CWG-D047 Add by-pass check in deblocking strength decision
It's an encoder side bug fix in function av1_pick_filter_level(), where
it missed the by-pass check (no deblocking) during rdcost comparisons.
The bug fix could potentially save bits signalling when no deblocking
case wins. The bdrate gain on a4 and a5 testsets are as below:
| Testset | avg_psnr | ovr_psnr | ssim | vmaf |
| ------ | ------ | ------ | ------ | ------ |
| a4 | -0.146 | -0.192 | -0.098 | -0.011 |
| a5 | -0.078 | -0.060 | -0.058 | 0.006 |
diff --git a/av1/encoder/picklpf.c b/av1/encoder/picklpf.c
index 113bf17..452ab8d 100644
--- a/av1/encoder/picklpf.c
+++ b/av1/encoder/picklpf.c
@@ -321,6 +321,17 @@
cpi->td.mb.rdmult = cpi->rd.RDMULT;
+ double no_deblocking_cost[MAX_MB_PLANE] = { DBL_MAX, DBL_MAX, DBL_MAX };
+
+ for (int i = 0; i < num_planes; i++) {
+ const int chroma_lambda_mult = i ? CHROMA_LAMBDA_MULT : 1;
+ const int64_t no_deblocking_sse =
+ aom_get_sse_plane(cpi->source, &cm->cur_frame->buf, i);
+ no_deblocking_cost[i] = RDCOST_DBL_WITH_NATIVE_BD_DIST(
+ cpi->td.mb.rdmult * chroma_lambda_mult, 0, no_deblocking_sse,
+ cm->seq_params.bit_depth);
+ }
+
if (method == LPF_PICK_MINIMAL_LPF) {
lf->filter_level[0] = 0;
lf->filter_level[1] = 0;
@@ -416,7 +427,12 @@
last_frame_offsets[2] = lf->delta_q_luma[1] = lf->delta_side_luma[1];
#endif // DF_TWO_PARAM
- if (best_single_cost < best_dual_cost) {
+ if (no_deblocking_cost[0] < AOMMIN(best_single_cost, best_dual_cost)) {
+ lf->filter_level[0] = 0;
+ lf->filter_level[1] = 0;
+ lf->delta_q_luma[0] = lf->delta_side_luma[0] = lf->delta_q_luma[1] =
+ lf->delta_side_luma[1] = 0;
+ } else if (best_single_cost < best_dual_cost) {
lf->delta_q_luma[0] = last_frame_offsets[0] = best_single_offsets[0];
lf->delta_side_luma[0] = last_frame_offsets[1] = best_single_offsets[1];
lf->delta_q_luma[1] = last_frame_offsets[2] = best_single_offsets[2];
@@ -424,10 +440,12 @@
}
if (num_planes > 1) {
+ double best_cost_u = DBL_MAX;
+ double best_cost_v = DBL_MAX;
// Cb
last_frame_offsets[5] = lf->delta_side_u =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
- last_frame_offsets, NULL, 1, 1, dir);
+ last_frame_offsets, &best_cost_u, 1, 1, dir);
#if DF_TWO_PARAM
last_frame_offsets[4] = lf->delta_q_u =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
@@ -438,7 +456,7 @@
last_frame_offsets[5] = lf->delta_side_u =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
- last_frame_offsets, NULL, 1, 1, dir);
+ last_frame_offsets, &best_cost_u, 1, 1, dir);
#if DF_TWO_PARAM
last_frame_offsets[4] = lf->delta_q_u =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
@@ -446,10 +464,16 @@
#else
last_frame_offsets[4] = lf->delta_q_u = lf->delta_side_u;
#endif // DF_TWO_PARAM
+
+ if (no_deblocking_cost[1] < best_cost_u) {
+ lf->filter_level_u = 0;
+ lf->delta_q_u = lf->delta_side_u = 0;
+ }
+
// Cr
last_frame_offsets[7] = lf->delta_side_v =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
- last_frame_offsets, NULL, 2, 1, dir);
+ last_frame_offsets, &best_cost_v, 2, 1, dir);
#if DF_TWO_PARAM
last_frame_offsets[6] = lf->delta_q_v =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
@@ -459,7 +483,7 @@
#endif // DF_TWO_PARAM
last_frame_offsets[7] = lf->delta_side_v =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
- last_frame_offsets, NULL, 2, 1, dir);
+ last_frame_offsets, &best_cost_v, 2, 1, dir);
#if DF_TWO_PARAM
last_frame_offsets[6] = lf->delta_q_v =
search_filter_offsets(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
@@ -468,6 +492,11 @@
last_frame_offsets[6] = lf->delta_q_v = lf->delta_side_v;
#endif // DF_TWO_PARAM
+ if (no_deblocking_cost[2] < best_cost_v) {
+ lf->filter_level_v = 0;
+ lf->delta_q_v = lf->delta_side_v = 0;
+ }
+
// to switch off filters if offsets are zero
if (!df_quant_from_qindex(cm->quant_params.base_qindex +
cm->lf.delta_q_luma[0] * DF_DELTA_SCALE,
