To calculate the actual pixel at location (0,0) all neighboring Green and Blue values are used to predict what the correct RGB value should be in the R location.
The programmers of IQRaw where lazy, ignorant or both. Instead of applying one of the well known sophisticated algorithms, they decided to apply the same RGB pixel value FOR ALL 4 pixels in the Bayer 2×2 square.
Effectively this brings the photo resolution from 4000×3000 to 2000×1500. WTF – Come one guys…!