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Save bitmap to location

I am working on a function to download an image from a web server, display it on the screen, and if the user wishes to keep the image, save it on the SD card in a certain folder. Is there an easy way to take a bitmap and just save it to the SD card in a folder of my choice?

My issue is that I can download the image, display it on screen as a Bitmap. The only way I have been able to find to save an image to a particular folder is to use FileOutputStream, but that requires a byte array. I am not sure how to convert (if this is even the right way) from Bitmap to byte array, so I can use a FileOutputStream to write the data.

The other option I have is to use MediaStore :

MediaStore.Images.Media.insertImage(getContentResolver(), bm,
    barcodeNumber + ".jpg Card Image", barcodeNumber + ".jpg Card Image");

Which works fine to save to SD card, but does not allow you to customize the folder.

Exactly what I'm doing in my app. I download a large image form webserver manipulate it and load the bitmap directly to an imageview via mImage.setImageBitmap(_result.getBitmap()); in my onTaskComplete() callback. I now have to allow users to save the file locally if they want via long press context menu. I should be able to use the solution below. What i want to know though, did you discover a better approach to this?
There is a way elegant way of doing it here: stackoverflow.com/questions/4263375/…

m
michael-slx
try (FileOutputStream out = new FileOutputStream(filename)) {
    bmp.compress(Bitmap.CompressFormat.PNG, 100, out); // bmp is your Bitmap instance
    // PNG is a lossless format, the compression factor (100) is ignored
} catch (IOException e) {
    e.printStackTrace();
}

I have also compressed the image but to 100 percent and when I am getting my image in canvas it is very small. any reason?
@Aizaz This will not change the size of the image, only the format and (potentially) quality. It is also worth noting that the compression quality, 90, in the example above will not have any effect when saving as a PNG, but will make a difference for JPEG's. In the case of a JPEG, you can choose any number between 0 and 100.
Does one have to recompress? I just want to save the original image.
@HeinduPlessis Don't have to but you probably should. Saving the raw bitmap will take much more space, depending on the format (ARGB_4444 vs ARGB_8888 for example).
Surely its better to use the context to get the correct path to ensure the correct location should it change: FileOutputStream out = context.openFileOutput(filename, Context.MODE_PRIVATE); Where private is not the SDCARD location.
C
Chepech

You should use the Bitmap.compress() method to save a Bitmap as a file. It will compress (if the format used allows it) your picture and push it into an OutputStream.

Here is an example of a Bitmap instance obtained through getImageBitmap(myurl) that can be compressed as a JPEG with a compression rate of 85% :

// Assume block needs to be inside a Try/Catch block.
String path = Environment.getExternalStorageDirectory().toString();
OutputStream fOut = null;
Integer counter = 0;
File file = new File(path, "FitnessGirl"+counter+".jpg"); // the File to save , append increasing numeric counter to prevent files from getting overwritten.
fOut = new FileOutputStream(file);

Bitmap pictureBitmap = getImageBitmap(myurl); // obtaining the Bitmap
pictureBitmap.compress(Bitmap.CompressFormat.JPEG, 85, fOut); // saving the Bitmap to a file compressed as a JPEG with 85% compression rate
fOut.flush(); // Not really required
fOut.close(); // do not forget to close the stream

MediaStore.Images.Media.insertImage(getContentResolver(),file.getAbsolutePath(),file.getName(),file.getName());

@JoaquinG any reason for that fOut.flush() isn't it possible to omit it?
@Niklas I think that you can omit flush.
You should change the wording from "compression rate of 85%" to "quality rate of 85%" for less ambiguity. I would interpret "compression rate of 85%" to mean "15% quality," but the int parameter of Bitmap.compress specifies quality.
can you plz post the method getImageBitmap(myurl)
P
Pratik Butani
outStream = new FileOutputStream(file);

will throw exception without permission in AndroidManifest.xml (at least in os2.2):

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

Not if your file absolutePath is an internal path?
r
rayryeng

Inside onActivityResult:

String filename = "pippo.png";
File sd = Environment.getExternalStorageDirectory();
File dest = new File(sd, filename);

Bitmap bitmap = (Bitmap)data.getExtras().get("data");
try {
     FileOutputStream out = new FileOutputStream(dest);
     bitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
     out.flush();
     out.close();
} catch (Exception e) {
     e.printStackTrace();
}

you're calling it "pippo.jpg" but you're using PNG compression
compress format should be .JPEG if you want to change quality of bitmap. Quality can not be changed in PNG format.
s
shinydev

Some formats, like PNG which is lossless, will ignore the quality setting.


