Xamarin Forms - Resize Camera Picture

Question

Someone helped me get this code for taking a picture using xamarin forms labs camera:

picker = DependencyService.Get ();  
                       


        

Answer 1

@Sten's answer might encounter out-of-memory problem on some android devices. Here's my solution to implement the ResizeImage function , which is according to google's "Loading Large Bitmaps Efficiently" document:

public void ResizeImage (string sourceFile, string targetFile, int reqWidth, int reqHeight)
{ 
    if (!File.Exists (targetFile) && File.Exists (sourceFile)) {   
        var downImg = decodeSampledBitmapFromFile (sourceFile, reqWidth, reqHeight);
        using (var outStream = File.Create (targetFile)) {
            if (targetFile.ToLower ().EndsWith ("png"))
                downImg.Compress (Bitmap.CompressFormat.Png, 100, outStream);
            else
                downImg.Compress (Bitmap.CompressFormat.Jpeg, 95, outStream);
        }
        downImg.Recycle();
    }
}

public static Bitmap decodeSampledBitmapFromFile (string path, int reqWidth, int reqHeight)
{
    // First decode with inJustDecodeBounds=true to check dimensions
    var options = new BitmapFactory.Options ();
    options.InJustDecodeBounds = true;
    BitmapFactory.DecodeFile (path, options);

    // Calculate inSampleSize
    options.InSampleSize = calculateInSampleSize (options, reqWidth, reqHeight);

    // Decode bitmap with inSampleSize set
    options.InJustDecodeBounds = false;
    return BitmapFactory.DecodeFile (path, options);
}

public static int calculateInSampleSize (BitmapFactory.Options options, int reqWidth, int reqHeight)
{
    // Raw height and width of image
    int height = options.OutHeight;
    int width = options.OutWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {
        int halfHeight = height / 2;
        int halfWidth = width / 2;

        // Calculate the largest inSampleSize value that is a power of 2 and keeps both
        // height and width larger than the requested height and width.
        while ((halfHeight / inSampleSize) > reqHeight
               && (halfWidth / inSampleSize) > reqWidth) {
            inSampleSize *= 2;
        }
    }

    return inSampleSize;
}