How to reduce an Image file size before uploading to a server

Question

Lot of application allow sharing an image, which is picked from the gallery.

Do they upload the original image file? Which is like 1-3 mb? Or do they process?

In any case, how can I take the image from a filepath, reduce its size by lowering the resolution and save it some where else and the try to upload?

I tried:

Bitmap photo = decodeSampledBitmapFromFile(filePath, DESIRED_WIDTH,
                    DESIRED_HEIGHT);

FileOutputStream out = new FileOutputStream(filePath);
photo.compress(Bitmap.CompressFormat.JPEG, 100, out);

public static Bitmap decodeSampledBitmapFromFile(String path, int reqWidth,
        int reqHeight) {

    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(path, options);

    final int height = options.outHeight;
    final int width = options.outWidth;
    options.inPreferredConfig = Bitmap.Config.ARGB_8888;
    int inSampleSize = 1;

    if (height > reqHeight) {
        inSampleSize = Math.round((float) height / (float) reqHeight);
    }
    int expectedWidth = width / inSampleSize;

    if (expectedWidth > reqWidth) {
        inSampleSize = Math.round((float) width / (float) reqWidth);
    }
    options.inSampleSize = inSampleSize;
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeFile(path, options);
}

But is this they right way to do? Because I have seen answers suggesting compression operation takes rather big amount of time here

Solution 1

I use this function to reduce the size of image before uploading it, it reduces the image size to nearly 200 KB and keep the quality relatively good, u may modify it to fulfill your purpose by changing the REQUIRED_SIZE and inSampleSize:

public File saveBitmapToFile(File file){
    try {

        // BitmapFactory options to downsize the image
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        o.inSampleSize = 6;
        // factor of downsizing the image

        FileInputStream inputStream = new FileInputStream(file);
        //Bitmap selectedBitmap = null;
        BitmapFactory.decodeStream(inputStream, null, o);
        inputStream.close();

        // The new size we want to scale to
        final int REQUIRED_SIZE=75;

        // Find the correct scale value. It should be the power of 2.
        int scale = 1;
        while(o.outWidth / scale / 2 >= REQUIRED_SIZE &&
                        o.outHeight / scale / 2 >= REQUIRED_SIZE) {
            scale *= 2;
        }

        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        inputStream = new FileInputStream(file);

        Bitmap selectedBitmap = BitmapFactory.decodeStream(inputStream, null, o2);
        inputStream.close();

        // here i override the original image file
        file.createNewFile();
        FileOutputStream outputStream = new FileOutputStream(file);

        selectedBitmap.compress(Bitmap.CompressFormat.JPEG, 100 , outputStream);

        return file;
    } catch (Exception e) {
        return null;
    }
}

NOTE: I resize and override the original file image in this function, u may write it to another file as well.

I hope it may help you.

Solution 2

This is working great Try this

private String decodeFile(String path,int DESIREDWIDTH, int DESIREDHEIGHT) {
        String strMyImagePath = null;
        Bitmap scaledBitmap = null;

        try {
            // Part 1: Decode image
            Bitmap unscaledBitmap = ScalingUtilities.decodeFile(path, DESIREDWIDTH, DESIREDHEIGHT, ScalingLogic.FIT);

            if (!(unscaledBitmap.getWidth() <= DESIREDWIDTH && unscaledBitmap.getHeight() <= DESIREDHEIGHT)) {
                // Part 2: Scale image
                scaledBitmap = ScalingUtilities.createScaledBitmap(unscaledBitmap, DESIREDWIDTH, DESIREDHEIGHT, ScalingLogic.FIT);
            } else {
                unscaledBitmap.recycle();
                return path;
            }

            // Store to tmp file

            String extr = Environment.getExternalStorageDirectory().toString();
            File mFolder = new File(extr + "/TMMFOLDER");
            if (!mFolder.exists()) {
                mFolder.mkdir();
            }

            String s = "tmp.png";

            File f = new File(mFolder.getAbsolutePath(), s);

            strMyImagePath = f.getAbsolutePath();
            FileOutputStream fos = null;
            try {
                fos = new FileOutputStream(f);
                scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 75, fos);
                fos.flush();
                fos.close();
            } catch (FileNotFoundException e) {