PNG is still a compressed format. Does the quality setting not modify the compression quality?
The docs state (highlighting by me): Hint to the compressor, 0-100. 0 meaning compress for small size, 100 meaning compress for max quality. Some formats, like PNG which is lossless, will ignore the quality setting
A
A-Droid Tech

Here is the sample code for saving bitmap to file :

public static File savebitmap(Bitmap bmp) throws IOException {
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    bmp.compress(Bitmap.CompressFormat.JPEG, 60, bytes);
    File f = new File(Environment.getExternalStorageDirectory()
            + File.separator + "testimage.jpg");
    f.createNewFile();
    FileOutputStream fo = new FileOutputStream(f);
    fo.write(bytes.toByteArray());
    fo.close();
    return f;
}

Now call this function to save the bitmap to internal memory.

File newfile = savebitmap(bitmap);

I hope it will help you. Happy codeing life.


B
Bhushan Firake

Why not call the Bitmap.compress method with 100 (which sounds like it is lossless)?


Even though it is ignored it should be 100. If someday the compress format is changed to a loosely one then the image will most closely match it being loosely. Also note if you have code that abstracts this call this maybe more important.
100% isn't lossless with JPEG, FWIW. You can verify this by loading and saving the bitmap repeatedly.
Z
Ziem
Bitmap bbicon;

bbicon=BitmapFactory.decodeResource(getResources(),R.drawable.bannerd10);
//ByteArrayOutputStream baosicon = new ByteArrayOutputStream();
//bbicon.compress(Bitmap.CompressFormat.PNG,0, baosicon);
//bicon=baosicon.toByteArray();

String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
OutputStream outStream = null;
File file = new File(extStorageDirectory, "er.PNG");
try {
    outStream = new FileOutputStream(file);
    bbicon.compress(Bitmap.CompressFormat.PNG, 100, outStream);
    outStream.flush();
    outStream.close();
} catch(Exception e) {

}

you dont need to flush the outStream if you are passing that in 'compress' method . that method will do behalf of you.
V
Vahe Gharibyan

I know this question is old, but now we can achieve the same result without WRITE_EXTERNAL_STORAGE permission. Instead of we can use File provider.

private fun storeBitmap(bitmap: Bitmap, file: File){
        requireContext().getUriForFile(file)?.run {
            requireContext().contentResolver.openOutputStream(this)?.run {
                bitmap.compress(Bitmap.CompressFormat.JPEG, 100, this)
                close()
            }
        }
    }

How to retrieve file from provider ?

fun Context.getUriForFile(file: File): Uri? {
        return FileProvider.getUriForFile(
            this,
            "$packageName.fileprovider",
            file
        )
    }

Also do not forget register your provider in Android manifest

<provider
        android:name="androidx.core.content.FileProvider"
        android:authorities="${applicationId}.fileprovider"
        android:exported="false"
        android:grantUriPermissions="true">
        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/file_paths"/>
    </provider>

Works like a charm!!! enough for share a photo
u
user511895

I would also like to save a picture. But my problem(?) is that I want to save it from a bitmap that ive drawed.

