Signal delta loop filter level between superblocks For the first superblock, signal a filter level (6 bit). For other superblocks, signal the delta (3 bit) and sign (1 bit). To guarantee the delta can be represented by 3 bits, the search range of current superblock filter level is capped as curr_lvl = prev_lvl +- ((1 << 3) - 1) Change-Id: Ibbe2941aa96ec1220ed2adb7edf3d29cb032f0ec
diff --git a/av1/common/enums.h b/av1/common/enums.h index 6857818..af8b826 100644 --- a/av1/common/enums.h +++ b/av1/common/enums.h
@@ -82,6 +82,11 @@ #define MI_SIZE_64X64 (64 >> MI_SIZE_LOG2) +#if CONFIG_LPF_SB +#define LPF_DELTA_BITS 3 +#define MAX_LPF_OFFSET ((1 << LPF_DELTA_BITS) - 1) +#endif // CONFIG_LPF_SB + // Bitstream profiles indicated by 2-3 bits in the uncompressed header. // 00: Profile 0. 8-bit 4:2:0 only. // 10: Profile 1. 8-bit 4:4:4, 4:2:2, and 4:4:0.
diff --git a/av1/decoder/decodeframe.c b/av1/decoder/decodeframe.c index 4f3254c..d81a21a 100644 --- a/av1/decoder/decodeframe.c +++ b/av1/decoder/decodeframe.c
@@ -2538,7 +2538,30 @@ #if CONFIG_LPF_SB if (bsize == cm->sb_size) { - int filt_lvl = aom_read_literal(r, 6, ACCT_STR); + int filt_lvl; + if (mi_row == 0 && mi_col == 0) { + filt_lvl = aom_read_literal(r, 6, ACCT_STR); + } else { + int prev_mi_row, prev_mi_col; + if (mi_col - MAX_MIB_SIZE < 0) { + prev_mi_row = mi_row - MAX_MIB_SIZE; + prev_mi_col = mi_col; + } else { + prev_mi_row = mi_row; + prev_mi_col = mi_col - MAX_MIB_SIZE; + } + const uint8_t prev_lvl = + cm->mi_grid_visible[prev_mi_row * cm->mi_stride + prev_mi_col] + ->mbmi.filt_lvl; + + const unsigned int delta = aom_read_literal(r, LPF_DELTA_BITS, ACCT_STR); + if (delta) { + const int sign = aom_read_literal(r, 1, ACCT_STR); + filt_lvl = sign ? prev_lvl + delta : prev_lvl - delta; + } else { + filt_lvl = prev_lvl; + } + } int row, col; // set filter level for each mbmi for (row = mi_row; row < mi_row + MAX_MIB_SIZE && row < cm->mi_rows;
diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c index 4019364..d5b9380 100644 --- a/av1/encoder/bitstream.c +++ b/av1/encoder/bitstream.c
@@ -3131,9 +3131,33 @@ #if CONFIG_LPF_SB // send filter level for each superblock (64x64) if (bsize == cm->sb_size) { - aom_write_literal( - w, cm->mi_grid_visible[mi_row * cm->mi_stride + mi_col]->mbmi.filt_lvl, - 6); + if (mi_row == 0 && mi_col == 0) { + aom_write_literal( + w, + cm->mi_grid_visible[mi_row * cm->mi_stride + mi_col]->mbmi.filt_lvl, + 6); + } else { + int prev_mi_row, prev_mi_col; + if (mi_col - MAX_MIB_SIZE < 0) { + prev_mi_row = mi_row - MAX_MIB_SIZE; + prev_mi_col = mi_col; + } else { + prev_mi_row = mi_row; + prev_mi_col = mi_col - MAX_MIB_SIZE; + } + MB_MODE_INFO *curr_mbmi = + &cm->mi_grid_visible[mi_row * cm->mi_stride + mi_col]->mbmi; + MB_MODE_INFO *prev_mbmi = + &cm->mi_grid_visible[prev_mi_row * cm->mi_stride + prev_mi_col]->mbmi; + + const uint8_t curr_lvl = curr_mbmi->filt_lvl; + const uint8_t prev_lvl = prev_mbmi->filt_lvl; + const int sign = curr_lvl > prev_lvl; + const unsigned int delta = abs(curr_lvl - prev_lvl); + + aom_write_literal(w, delta, LPF_DELTA_BITS); + if (delta) aom_write_literal(w, sign, 1); + } } #endif
diff --git a/av1/encoder/picklpf.c b/av1/encoder/picklpf.c index 820633c..185bc55 100644 --- a/av1/encoder/picklpf.c +++ b/av1/encoder/picklpf.c
