What's an efficient way to tell if a bitmap is entirely black?

Question

I\'m wondering if there\'s a super-efficient way of confirming that an Image object references an entirely black image, so every pixel within the bitmap is ARGB(255, 0, 0, 0).

Answer 1

    private bool AllOneColor(Bitmap bmp)
    {
        BitmapData bmpData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadOnly, PixelFormat.Format8bppIndexed);
        byte[] rgbValues = new byte[bmpData.Stride * bmpData.Height];
        System.Runtime.InteropServices.Marshal.Copy(bmpData.Scan0, rgbValues, 0, rgbValues.Length);
        bmp.UnlockBits(bmpData);
        return !rgbValues.Where((v, i) => i % bmpData.Stride < bmp.Width && v != rgbValues[0]).Any();
    }