 		const int x_4 = 4 * (blockIdx.x * blockDim.x + threadIdx.x);
 		const int y = blockIdx.y * blockDim.y + threadIdx.y;
 
-		if (h < RADIUS || y >= h - RADIUS)
+		if (y < RADIUS || y >= h - RADIUS)
 			return;
 
 		uint32_t buf[KSIZE_SQ];

		const int x_2 = 2 * (blockIdx.x * blockDim.x + threadIdx.x);
		const int y = blockIdx.y * blockDim.y + threadIdx.y;

		if (h < RADIUS || y >= h - RADIUS)
			return;

		uint32_t buf[KSIZE_SQ];

	{
		const int x = blockIdx.x * blockDim.x + threadIdx.x;
		const int y = blockIdx.y * blockDim.y + threadIdx.y;
		if (x < RADIUS || x >= w - RADIUS || y < RADIUS || y >= h - RADIUS)
			return;

		uint16_t buf[KSIZE_SQ];