@@ -135,91 +135,26 @@ int partial_frame, double *best_cost_ret, int mi_row, int mi_col, int last_lvl) { const AV1_COMMON *const cm = &cpi->common; - const struct loopfilter *const lf = &cm->lf; - const int min_filter_level = 0; - const int max_filter_level = av1_get_max_filter_level(cpi); - int filt_direction = 0; - int64_t best_err; - int filt_best; + const int min_filter_level = AOMMAX(0, last_lvl - MAX_LPF_OFFSET); + const int max_filter_level = + AOMMIN(av1_get_max_filter_level(cpi), last_lvl + MAX_LPF_OFFSET); + int64_t best_err = INT64_MAX; + int filt_best = last_lvl; MACROBLOCK *x = &cpi->td.mb; - // Start the search at the previous frame filter level unless it is now out of - // range. - int filt_mid = clamp(last_lvl, min_filter_level, max_filter_level); - (void)lf; - int filter_step = filt_mid < 16 ? 4 : filt_mid / 4; - // Sum squared error at each filter level - int64_t ss_err[MAX_LOOP_FILTER + 1]; - - // Set each entry to -1 - memset(ss_err, 0xFF, sizeof(ss_err)); - // Make a copy of the unfiltered / processed recon buffer aom_yv12_copy_y(cm->frame_to_show, &cpi->last_frame_uf); - best_err = try_filter_frame(sd, cpi, filt_mid, partial_frame, mi_row, mi_col); - filt_best = filt_mid; - ss_err[filt_mid] = best_err; - - while (filter_step > 0) { - const int filt_high = AOMMIN(filt_mid + filter_step, max_filter_level); - const int filt_low = AOMMAX(filt_mid - filter_step, min_filter_level); - - // Bias against raising loop filter in favor of lowering it. - int64_t bias = (best_err >> (15 - (filt_mid / 8))) * filter_step; - - if ((cpi->oxcf.pass == 2) && (cpi->twopass.section_intra_rating < 20)) - bias = (bias * cpi->twopass.section_intra_rating) / 20; - - // yx, bias less for large block size - if (cm->tx_mode != ONLY_4X4) bias >>= 1; - - bias = 0; - - if (filt_direction <= 0 && filt_low != filt_mid) { - // Get Low filter error score - if (ss_err[filt_low] < 0) { - ss_err[filt_low] = - try_filter_frame(sd, cpi, filt_low, partial_frame, mi_row, mi_col); - } - // If value is close to the best so far then bias towards a lower loop - // filter value. - if (ss_err[filt_low] < (best_err + bias)) { - // Was it actually better than the previous best? - if (ss_err[filt_low] < best_err) { - best_err = ss_err[filt_low]; - } - filt_best = filt_low; - } - } - - // Now look at filt_high - if (filt_direction >= 0 && filt_high != filt_mid) { - if (ss_err[filt_high] < 0) { - ss_err[filt_high] = - try_filter_frame(sd, cpi, filt_high, partial_frame, mi_row, mi_col); - } - // If value is significantly better than previous best, bias added against - // raising filter value - if (ss_err[filt_high] < (best_err - bias)) { - best_err = ss_err[filt_high]; - filt_best = filt_high; - } - } - - // Half the step distance if the best filter value was the same as last time - if (filt_best == filt_mid) { - filter_step /= 2; - filt_direction = 0; - } else { - filt_direction = (filt_best < filt_mid) ? -1 : 1; - filt_mid = filt_best; + int i; + for (i = min_filter_level; i <= max_filter_level; ++i) { + int64_t filt_err = + try_filter_frame(sd, cpi, i, partial_frame, mi_row, mi_col); + if (filt_err < best_err) { + best_err = filt_err; + filt_best = i; } } - // Update best error - best_err = ss_err[filt_best]; - if (best_cost_ret) *best_cost_ret = RDCOST_DBL(x->rdmult, 0, best_err); return filt_best; } @@ -465,7 +400,14 @@ cm->mi_grid_visible[row * cm->mi_stride + col]->mbmi.filt_lvl = lvl; } } - last_lvl = lvl; + + // For the superblock at row start, its previous filter level should be + // the one above it, not the one at the end of last row + if (mi_col + MAX_MIB_SIZE >= cm->mi_cols) { + last_lvl = cm->mi_grid_visible[mi_row * cm->mi_stride]->mbmi.filt_lvl; + } else { + last_lvl = lvl; + } } } #else