I made it like this:

 @Override
 public boolean onOptionsItemSelected(MenuItem item) {
            switch (item.getItemId()) {
            case R.id.save_sign:      

                myView.save();
                break;

            }
            return false;    

    }

public void save() {
            String filename;
            Date date = new Date(0);
            SimpleDateFormat sdf = new SimpleDateFormat ("yyyyMMddHHmmss");
            filename =  sdf.format(date);

            try{
                 String path = Environment.getExternalStorageDirectory().toString();
                 OutputStream fOut = null;
                 File file = new File(path, "/DCIM/Signatures/"+filename+".jpg");
                 fOut = new FileOutputStream(file);

                 mBitmap.compress(Bitmap.CompressFormat.JPEG, 85, fOut);
                 fOut.flush();
                 fOut.close();

                 MediaStore.Images.Media.insertImage(getContentResolver()
                 ,file.getAbsolutePath(),file.getName(),file.getName());

            }catch (Exception e) {
                e.printStackTrace();
            }

 }

your save method only works for me.. after wasting some hours.. thanks a lot Sir.
J
JulienGenoud

The way I found to send PNG and transparency.

String file_path = Environment.getExternalStorageDirectory().getAbsolutePath() +
                    "/CustomDir";
File dir = new File(file_path);
if(!dir.exists())
  dir.mkdirs();

String format = new SimpleDateFormat("yyyyMMddHHmmss",
       java.util.Locale.getDefault()).format(new Date());

File file = new File(dir, format + ".png");
FileOutputStream fOut;
try {
        fOut = new FileOutputStream(file);
        yourbitmap.compress(Bitmap.CompressFormat.PNG, 85, fOut);
        fOut.flush();
        fOut.close();
     } catch (Exception e) {
        e.printStackTrace();
 }

Uri uri = Uri.fromFile(file);     
Intent intent = new Intent(android.content.Intent.ACTION_SEND);
intent.setType("image/*");
intent.putExtra(android.content.Intent.EXTRA_SUBJECT, "");
intent.putExtra(android.content.Intent.EXTRA_TEXT, "");
intent.putExtra(Intent.EXTRA_STREAM, uri);

startActivity(Intent.createChooser(intent,"Sharing something")));

The value 85 here doesn't make sense as PNG is lossless. The documentation says - ` Some formats, like PNG which is lossless, will ignore the quality setting`
B
Bhavik Nathani

Save Bitmap to your Gallery Without Compress.

private File saveBitMap(Context context, Bitmap Final_bitmap) {
    File pictureFileDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "Your Folder Name");
    if (!pictureFileDir.exists()) {
        boolean isDirectoryCreated = pictureFileDir.mkdirs();
        if (!isDirectoryCreated)
            Log.i("TAG", "Can't create directory to save the image");
        return null;
    }
    String filename = pictureFileDir.getPath() + File.separator + System.currentTimeMillis() + ".jpg";
    File pictureFile = new File(filename);
    try {
        pictureFile.createNewFile();
        FileOutputStream oStream = new FileOutputStream(pictureFile);
        Final_bitmap.compress(Bitmap.CompressFormat.PNG, 100, oStream);
        oStream.flush();
        oStream.close();
        Toast.makeText(Full_Screen_Activity.this, "Save Image Successfully..", Toast.LENGTH_SHORT).show();
    } catch (IOException e) {
        e.printStackTrace();
        Log.i("TAG", "There was an issue saving the image.");
    }
    scanGallery(context, pictureFile.getAbsolutePath());
    return pictureFile;
}
private void scanGallery(Context cntx, String path) {
    try {
        MediaScannerConnection.scanFile(cntx, new String[]{path}, null, new MediaScannerConnection.OnScanCompletedListener() {
            public void onScanCompleted(String path, Uri uri) {
                Toast.makeText(Full_Screen_Activity.this, "Save Image Successfully..", Toast.LENGTH_SHORT).show();
            }
        });
    } catch (Exception e) {
        e.printStackTrace();
        Log.i("TAG", "There was an issue scanning gallery.");
    }
}

These two lines need to be in bracelet !!! Log.i("TAG", "Can't create directory to save the image"); return null;
H
Himanshu Rawat

You want to save Bitmap to Directory of your Choice. I have made a library ImageWorker that enables the user to load, save and convert bitmaps/drawables/base64 images.

Min SDK - 14

Pre-requisite

Saving files would require WRITE_EXTERNAL_STORAGE permission.

Retrieving files would require READ_EXTERNAL_STORAGE permission.

