);
file = new File(Environment.getExternalStorageDirectory()+File.separator+"myImage"+(++i)+".jpg");
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
/*--- create a new FileOutputStream and write bytes to file ---*/
try {
fos = new FileOutputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
try {
fos.write(bytes.toByteArray());
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
And calling to this function be inside the getBitmap(String URL) function witch inside the DiskLruImageCache file .

how to Read Base64 encode image file remotely

I have a image file which I uploaded to server using Base64 encoding(By converting to string).
The server stored that string in a text file and gave me the url to that text file.
Can anybody guide me for, how can I get the encoded string from that text file remotely?

Use this to decode/encode (only Java way)
public static BufferedImage decodeToImage(String imageString) {
BufferedImage image = null;
byte[] imageByte;
try {
BASE64Decoder decoder = new BASE64Decoder();
imageByte = decoder.decodeBuffer(imageString);
ByteArrayInputStream bis = new ByteArrayInputStream(imageByte);
image = ImageIO.read(bis);
bis.close();
} catch (Exception e) {
e.printStackTrace();
}
return image;
}
public static String encodeToString(BufferedImage image, String type) {
String imageString = null;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
try {
ImageIO.write(image, type, bos);
byte[] imageBytes = bos.toByteArray();
BASE64Encoder encoder = new BASE64Encoder();
imageString = encoder.encode(imageBytes);
bos.close();
} catch (IOException e) {
e.printStackTrace();
}
return imageString;
}
Hope it's help
Update
Android way
To get image from Base64 string use
byte[] decodedString = Base64.decode(encodedImage, Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
UPDATE2
For reading text file from server, use this:
try {
URL url = new URL("example.com/example.txt");
BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
String str;
while ((str = in.readLine()) != null) {
// str is one line of text; readLine() strips the newline character(s)
}
in.close();
} catch (MalformedURLException e) {
} catch (IOException e) {
}
And next time try to ask correct.