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

                e.printStackTrace();
            }

            scaledBitmap.recycle();
        } catch (Throwable e) {
        }

        if (strMyImagePath == null) {
            return path;
        }
        return strMyImagePath;

    }

ScalingUtilities.java

import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.BitmapFactory.Options;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;

/**
 * Class containing static utility methods for bitmap decoding and scaling
 *
 * @author 
 */
public class ScalingUtilities {

    /**
     * Utility function for decoding an image resource. The decoded bitmap will
     * be optimized for further scaling to the requested destination dimensions
     * and scaling logic.
     *
     * @param res The resources object containing the image data
     * @param resId The resource id of the image data
     * @param dstWidth Width of destination area
     * @param dstHeight Height of destination area
     * @param scalingLogic Logic to use to avoid image stretching
     * @return Decoded bitmap
     */
    public static Bitmap decodeResource(Resources res, int resId, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        Options options = new Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(res, resId, options);
        options.inJustDecodeBounds = false;
        options.inSampleSize = calculateSampleSize(options.outWidth, options.outHeight, dstWidth,
                dstHeight, scalingLogic);
        Bitmap unscaledBitmap = BitmapFactory.decodeResource(res, resId, options);

        return unscaledBitmap;
    }
    public static Bitmap decodeFile(String path, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        Options options = new Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(path, options);
        options.inJustDecodeBounds = false;
        options.inSampleSize = calculateSampleSize(options.outWidth, options.outHeight, dstWidth,
                dstHeight, scalingLogic);
        Bitmap unscaledBitmap = BitmapFactory.decodeFile(path, options);

        return unscaledBitmap;
    }

    /**
     * Utility function for creating a scaled version of an existing bitmap
     *
     * @param unscaledBitmap Bitmap to scale
     * @param dstWidth Wanted width of destination bitmap
     * @param dstHeight Wanted height of destination bitmap
     * @param scalingLogic Logic to use to avoid image stretching
     * @return New scaled bitmap object
     */
    public static Bitmap createScaledBitmap(Bitmap unscaledBitmap, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        Rect srcRect = calculateSrcRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Rect dstRect = calculateDstRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Bitmap scaledBitmap = Bitmap.createBitmap(dstRect.width(), dstRect.height(),
                Config.ARGB_8888);
        Canvas canvas = new Canvas(scaledBitmap);
        canvas.drawBitmap(unscaledBitmap, srcRect, dstRect, new Paint(Paint.FILTER_BITMAP_FLAG));

        return scaledBitmap;
    }

    /**
     * ScalingLogic defines how scaling should be carried out if source and
     * destination image has different aspect ratio.
     *
     * CROP: Scales the image the minimum amount while making sure that at least
     * one of the two dimensions fit inside the requested destination area.
     * Parts of the source image will be cropped to realize this.
     *
     * FIT: Scales the image the minimum amount while making sure both
     * dimensions fit inside the requested destination area. The resulting
     * destination dimensions might be adjusted to a smaller size than
     * requested.
     */
    public static enum ScalingLogic {
        CROP, FIT
    }

    /**
     * Calculate optimal down-sampling factor given the dimensions of a source
     * image, the dimensions of a destination area and a scaling logic.
     *
     * @param srcWidth Width of source image
     * @param srcHeight Height of source image
     * @param dstWidth Width of destination area
     * @param dstHeight Height of destination area
     * @param scalingLogic Logic to use to avoid image stretching
     * @return Optimal down scaling sample size for decoding
     */
    public static int calculateSampleSize(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcWidth / dstWidth;
            } else {
                return srcHeight / dstHeight;
            }
        } else {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcHeight / dstHeight;
            } else {
                return srcWidth / dstWidth;
            }
        }
    }