Saving Bitmap/Drawable/Base64

ImageWorker.to(context).
    directory("ImageWorker").
    subDirectory("SubDirectory").
    setFileName("Image").
    withExtension(Extension.PNG).
    save(sourceBitmap,85)

Loading Bitmap

val bitmap: Bitmap? = ImageWorker.from(context).
    directory("ImageWorker").
    subDirectory("SubDirectory").
    setFileName("Image").
    withExtension(Extension.PNG).
    load()

Implementation

Add Dependencies

In Project Level Gradle

allprojects {
        repositories {
            ...
            maven { url 'https://jitpack.io' }
        }
    }

In Application Level Gradle

dependencies {
            implementation 'com.github.ihimanshurawat:ImageWorker:0.51'
    }

You can read more on https://github.com/ihimanshurawat/ImageWorker/blob/master/README.md


m
mech

Make sure the directory is created before you call bitmap.compress:

new File(FileName.substring(0,FileName.lastIndexOf("/"))).mkdirs();

M
MashukKhan

Create a video thumbnail for a video. It may return null if the video is corrupted or the format is not supported.

private void makeVideoPreview() {
    Bitmap thumbnail = ThumbnailUtils.createVideoThumbnail(videoAbsolutePath, MediaStore.Images.Thumbnails.MINI_KIND);
    saveImage(thumbnail);
}

To Save your bitmap in sdcard use the following code

Store Image

private void storeImage(Bitmap image) {
    File pictureFile = getOutputMediaFile();
    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());
    }  
}

To Get the Path for Image Storage

/** Create a File for saving an image or video */
private  File getOutputMediaFile(){
    // To be safe, you should check that the SDCard is mounted
    // using Environment.getExternalStorageState() before doing this. 
    File mediaStorageDir = new File(Environment.getExternalStorageDirectory()
            + "/Android/data/"
            + getApplicationContext().getPackageName()
            + "/Files"); 

    // This location works best if you want the created images to be shared
    // between applications and persist after your app has been uninstalled.

    // Create the storage directory if it does not exist
    if (! mediaStorageDir.exists()){
        if (! mediaStorageDir.mkdirs()){
            return null;
        }
    } 
    // Create a media file name
    String timeStamp = new SimpleDateFormat("ddMMyyyy_HHmm").format(new Date());
    File mediaFile;
        String mImageName="MI_"+ timeStamp +".jpg";
        mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName);  
    return mediaFile;
} 

Z
Zar E Ahmer

Some new devices don't save bitmap So I explained a little more..

make sure you have added below Permission

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

and create a xml file under xml folder name provider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-path
        name="external_files"
        path="." />
</paths>

and in AndroidManifest under

<provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="${applicationId}.provider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"/>
        </provider>

then simply call saveBitmapFile(passYourBitmapHere)

public static void saveBitmapFile(Bitmap bitmap) throws IOException {
        File mediaFile = getOutputMediaFile();
        FileOutputStream fileOutputStream = new FileOutputStream(mediaFile);
        bitmap.compress(Bitmap.CompressFormat.JPEG, getQualityNumber(bitmap), fileOutputStream);
        fileOutputStream.flush();
        fileOutputStream.close();
    }

where

File getOutputMediaFile() {
        File mediaStorageDir = new File(
                Environment.getExternalStorageDirectory(),
                "easyTouchPro");
        if (mediaStorageDir.isDirectory()) {

            // Create a media file name
            String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
                    .format(Calendar.getInstance().getTime());
            String mCurrentPath = mediaStorageDir.getPath() + File.separator
                            + "IMG_" + timeStamp + ".jpg";
            File mediaFile = new File(mCurrentPath);
            return mediaFile;
        } else { /// error handling for PIE devices..
            mediaStorageDir.delete();
            mediaStorageDir.mkdirs();
            galleryAddPic(mediaStorageDir);

            return (getOutputMediaFile());
        }
    }

and other methods

public static int getQualityNumber(Bitmap bitmap) {
        int size = bitmap.getByteCount();
        int percentage = 0;

