for i in 0..self.ncomps {
dst[offs[i] + x] = convert_depth((elem >> self.shifts[i]) & self.masks[i], self.depths[i], self.osize[i]) as u8;
}
for i in 0..self.ncomps {
dst[offs[i] + x] = convert_depth((elem >> self.shifts[i]) & self.masks[i], self.depths[i], self.osize[i]) as u8;
}