Trying to loop through all pixels in a bmp with arduino

Projects Programming
5

I do not understand

Bitmap bmp = new Bitmap("SomeImage");

// Lock the bitmap's bits.
Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
BitmapData bmpData = bmp.LockBits(rect, ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);

// Get the address of the first line.
IntPtr ptr = bmpData.Scan0;

// Declare an array to hold the bytes of the bitmap.
int bytes = bmpData.Stride * bmp.Height

I don't know how to replace lock bmp.lockbits or stride
The Bitmap class with all of these comes from .Net framework. Does anyone know similar classes?