Samsung introduced pixel-merging technologies such as Tetrapixel, and these enabled the mobile image sensors to reproduce colors properly depend on light conditions. High resolution image can be acquired when in well-lit area, by reorganize colors on the color filter array to RGB Bayer pattern. The aforementioned process is called remosaic algorithm, based on estimating direction information. It causes some artifacts on edges with various or unclear direction, for example in text-image, especially at high spatial frequencies. We focused on such artifacts caused by remosaicing, and proposed suitable image quality metric that can measure a degree of the artifacts.