    /**
     * Calculates source rectangle for scaling bitmap
     *
     * @param srcWidth Width of source image
     * @param srcHeight Height of source image
     * @param dstWidth Width of destination area
     * @param dstHeight Height of destination area
     * @param scalingLogic Logic to use to avoid image stretching
     * @return Optimal source rectangle
     */
    public static Rect calculateSrcRect(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.CROP) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                final int srcRectWidth = (int)(srcHeight * dstAspect);
                final int srcRectLeft = (srcWidth - srcRectWidth) / 2;
                return new Rect(srcRectLeft, 0, srcRectLeft + srcRectWidth, srcHeight);
            } else {
                final int srcRectHeight = (int)(srcWidth / dstAspect);
                final int scrRectTop = (int)(srcHeight - srcRectHeight) / 2;
                return new Rect(0, scrRectTop, srcWidth, scrRectTop + srcRectHeight);
            }
        } else {
            return new Rect(0, 0, srcWidth, srcHeight);
        }
    }

    /**
     * Calculates destination rectangle for scaling bitmap
     *
     * @param srcWidth Width of source image
     * @param srcHeight Height of source image
     * @param dstWidth Width of destination area
     * @param dstHeight Height of destination area
     * @param scalingLogic Logic to use to avoid image stretching
     * @return Optimal destination rectangle
     */
    public static Rect calculateDstRect(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return new Rect(0, 0, dstWidth, (int)(dstWidth / srcAspect));
            } else {
                return new Rect(0, 0, (int)(dstHeight * srcAspect), dstHeight);
            }
        } else {
            return new Rect(0, 0, dstWidth, dstHeight);
        }
    }

}

Solution 3

Here's a solution that's handled in memory and doesn't require actually generating a file on the file system.

From some Fragment, after user selects an image file:

@Override
public void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) {
    super.onActivityResult(requestCode, resultCode, imageReturnedIntent);

    if (imageReturnedIntent == null
            || imageReturnedIntent.getData() == null) {
        return;
    }

    // aiming for ~500kb max. assumes typical device image size is around 2megs
    int scaleDivider = 4; 


    try {

        // 1. Convert uri to bitmap
        Uri imageUri = imageReturnedIntent.getData();
        Bitmap fullBitmap = MediaStore.Images.Media.getBitmap(getActivity().getContentResolver(), imageUri);

        // 2. Get the downsized image content as a byte[]
        int scaleWidth = fullBitmap.getWidth() / scaleDivider;
        int scaleHeight = fullBitmap.getHeight() / scaleDivider;
        byte[] downsizedImageBytes =
                getDownsizedImageBytes(fullBitmap, scaleWidth, scaleHeight);

        // 3. Upload the byte[]; Eg, if you are using Firebase
        StorageReference storageReference =
                FirebaseStorage.getInstance().getReference("/somepath");

        storageReference.putBytes(downsizedImageBytes);
    }
    catch (IOException ioEx) {
        ioEx.printStackTrace();
    }
}

public byte[] getDownsizedImageBytes(Bitmap fullBitmap, int scaleWidth, int scaleHeight) throws IOException {

    Bitmap scaledBitmap = Bitmap.createScaledBitmap(fullBitmap, scaleWidth, scaleHeight, true);

    // 2. Instantiate the downsized image content as a byte[]
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
    byte[] downsizedImageBytes = baos.toByteArray();

    return downsizedImageBytes;
}

Thanks to:

• Convert uri to bitmap: https://stackoverflow.com/a/4717740/2162226
• Scaling/resize step (from this thread): https://stackoverflow.com/a/50192169/2162226
• Save byte[] to Firebase : https://stackoverflow.com/a/40886397/2162226

Solution 4

this code reduce size image

private Bitmap compressImage(Bitmap image) {

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        image.compress(Bitmap.CompressFormat.JPEG, 100, baos);//Compression quality, here 100 means no compression, the storage of compressed data to baos
        int options = 90;
        while (baos.toByteArray().length / 1024 > 400) {  //Loop if compressed picture is greater than 400kb, than to compression
            baos.reset();//Reset baos is empty baos
            image.compress(Bitmap.CompressFormat.JPEG, options, baos);//The compression options%, storing the compressed data to the baos
            options -= 10;//Every time reduced by 10
        }
        ByteArrayInputStream isBm = new ByteArrayInputStream(baos.toByteArray());//The storage of compressed data in the baos to ByteArrayInputStream
        Bitmap bitmap = BitmapFactory.decodeStream(isBm, null, null);//The ByteArrayInputStream data generation
        return bitmap;
    }

Solution 5

You can use this library named Compressor.

