Code:

public static Bitmap scaleDown(Bitmap realImage, float maxImageSize,
        boolean filter) {
    float ratio = Math.min(
            (float) maxImageSize / realImage.getWidth(),
            (float) maxImageSize / realImage.getHeight());
    int width = Math.round((float) ratio * realImage.getWidth());
    int height = Math.round((float) ratio * realImage.getHeight());

    Bitmap newBitmap = Bitmap.createScaledBitmap(realImage, width,
            height, filter);
    return newBitmap;
}

***********************************************

Bitmap yourBitmap;
 Bitmap resized = Bitmap.createScaledBitmap(yourBitmap, newWidth, newHeight, true);

*************************************************

public static Bitmap scaleBitmap(Bitmap bitmap, int wantedWidth, int wantedHeight) {
        Bitmap output = Bitmap.createBitmap(wantedWidth, wantedHeight, Config.ARGB_8888);
        Canvas canvas = new Canvas(output);
        Matrix m = new Matrix();
        m.setScale((float) wantedWidth / bitmap.getWidth(), (float) wantedHeight / bitmap.getHeight());
        canvas.drawBitmap(bitmap, m, new Paint());

        return output;
    }

****************************************

public static Bitmap scaleBitmap(Bitmap bitmap, int wantedWidth, int wantedHeight) {
        Bitmap output = Bitmap.createBitmap(wantedWidth, wantedHeight, Config.ARGB_8888);
        Canvas canvas = new Canvas(output);
        Matrix m = new Matrix();
        m.setScale((float) wantedWidth / bitmap.getWidth(), (float) wantedHeight / bitmap.getHeight());
        canvas.drawBitmap(bitmap, m, new Paint());

        return output;
    }

**************************

public static Bitmap scaleDown(Bitmap realImage, float maxImageSize,
        boolean filter) {
    float ratio = Math.min(
            (float) maxImageSize / realImage.getWidth(),
            (float) maxImageSize / realImage.getHeight());
    int width = Math.round((float) ratio * realImage.getWidth());
    int height = Math.round((float) ratio * realImage.getHeight());

    Bitmap newBitmap = Bitmap.createScaledBitmap(realImage, width,
            height, filter);
    return newBitmap;
}

*****************************

public static Bitmap ScaleDownBitmap(Bitmap originalImage, float maxImageSize, bool filter)
    {
        float ratio = Math.Min((float)maxImageSize / originalImage.Width, (float)maxImageSize / originalImage.Height);
        int width = (int)Math.Round(ratio * (float)originalImage.Width);
        int height =(int) Math.Round(ratio * (float)originalImage.Height);

        Bitmap newBitmap = Bitmap.CreateScaledBitmap(originalImage, width, height, filter);
        return newBitmap;
    }

    public static Bitmap ScaleBitmap(Bitmap originalImage, int wantedWidth, int wantedHeight)
    {
        Bitmap output = Bitmap.CreateBitmap(wantedWidth, wantedHeight, Bitmap.Config.Argb8888);
        Canvas canvas = new Canvas(output);
        Matrix m = new Matrix();
        m.SetScale((float)wantedWidth / originalImage.Width, (float)wantedHeight / originalImage.Height);
        canvas.DrawBitmap(originalImage, m, new Paint());
        return output;
    }

}

*************************

private Bitmap scale(Bitmap bitmap, int maxWidth, int maxHeight) {
        // Determine the constrained dimension, which determines both dimensions.
        int width;
        int height;
        float widthRatio = (float)bitmap.getWidth() / maxWidth;
        float heightRatio = (float)bitmap.getHeight() / maxHeight;
        // Width constrained.
        if (widthRatio >= heightRatio) {
            width = maxWidth;
            height = (int)(((float)width / bitmap.getWidth()) * bitmap.getHeight());
        }
        // Height constrained.
        else {
            height = maxHeight;
            width = (int)(((float)height / bitmap.getHeight()) * bitmap.getWidth());
        }
        Bitmap scaledBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);

        float ratioX = (float)width / bitmap.getWidth();
        float ratioY = (float)height / bitmap.getHeight();
        float middleX = width / 2.0f;
        float middleY = height / 2.0f;
        Matrix scaleMatrix = new Matrix();
        scaleMatrix.setScale(ratioX, ratioY, middleX, middleY);

        Canvas canvas = new Canvas(scaledBitmap);
        canvas.setMatrix(scaleMatrix);
        canvas.drawBitmap(bitmap, middleX - bitmap.getWidth() / 2, middleY - bitmap.getHeight() / 2, new Paint(Paint.FILTER_BITMAP_FLAG));
        return scaledBitmap;
    }


java android studio scaling down a bitmap image

:hkn: