I am facing one real issue. I need to convert image into byte array format, so that I can upload the byte array into web server. I have tried a lot however its not working. I am also getting negative values for byte array. I am not sure what i am doing wrong to take byte values in array.
Below is my code. Please help me what i am doing wrong?
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.home_menu_icon);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.JPEG, 100, bos);
byte[] data = bos.toByteArray();
Here i show code for both if your image is from GALLERY and CAMERA
if (requestCode == IMAGE_PICKER_REQUEST && resultCode == RESULT_OK) {
fileName = getRealPathFromURI(data.getData());
try {
if (bitmap != null) {
bitmap.recycle();
}
InputStream stream = getContentResolver().openInputStream(
data.getData());
bitmap = BitmapFactory.decodeStream(stream);
stream.close();
image.setImageBitmap(bitmap);
//picNameText.setText("Selected: en"
// + getStringNameFromRealPath(fileName));
ByteArrayOutputStream stream1 = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream1);
imageInByte = stream1.toByteArray();
}catch (FileNotFoundException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
if (requestCode == IMAGE_TAKER_REQUEST && resultCode == RESULT_OK) {
Bitmap photo = (Bitmap) data.getExtras().get("data");
image.setImageBitmap(photo);
ByteArrayOutputStream stream2 = new ByteArrayOutputStream();
photo.compress(Bitmap.CompressFormat.PNG, 100, stream2);
imageInByte = stream2.toByteArray();
}
enjoy it work for me.....
Try following code.
int bytes = bitmap.getByteCount();
//Create a new buffer
ByteBuffer buffer = ByteBuffer.allocate(bytes);
//Move the byte data to the buffer
b.copyPixelsToBuffer(buffer);
byte[] array = buffer.array();
A 32-bit Bitmap use a int32 to save a ARGB color, and we can use a
int array to represent a bitmap. Using Bitmap.getPixels() and
Bitmap.setPixels() to convert a Bitmap to int array and vise
verse. And a int array can be easily convert to byte array.
#Chintan Rathod also show a good solution by using Bitmap.copyPixelsToBuffer(), nearly the same with the first one.
Since your goal is to upload the bitmap to server, send a compressed
file is the best solution. Your code is just doing the right thing.
You said that you are getting negative values in byte array, which
is not an error. Just upload the byte array to server and save it as
a jpeg file.
A 32-bit Bitmap use a int32 to save a ARGB color, and we can use a int array to represent a bitmap. Using Bitmap.getPixels() and Bitmap.setPixels() to convert a Bitmap to int array and vise verse. And a int array can be easily convert to byte array.
Related
When you have an image (PNG in this case) saved as byte array on android, how can scale it to get a new image scaled in byte array format?
Have in mind that the image to scaling is to a smaller size, avoiding loss of data.
Image croping byte uri image convert byte array the step
InputStream iStream = getContentResolver().openInputStream(uri);
byte[] inputData = getBytes(iStream);
One quick way of doing this, it's letting Android to resolve the algorithm for us.
So, we convert the byte array to a bitmap, the bitmap can create a new bitmap with new sizes defined and finally convert back to byte array.
private byte[] getScaledImage(byte[] originalImage, int newWidth, int newHeight) {
// PNG has not losses, it just ignores this field when compressing
final int COMPRESS_QUALITY = 0;
// Get the bitmap from byte array since, the bitmap has the the resize function
Bitmap bitmapImage = (BitmapFactory.decodeByteArray(originalImage, 0, originalImage.length));
// New bitmap with the correct size, may not return a null object
Bitmap mutableBitmapImage = Bitmap.createScaledBitmap(bitmapImage,newWidth, newHeight, false);
// Get the byte array from tbe bitmap to be returned
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
mutableBitmapImage.compress(Bitmap.CompressFormat.PNG, 0 , outputStream);
if (mutableBitmapImage != bitmapImage) {
mutableBitmapImage.recycle();
} // else they are the same, just recycle once
bitmapImage.recycle();
return outputStream.toByteArray();
}
In my android application i want to convert image into byte array and encode into string so that i can save it on database. But after compressing image it's size becomes too small..i want to keep original size.. please help me..
final Bitmap image=(images.get(position));
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
image.compress(Bitmap.CompressFormat.PNG, 100, bytes);
byte[] b = bytes.toByteArray();
encodedImageString = Base64.encodeToString(b, Base64.DEFAULT);
You can use the following to store it in the database without compression:
Bitmap bitmap; // obtain bitmap object
int size = bitmap.getRowBytes() * bitmap.getHeight();
ByteBuffer b = ByteBuffer.allocate(size);
bitmap.copyPixelsToBuffer(b);
byte[] bytes = new byte[size];
b.get(bytes, 0, bytes.length);
Then you can store bytes in the database.
