From: Kostya Shishkov <kostya.shishkov@gmail.com>
Date: Wed, 27 Jul 2022 08:29:36 +0000 (+0200)
Subject: h264: fix direct 8x8 inference mode
X-Git-Url: https://git.nihav.org/?a=commitdiff_plain;h=d85f94f7fd0c00c63c33b3bc1dcf2640ec6bd52c;p=nihav.git

h264: fix direct 8x8 inference mode
---

diff --git a/nihav-itu/src/codecs/h264/mod.rs b/nihav-itu/src/codecs/h264/mod.rs
index 59fec0c..67156da 100644
--- a/nihav-itu/src/codecs/h264/mod.rs
+++ b/nihav-itu/src/codecs/h264/mod.rs
@@ -448,14 +448,14 @@ println!("PAFF?");
 
         Ok(())
     }
-    fn pred_mv(sstate: &mut SliceState, frame_refs: &FrameRefs, mb_info: &mut CurrentMBInfo, cur_id: u16, temporal_mv: bool) {
+    fn pred_mv(sstate: &mut SliceState, frame_refs: &FrameRefs, mb_info: &mut CurrentMBInfo, cur_id: u16, temporal_mv: bool, direct_8x8: bool) {
         let mb_type = mb_info.mb_type;
         if !mb_type.is_4x4() {
             let (pw, ph) = mb_type.size();
             let mut xoff = 0;
             let mut yoff = 0;
             if mb_type == MBType::Direct || mb_type == MBType::BSkip {
-                sstate.predict_direct_mb(frame_refs, temporal_mv, cur_id);
+                sstate.predict_direct_mb(frame_refs, temporal_mv, direct_8x8, cur_id);
             }
             for part in 0..mb_type.num_parts() {
                 if !mb_type.is_l1(part) {
@@ -495,7 +495,7 @@ println!("PAFF?");
                         }
                     } else {
                         for sblk in 0..4 {
-                            sstate.predict_direct_sub(frame_refs, temporal_mv, cur_id, (xoff / 4) + (sblk & 1) + (yoff / 4) * 4 + (sblk & 2) * 2);
+                            sstate.predict_direct_sub(frame_refs, temporal_mv, direct_8x8, cur_id, (xoff / 4) + (sblk & 1) + (yoff / 4) * 4 + (sblk & 2) * 2);
                         }
                     }
                     xoff += pw;
@@ -575,7 +575,7 @@ println!("PAFF?");
             self.sstate.reset_mb_mv();
         }
         if !mb_info.mb_type.is_intra() {
-            Self::pred_mv(&mut self.sstate, &self.frame_refs, mb_info, self.cur_id, self.temporal_mv);
+            Self::pred_mv(&mut self.sstate, &self.frame_refs, mb_info, self.cur_id, self.temporal_mv, self.sps[self.cur_sps].direct_8x8_inference);
         }
         if !pps.constrained_intra_pred && mb_info.mb_type != MBType::Intra4x4 && mb_info.mb_type != MBType::Intra8x8 {
             self.sstate.fill_ipred(IntraPredMode::DC);
diff --git a/nihav-itu/src/codecs/h264/types.rs b/nihav-itu/src/codecs/h264/types.rs
index 0a0cc64..3456b99 100644
--- a/nihav-itu/src/codecs/h264/types.rs
+++ b/nihav-itu/src/codecs/h264/types.rs
@@ -445,6 +445,8 @@ pub struct SliceState {
     pub left_c:         [[u8; 9]; 2],
 }
 
+const BLK4_TO_D8: [usize; 16] = [ 0, 0, 3, 3, 0, 0, 3, 3, 12, 12, 15, 15, 12, 12, 15, 15 ];
+
 impl SliceState {
     pub fn new() -> Self {
         Self {
@@ -765,9 +767,15 @@ impl SliceState {
         self.fill_mv (0, 0, 16, 16, 0, mv);
         self.fill_ref(0, 0, 16, 16, 0, ref_idx);
     }
-    pub fn predict_direct_mb(&mut self, frame_refs: &FrameRefs, temporal_mv: bool, cur_id: u16) {
+    pub fn predict_direct_mb(&mut self, frame_refs: &FrameRefs, temporal_mv: bool, direct_8x8: bool, cur_id: u16) {
         let (col_mb, _, _) = frame_refs.get_colocated_info(self.mb_x, self.mb_y);
-        if col_mb.mb_type.is_16x16_ref() || !temporal_mv {
+        if direct_8x8 {
+            for blk4 in 0..16 {
+                let (mv0, ref0, mv1, ref1) = self.get_direct_mv(frame_refs, temporal_mv, cur_id, BLK4_TO_D8[blk4]);
+                self.get_cur_blk4(blk4).mv = [mv0, mv1];
+                self.get_cur_blk8(blk4_to_blk8(blk4)).ref_idx = [ref0, ref1];
+            }
+        } else if col_mb.mb_type.is_16x16_ref() || !temporal_mv {
             let (mv0, ref0, mv1, ref1) = self.get_direct_mv(frame_refs, temporal_mv, cur_id, 0);
             self.apply_to_blk4(|blk4| blk4.mv = [mv0, mv1]);
             self.apply_to_blk8(|blk8| blk8.ref_idx = [ref0, ref1]);
@@ -779,8 +787,9 @@ impl SliceState {
             }
         }
     }
-    pub fn predict_direct_sub(&mut self, frame_refs: &FrameRefs, temporal_mv: bool, cur_id: u16, blk4: usize) {
-        let (mv0, ref0, mv1, ref1) = self.get_direct_mv(frame_refs, temporal_mv, cur_id, blk4);
+    pub fn predict_direct_sub(&mut self, frame_refs: &FrameRefs, temporal_mv: bool, direct8x8: bool, cur_id: u16, blk4: usize) {
+        let src_blk = if !direct8x8 { blk4 } else { BLK4_TO_D8[blk4] };
+        let (mv0, ref0, mv1, ref1) = self.get_direct_mv(frame_refs, temporal_mv, cur_id, src_blk);
         self.get_cur_blk4(blk4).mv = [mv0, mv1];
         self.get_cur_blk8(blk4_to_blk8(blk4)).ref_idx = [ref0, ref1];
     }