--- /dev/null
+use nihav_codec_support::codecs::{MV, ZERO_MV};
+
+pub fn pix_dist(a: u8, b: u8) -> u32 {
+ ((i32::from(a) - (i32::from(b))) * (i32::from(a) - (i32::from(b)))) as u32
+}
+
+pub fn calc_diff(src1: &[u8], stride1: usize, src2: &[u8], stride2: usize) -> u32 {
+ src1.chunks(stride1).zip(src2.chunks(stride2)).take(8).fold(0u32,
+ |acc, (line1, line2)| acc + line1[..8].iter().zip(line2.iter()).fold(0u32,
+ |acc2, (&a, &b)| acc2 + pix_dist(a, b)))
+}
+
+const DIA_LARGE: [MV; 4] = [MV{x: 2, y: 0}, MV{x: 0, y: 2}, MV{x: -2, y: 0}, MV{x: 0, y: -2}];
+const DIA_SMALL: [MV; 4] = [MV{x: 1, y: 0}, MV{x: 0, y: 1}, MV{x: -1, y: 0}, MV{x: 0, y: -1}];
+fn check_mv(x: usize, y: usize, width: usize, height: usize, mv: MV) -> bool {
+ let xpos = (x as isize) + isize::from(mv.x);
+ let ypos = (y as isize) + isize::from(mv.y);
+
+ mv.x.abs() <= 15 && mv.y.abs() <= 15 &&
+ xpos >= 0 && (xpos + 8 <= (width as isize)) &&
+ ypos >= 0 && (ypos + 8 <= (height as isize))
+}
+
+pub fn mv_search(src: &[u8], stride: usize, width: usize, height: usize,
+ x: usize, y: usize, skip_diff: u32,
+ ref_blk: &[u8; 64], tmp: &mut [u8; 64]) -> (MV, u32) {
+ let mut best_diff = skip_diff;
+ let mut best_mv = ZERO_MV;
+ loop {
+ let last_mv = best_mv;
+ for &off_mv in DIA_LARGE.iter() {
+ let mv = best_mv + off_mv;
+ if !check_mv(x, y, width, height, mv) {
+ continue;
+ }
+ get_block(src, stride, x, y, mv, tmp);
+ let diff = calc_diff(ref_blk, 8, tmp, 8);
+ if diff < best_diff {
+ best_diff = diff;
+ best_mv = mv;
+ }
+ }
+ if best_mv == last_mv {
+ break;
+ }
+ }
+ loop {
+ let last_mv = best_mv;
+ for &off_mv in DIA_SMALL.iter() {
+ let mv = best_mv + off_mv;
+ if !check_mv(x, y, width, height, mv) {
+ continue;
+ }
+ get_block(src, stride, x, y, mv, tmp);
+ let diff = calc_diff(ref_blk, 8, tmp, 8);
+ if diff < best_diff {
+ best_diff = diff;
+ best_mv = mv;
+ }
+ }
+ if best_mv == last_mv {
+ break;
+ }
+ }
+ (best_mv, best_diff)
+}
+
+pub fn get_block(src: &[u8], stride: usize, x: usize, y: usize, mv: MV, dst: &mut [u8; 64]) {
+ let pos = (x as isize + isize::from(mv.x) + (y as isize + isize::from(mv.y)) * (stride as isize)) as usize;
+ for (dline, sline) in dst.chunks_exact_mut(8).zip(src[pos..].chunks(stride)) {
+ dline.copy_from_slice(&sline[..8]);
+ }
+}
+
+pub fn put_block(dst: &mut [u8], dstride: usize, cur_blk: &[u8; 64]) {
+ for (dline, sline) in dst.chunks_mut(dstride).zip(cur_blk.chunks_exact(8)) {
+ dline[..8].copy_from_slice(sline);
+ }
+}