Why Does Saving A Loaded Bitmap Increase It's Size?

I load a png file from the sdcard. I alter it in someway and then save it again. I have noticed that the saved file is much larger than the original. At first I thought it was beca

Solution 1:

You can control the size of your Bitmap by the compress factor (quality):

Bitmap.compress(Bitmap.CompressFormat format, int quality, FileOutputStream out);

100 = maximum quality, 0 = low quality.

Try like "10" or something to keep your image smaller. It could also be that you are loading a Bitmap that is in 16-Bit color and than later save it in 32-Bit color, increasing its size.

Check BitmapConfig.RGB_565, BitmapConfig.ARGB_4444 and BitmapConfig.ARGB_8888 respectively.

EDIT:

Here is how to load Bitmaps correctly:

publicabstractclassBitmapResLoader {

    publicstatic Bitmap decodeBitmapFromResource(Bitmap.Config config, Resources res, int resId, int reqWidth, int reqHeight) {

        final BitmapFactory.Optionsoptions=newBitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(res, resId, options);

        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        options.inPreferredConfig = config;

        return BitmapFactory.decodeResource(res, resId, options);
    }

    privatestaticintcalculateInSampleSize(
                BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of imagefinalintheight= options.outHeight;
        finalintwidth= options.outWidth;
        intinSampleSize=1;

        if (height > reqHeight || width > reqWidth) {

            // Calculate ratios of height and width to requested height and widthfinalintheightRatio= Math.round((float) height / (float) reqHeight);
            finalintwidthRatio= Math.round((float) width / (float) reqWidth);

            // Choose the smallest ratio as inSampleSize value, this will guarantee// a final image with both dimensions larger than or equal to the// requested height and width.
            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
        }

        return inSampleSize;
    }
}

In code:

// Bitmap.Config.RGB_565 = 16 BitBitmapb= BitmapResLoader.decodeBitmapFromResource(Bitmap.Config.RGB_565, getResources(), width, height);

That way, you can control how your Bitmap is loaded into Memory (see Bitmap.Config).