Compress Image File

val compressedImageFile = Compressor.compress(context, actualImageFile)
Compress Image File to specific destination
val compressedImageFile = Compressor.compress(context, actualImageFile) {
    default()
    destination(myFile)
}

Custom Compressor

Using default constraint and custom partial of it

  val compressedImageFile = 
       Compressor.compress(context, actualImageFile) {
        default(width = 640, format = Bitmap.CompressFormat.WEBP)
    }

Full custom constraint

val compressedImageFile = Compressor.compress(context, actualImageFile) {
    resolution(1280, 720)
    quality(80)
    format(Bitmap.CompressFormat.WEBP)
    size(2_097_152) // 2 MB
}

Using own custom constraint

class MyLowerCaseNameConstraint: Constraint {
    override fun isSatisfied(imageFile: File): Boolean {
        return imageFile.name.all { it.isLowerCase() }
    }

    override fun satisfy(imageFile: File): File {
        val destination = File(imageFile.parent, imageFile.name.toLowerCase())
        imageFile.renameTo(destination)
        return destination
    }
}

val compressedImageFile = Compressor.compress(context, actualImageFile) {
    constraint(MyLowerCaseNameConstraint()) // your own constraint
    quality(80) // combine with compressor constraint
    format(Bitmap.CompressFormat.WEBP)
}

Create Kotlin extension -

fun Compression.lowerCaseName() {
    constraint(MyLowerCaseNameConstraint())
}

val compressedImageFile = Compressor.compress(context, actualImageFile) {
    lowerCaseName() // your own extension
    quality(80) // combine with compressor constraint
    format(Bitmap.CompressFormat.WEBP)
}

Compress image with Kotlin coroutines -

// e.g calling from activity lifecycle scope
lifecycleScope.launch {
    val compressedImageFile = Compressor.compress(context, actualImageFile)
}

// calling from global scope
GlobalScope.launch {
    val compressedImageFile = Compressor.compress(context, actualImageFile)
}

Run Compressor in main thread -

val compressedImageFile = Compressor.compress(context, actualImageFile, Dispatchers.Main)

View more solutions

Comments

[Arun Badole]

Really useful Answer.

[Syed Raza Mehdi]

this didn't help, how to use this?

[Däñish Shärmà]

thanks alot. This is the only answer which worked for me.

[Logain]

You are compressing the image as JPEG but naming it with ".png" extension. Not that it actually matters anyway... but still

[Kishan Vaghela]

follow this if you got OutOfMemory

[Gaurav Sarma]

Where is the getOrientation method implementation ?

[Akshay Kumar]

@Biraj Zalavadia Where and how to call this ------------------

[Akshay Kumar]

@MBH How to all this method and where i will get the file argument from

[MBH]

@AkshayKumar the parameter file, will be the file that you will write to. new File("your_image_to_be_comopressed_full_path");. The output file is the same file if successfully done. Null if something went wrong. NOTICE that to not override the existing image, remove the line file.createNewFile(); and write the image to another file instead.

[codeKiller]

getOrientation is missing

[Usman Rana]

what is REQUIRED_SIZE ? is it percentage of scaling or fixed dimen of output image?

[reetu]

@Biraj Zalavadia I am trying to use this code, but getting null on unscaledBitmap any idea why it might return null.

[SlimenTN]

Your method is great but I don't know why it's rotating the image !!! I get a rotated image after reducing it's size using this function !!

[Mohammedsalim Shivani]

Please add all the required/depended methods in the answer.

[Tim Cooper]

There are a lot of file operations here.

[San Juan]

I don't understand what you mean

[Tim Cooper]

There is a loop and you potentially write the image to the file-system multiple times, once for each iteration in the loop. Could it be done in memory instead? I think the file will be approx. 1/4 the size each iteration so it's not a big deal. I think your method will work and I did something similar but without a loop.

