fn idct_col(blk: &mut [i16; 64], off: usize) {
let in0 = ((i32::from(blk[off + 0*8])) << 8) + (1 << (COL_SHIFT - 1));
let in1 = (i32::from(blk[off + 4*8])) << 8;
fn idct_col(blk: &mut [i16; 64], off: usize) {
let in0 = ((i32::from(blk[off + 0*8])) << 8) + (1 << (COL_SHIFT - 1));
let in1 = (i32::from(blk[off + 4*8])) << 8;