Custom bitmap object isn't displaying correctly in PictureBox

Question

I'm trying to generate a custom Bitmap through code at a very small size and display it to a PictureBox, upscaled to fit said PictureBox. I am using the graphics object to do this in order to use NearestNeighbor interpolation to upscale single pixels perfectly.

I'm using the graphics object of a temporary default image that is in the PictureBoxs "Image" component on Form.Load, which is sized to be the perfect width and height to maintain the correct aspect ratio from the original Bitmap.

Here is the relevant code:

private void Form1_Load(object sender, EventArgs e)
{
    bmp = new Bitmap(16, 9, PixelFormat.Format24bppRgb);
    rnd = new Random();

    GenerateImage();
}

private void GenerateImage()
{
    for (int x = 0; x < bmp.Width; x++)
    {
        for (int y = 0; y < bmp.Height; y++)
        {
            int num = rnd.Next(2);
            if (num == 0)
            {
                bmp.SetPixel(x, y, Color.White);
            }
            else
            {
                bmp.SetPixel(x, y, Color.Gold);
            }
        }
    }

    Bitmap image = new Bitmap(picOutput.Image);
    grp = Graphics.FromImage(image);

    grp.InterpolationMode = InterpolationMode.NearestNeighbor;

    grp.DrawImage(
        bmp,
        new Rectangle(0, 0, image.Width, image.Height),
        0,
        0,
        bmp.Width,
        bmp.Height,
        GraphicsUnit.Pixel
    );

    grp.Dispose();
    picOutput.Image = image;
}

The problem is that the Bitmap seems to be drawn incorrectly. About half a pixel from the original Bitmap is cut off on the left and top edges of the Bitmap when displayed through the PictureBox, and that roughly half a pixel shows up as the original default image on the right and bottom edges. It's almost like the Bitmap was offset up and to the left while being drawn by the graphics object, it doesn't perfectly cover up the original default image like it was supposed to.

My first thought was the PictureBoxs SizeMode, which is still set to "Normal," but none of them change the problem at all. Here is a picture of the problem. The black edges on the right and bottom are part of the temporary default image (the image I used graphics from), which is completely black and covers the entire PictureBox area.

Can anyone offer some insight?

Answer 1

As user Jimi pointed out in a comment, grp.PixelOffsetMode = PixelOffsetMode.Half from this post solved the issue.