[San Juan]

@TimCooper Where can I find your solution?

[mehdi]

this solution has low performance because of calling compress method several times.

[Mabz]

@reetu I got the message too and I suspect it is because I am using the Uri.getPath() operation to get the filename.

[Acheme Paul]

Works well, clean and nice

[Nainal]

@MBH what should be the REQUIRED_SIZE for image size upto 4MB?

[MBH]

@Nainal it’s been a while and i forgot the code i wrote :( you may checkout by testing anyway :)

[Awadesh]

how can we define int DESIREDWIDTH, int DESIREDHEIGHT, I have to maintain the image originality and show on different devices, please help

[HendraWD]

I think you should think of cleanup mechanism of your temporary image and folder. It will be better if the folder using cache/data folder of the application.

[varun]

@MBH I can't say if those are sad and happy ASCII emoticons or just parentheses preceded by a colon... hmmmmmmm... xD

[varun]

Ah yes, it works elegantly. For some reason, using image.compress(Bitmap.CompressFormat.FORMAT, QUALITY, fileOutputStream) did not work. However, your solution which uses the BitmapFactory produces 8x size reduction without compromising quality! Thanks!

[Gene Bo]

This answer was helpful in understanding the code nec. for image scaling, which helped me put together the answer I posted here as well. In case it helps - the part that didn't work for me is that the final Bitmap bitmap was still the same size as the original input Bitmap image

[mazend]

Goon answer but.. am I the only one who think the function name is not appropriate?

[MBH]

@mazend You are right, you are free to edit my answer and put a better name :)

[Thiago Silva]

It helped me to complete my code as it comes with great insights like the max size and other things. Its really very helpfull although its not a complete code.

[Ast]

MBH as @Slimen says if I take a picture in protrait mode, it is rotated...but I can't understand why

[Androidz]

Nice solution! I recommend just adding size check and setting scaleDivider based on this value as images very a lot are not constant on 2MB!

[adegolyer]

For those with rotation problems: You can get image orientation from the originals exif data and write it to the copy.

[PERAM BRAHMA REDDY]

private ImageCodecInfo GetEncoder(ImageFormat format) { /*/ Hope this will work.Thanks in advance /*/ ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders(); foreach (ImageCodecInfo codec in codecs) { if (codec.FormatID == format.Guid) { return codec; } } return null; }

[Fattie]

Thanks so much GeneBo! This is like a top-100 answer on the entire site, buried here in obscurity. Sending a token bounty, thanks. I was just wondering, for completeness could U add a line preserving exif data (for us iOS programmers passing by :) ) Gene ROCKS !! what an awesome answer.

[Gene Bo]

Thanks for the kind word :) . exif data is outside my range. This search seemed to turn up some answers on SO: image preserving exif data android .. opting for Android to follow w/this answer. Perhaps you see a way to tie one of those in here?

[Fattie]

Got it. @GeneBo I sent a small bounty to say thanks - cheers

[Gene Bo]

Hi @Fattie, always good to hear an answer on SO helps someone, but wow what an unexpected surprise I found when checking back in after the weekend. That's very generous of you. You replenished the bounties I've given out in the last year - pretty cool, I appreciate it. And with your strong rank here, I take the gesture as a compliment .. no joke, Thank you

[Emon Hossain Munna]

Hey Emon Thanks Mate! Its Your Friend Of Friends (Habib UITS)

[Gk Mohammad Emon]

Hi @EmonHossainMunna , Nice to meet you. See you soon.

[KJEjava48]

@GeneBo Can we choose any compression format instead of Bitmap.CompressFormat.JPEG ?? Does this should be the same of the actual file ??

[Bita Mirshafiee]

for image rotation problem, do this: val oldExif = ExifInterface(file.path) val exifOrientation = oldExif.getAttribute(ExifInterface.TAG_ORIENTATION) if (exifOrientation != null) { val newExif = ExifInterface(file.path) newExif.setAttribute(ExifInterface.TAG_ORIENTATION, exifOrientation) newExif.saveAttributes() }