I have created a base64 string from a picture on the SD card using this(below) code, and it works but when I try to decode it (even further below) I get a java.lang.outOfMemoryException, presumably because I am not splitting the string into a reasonable size before I decode it as I am before I encode it.
byte fileContent[] = new byte[3000];
StringBuilder b = new StringBuilder();
try{
FileInputStream fin = new FileInputStream(sel);
while(fin.read(fileContent) >= 0) {
b.append(Base64.encodeToString(fileContent, Base64.DEFAULT));
}
}catch(IOException e){
}
The above code works well, but the problem comes when I try to decode the image with the following code;
byte[] imageAsBytes = Base64.decode(img.getBytes(), Base64.DEFAULT);
ImageView image = (ImageView)this.findViewById(R.id.ImageView);
image.setImageBitmap(
BitmapFactory.decodeByteArray(imageAsBytes, 0, imageAsBytes.length)
);
I have tried this way too
byte[] b = Base64.decode(img, Base64.DEFAULT);
Bitmap bitmap = BitmapFactory.decodeByteArray(b, 0, b.length);
image.setImageBitmap(bitmap);
Now I assume that I need to split the string up into sections like my image encoding code, but I have no clue how to go about doing it.
You need decode the image in Background thread like AsyncTask
or
you need reduce your image quality using BitmapFactory .
Example:
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2;
options.inPurgeable=true;
Bitmap bm = BitmapFactory.decodeFile("Your image exact loaction",options);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.JPEG, 100, baos); //bm is the bitmap object
byte[] b = baos.toByteArray();
String encodedImage = Base64.encodeToString(b, Base64.DEFAULT);
You have two problem
base64 encoding requires much more space. 3 bytes convert to 4 chars (Factor 8/3)
you read the whole file at once
in same way your first approach solved this issues. So just use that version
By that way, why are you using decodeByteArray and not decodeFile
You might try to decode to a temporary file and create image from that file.
As to base64, it is 6 bits per character, or 6x4=24 bits=3 bytes per 4 characters.
So if you take 4 characters of base64, you will not break the corresponding 3 bytes.
That is, you may split the base64-encoded data at character indices that are a multiple of 4.
I'm using the Parse SDK to build my app.
I can easily get a Bitmap out of the gallery by using Intents. I want to use them as a profile picture for my users.
However, in order to upload it I must convert it into a byte array. Also, when I download it it comes in the form of a byte array, and I must convert it back to a Drawable.
In order to convert it into a byte array, I'm doing this:
public static byte[] bitmapToByteArray(Bitmap bmp)
{
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
return byteArray;
}
I cannot find how to convert this byte[] back into a Bitmap without having to save it first. How can this process be achieved?
Just do the following:
Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
Bitmap bmp = BitmapFactory.decodeByteArray(data, 0, data.length);
I have a bitmap that I want to send to the server by encoding it to base64 but I do not want to compress the image in either png or jpeg.
Now what I was previously doing was.
ByteArrayOutputStream byteArrayBitmapStream = new ByteArrayOutputStream();
bitmapPicture.compress(Bitmap.CompressFormat.PNG, COMPRESSION_QUALITY, byteArrayBitmapStream);
byte[] b = byteArrayBitmapStream.toByteArray();
//then simple encoding to base64 and off to server
encodedImage = Base64.encodeToString(b, Base64.NO_WRAP);
Now I just dont want to use any compression nor any format plain simple byte[] from bitmap that I can encode and send to the server.
Any pointers?
You can use copyPixelsToBuffer() to move the pixel data to a Buffer, or you can use getPixels() and then convert the integers to bytes with bit-shifting.
copyPixelsToBuffer() is probably what you'll want to use, so here is an example on how you can use it:
//b is the Bitmap
//calculate how many bytes our image consists of.
int bytes = b.getByteCount();
//or we can calculate bytes this way. Use a different value than 4 if you don't use 32bit images.
//int bytes = b.getWidth()*b.getHeight()*4;
ByteBuffer buffer = ByteBuffer.allocate(bytes); //Create a new buffer
b.copyPixelsToBuffer(buffer); //Move the byte data to the buffer
byte[] array = buffer.array(); //Get the underlying array containing the data.
instead of the following line in #jave answer:
int bytes = b.getByteCount();
Use the following line and function:
int bytes = byteSizeOf(b);
protected int byteSizeOf(Bitmap data) {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB_MR1) {
return data.getRowBytes() * data.getHeight();
} else if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
return data.getByteCount();
} else {
return data.getAllocationByteCount();
}
BitmapCompat.getAllocationByteCount(bitmap);
is helpful to find the required size of the ByteBuffer