        if (size > 500000 && size <= 800000) {
            percentage = 15;
        } else if (size > 800000 && size <= 1000000) {
            percentage = 20;
        } else if (size > 1000000 && size <= 1500000) {
            percentage = 25;
        } else if (size > 1500000 && size <= 2500000) {
            percentage = 27;
        } else if (size > 2500000 && size <= 3500000) {
            percentage = 30;
        } else if (size > 3500000 && size <= 4000000) {
            percentage = 40;
        } else if (size > 4000000 && size <= 5000000) {
            percentage = 50;
        } else if (size > 5000000) {
            percentage = 75;
        }

        return percentage;
    }

and

void galleryAddPic(File f) {
        Intent mediaScanIntent = new Intent(
                "android.intent.action.MEDIA_SCANNER_SCAN_FILE");
        Uri contentUri = Uri.fromFile(f);
        mediaScanIntent.setData(contentUri);

        this.sendBroadcast(mediaScanIntent);
    }

Do you have some more information about error handling for PIE devices.. and I guess the recursion in getOutputMediaFile could be an infinite loop if the workaround fails.
M
Mayank Saini

Hey just give the name to .bmp

Do this:

ByteArrayOutputStream bytes = new ByteArrayOutputStream();
_bitmapScaled.compress(Bitmap.CompressFormat.PNG, 40, bytes);

//you can create a new file name "test.BMP" in sdcard folder.
File f = new File(Environment.getExternalStorageDirectory()
                        + File.separator + "**test.bmp**")

it'll sound that IM JUST FOOLING AROUND but try it once it'll get saved in bmp foramt..Cheers


T
Thracian

After Android 4.4 Kitkat, and as of 2017 share of Android 4.4 and less is about 20% and decreasing, it's not possible to save to SD card using File class and getExternalStorageDirectory() method. This method returns your device internal memory and images save visible to every app. You can also save images only private to your app and to be deleted when user deletes your app with openFileOutput() method.

Starting with Android 6.0, you can format your SD card as an internal memory but only private to your device.(If you format SD car as internal memory, only your device can access or see it's contents) You can save to that SD card using other answers but if you want to use a removable SD card you should read my answer below.

You should use Storage Access Framework to get uri to folder onActivityResult method of activity to get folder selected by user, and add retreive persistiable permission to be able to access folder after user restarts the device.

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (resultCode == RESULT_OK) {

        // selectDirectory() invoked
        if (requestCode == REQUEST_FOLDER_ACCESS) {

            if (data.getData() != null) {
                Uri treeUri = data.getData();
                tvSAF.setText("Dir: " + data.getData().toString());
                currentFolder = treeUri.toString();
                saveCurrentFolderToPrefs();

                // grantUriPermission(getPackageName(), treeUri,
                // Intent.FLAG_GRANT_READ_URI_PERMISSION |
                // Intent.FLAG_GRANT_WRITE_URI_PERMISSION);

                final int takeFlags = data.getFlags()
                        & (Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
                // Check for the freshest data.
                getContentResolver().takePersistableUriPermission(treeUri, takeFlags);

            }
        }
    }
}

Now, save save folder to shared preferences not to ask user to select folder every time you want to save an image.

You should use DocumentFile class to save your image, not File or ParcelFileDescriptor, for more info you can check this thread for saving image to SD card with compress(CompressFormat.JPEG, 100, out); method and DocumentFile classes.


S
Sujay U N

// |==| Create a PNG File from Bitmap :

void devImjFylFnc(String pthAndFylTtlVar, Bitmap iptBmjVar)
{
    try
    {
        FileOutputStream fylBytWrtrVar = new FileOutputStream(pthAndFylTtlVar);
        iptBmjVar.compress(Bitmap.CompressFormat.PNG, 100, fylBytWrtrVar);
        fylBytWrtrVar.close();
    }
    catch (Exception errVar) { errVar.printStackTrace(); }
}

// |==| Get Bimap from File :

Bitmap getBmjFrmFylFnc(String pthAndFylTtlVar)
{
    return BitmapFactory.decodeFile(pthAndFylTtlVar);
}