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How to save an image in Android without compressing?

I'm making an Android application that captures images and stores them in the internal memory, but to save the images are compressed and I want to be saved in its original size without any compression.
This is the code I am using to store images, as I do so not me compress ??
ContextWrapper cw = new ContextWrapper(context);
File directory = cw.getDir("imageDir", Context.MODE_PRIVATE);
File mypath = new File(directory, "TheChat" + (System.currentTimeMillis()/1000) + "Avatar.jpg");
FileOutputStream fileOutputStream = null;
try {
fileOutputStream = new FileOutputStream(mypath);
bitmapImage.compress(Bitmap.CompressFormat.PNG, 100, fileOutputStream);
}
catch (Exception e) {
e.printStackTrace();
}
finally {
try {
if (fileOutputStream != null) {
fileOutputStream.flush();
fileOutputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

Save it as a BLOB (bytearray), then reconvert it to a bitmap upon loading it. If it's for internal use only it should work fine. If you're not compressing it at all you might as well save it in a straight-forward format.

My app can create a file, but cannot read it

I write a file in internal memory:
byte[] data = ... // (A buffer containing wav data)
String filename = context.getFilesDir().getAbsolutePath() + "/newout.wav";
File file = new File(filename);
FileOutputStream fos = new FileOutputStream(file);
fos.write(data);
fos.close();
Then I try to play it:
MediaPlayer player = new MediaPlayer();
player.setDataSource(filename);
player.prepare();
player.setLooping(false);
player.start();
But the prepare() fails:
java.io.IOException: Prepare failed.: status=0x1
I checked the file and saw that it's permission is -rw-------. I changed it to -rw-r--r--, after that it was being played successfully.
So how come my app can write a file, but can't read it? And how can I make the FileOutputStream to set the permissions right?

To change programaticaly the file permissions to -rw-r--r-- you need to do smoething like this:
Process process = null;
DataOutputStream dataOutputStream = null;
try {
process = Runtime.getRuntime().exec("su");
dataOutputStream = new DataOutputStream(process.getOutputStream());
dataOutputStream.writeBytes("chmod 644 FilePath\n");
dataOutputStream.writeBytes("exit\n");
dataOutputStream.flush();
process.waitFor();
} catch (Exception e) {
return false;
} finally {
try {
if (dataOutputStream != null) {
dataOutputStream.close();
}
process.destroy();
} catch (Exception e) {
System.out.println(e.getMessage());
}
}

If you open a file, the default mode is Context.MODE_PRIVATE, e.g. as in
File file = new File(context.getFilesDir(), filename);
String filename = "myfile";
String string = "Hello world!";
FileOutputStream outputStream;
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
outputStream.write(string.getBytes());
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
(taken from the documentation). Modes MODE_WORLD_READABLE and MODE_WORLD_WRITABLE are deprecated and do not work on newer devices. So I'd say you should rather write on the external storage to make contents available to other apps.
Note: as per documentation:
External storage:
"It's world-readable, so files saved here may be read outside of your control."

Convert encoded base64 image to File object in Android

I am trying to use the AndroidImageSlider library and populate it with images that I have downloaded as a base64 string.
The library only accepts URLs, R.drawable values, and the File object as parameters.
I am trying to convert the image string to a File object in order to be passed to the library function. I have been able to decode from base_64 and convert to a byte[] so far.
String imageData;
byte[] imgBytesData = android.util.Base64.decode(imageData, android.util.Base64.DEFAULT);

You'll need to save the File object to disk for that to work. This method will save the imageData string to disk and return the associated File object.
public static File saveImage(final Context context, final String imageData) {
final byte[] imgBytesData = android.util.Base64.decode(imageData,
android.util.Base64.DEFAULT);
final File file = File.createTempFile("image", null, context.getCacheDir());
final FileOutputStream fileOutputStream;
try {
fileOutputStream = new FileOutputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
return null;
}
final BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(
fileOutputStream);
try {
bufferedOutputStream.write(imgBytesData);
} catch (IOException e) {
e.printStackTrace();
return null;
} finally {
try {
bufferedOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return file;
}
It creates a temporary file in your applications 'cache' directory. However, you are still responsible for deleting the file once you no longer need it.

IllegalArgumentException: File contains a path separator Android

I'm trying to write to an output file on my HTC One and get the following message in the LogCat:
11-21 08:05:18.228: W/System.err(6609): java.lang.IllegalArgumentException: File /storage/emulated/0/com.example.pattern1/myfile.txt contains a path separator
The source code is given below:
protected void writeToFile(String string){
File patternDirectory = new File(Environment.getExternalStorageDirectory().getAbsolutePath().toString()+"/com.example.pattern1/myfile.txt");
patternDirectory.mkdirs();
FileOutputStream outputStream;
try {
outputStream = openFileOutput(patternDirectory.getAbsolutePath().toString(), Context.MODE_APPEND);
outputStream.write(string.getBytes());
TextView t = (TextView)findViewById(R.id.bottomMidText);
t.setText(patternDirectory.getAbsolutePath().toString());
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
I would appreciate if someone can help identify the problem.

The openFileInput method will not accept path separators.('/')
it accepts only the name of the file which you want to open/access. so change the statement
outputStream = openFileOutput(patternDirectory.getAbsolutePath().toString(), Context.MODE_APPEND);
to
outputStream = new FileOutputStream (new File(patternDirectory.getAbsolutePath().toString()), true); // true will be same as Context.MODE_APPEND

One problem may be the fact that you do:
Environment.getExternalStorageDirectory().getAbsolutePath().toString()+"/com.example.pattern1/myfile.txt"
You create a directory that has name myfile.txt

Writing a File in Android

First of all, I'm sorry if exists a similar post but I was not able to understand.
I'm trying to write a file in android and I got the following code:
String FILENAME = "hello_file.txt";
String string = "hello world!";
FileOutputStream fos;
try {
fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
fos.write(string.getBytes());
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
Log.d("Angles", "FileNotFoundException");
}catch(IOException e){
e.printStackTrace();
Log.d("Angles", "IOException");
}
I don't get any exception so I suppose it works but I'm not able to find the hello_file.txt file inside the device.
I'm running on Galaxy Nexus; no sd.

If you want to create a file in sdcard, you need to use
File f = new File (Environment.getExternalStorageDirectory(),"myfile.txt")