How to change color qr generating to another color of black

Question

I working in visual studio 2015 windows form application

 

I generating qr using messagetoolkit library and it working good without any problem

 

I face only one problem i need to change color of qr to another color different to

 

black as blue or red or green like that

 

so that how to do color qr code using messagetoolkit

 

my code

MessagingToolkit.QRCode.Codec.QRCodeEncoder encoder = new MessagingToolkit.QRCode.Codec.QRCodeEncoder();
                   encoder.QRCodeScale = 8;
                   Bitmap bmp = encoder.Encode(textBox1.Text);
                   pictureBox1.Image = bmp;
                   bmp.Save(sv.FileName, ImageFormat.Jpeg);