ref: f31b3154bd32d990f7d2c8048a7a20f82c0a77af
parent: 862d6f48c5be17ee710ecb9e143cb91e54136160
author: Zoe Liu <zoeliu@google.com>
date: Tue Jun 19 14:11:08 EDT 2018
Add bit allocation for hierarchical layer This CL migrates the bit allocation scheme from libaom and combines the scheme for hierarchical layer with the updated scheme in libvpx that uses a modified scheme to calculate the target bitrate per frame. Change-Id: I63593ed528abd4a6a1a8681abf6c9cf06c7a2ee0
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -2439,6 +2439,149 @@
cpi->multi_arf_last_grp_enabled = cpi->multi_arf_enabled;
}
+static void allocate_gf_multi_arf_bits(VP9_COMP *cpi, int64_t gf_group_bits,
+ int gf_arf_bits) {+ VP9EncoderConfig *const oxcf = &cpi->oxcf;
+ RATE_CONTROL *const rc = &cpi->rc;
+ TWO_PASS *const twopass = &cpi->twopass;
+ GF_GROUP *const gf_group = &twopass->gf_group;
+ FIRSTPASS_STATS frame_stats;
+ int i;
+ int frame_index = 0;
+ int target_frame_size;
+ int key_frame;
+ const int max_bits = frame_max_bits(&cpi->rc, oxcf);
+ int64_t total_group_bits = gf_group_bits;
+ int normal_frames;
+ int normal_frame_bits;
+ int last_frame_reduction = 0;
+ double av_score = 1.0;
+ double tot_norm_frame_score = 1.0;
+ double this_frame_score = 1.0;
+
+ // Define the GF structure and specify
+ define_gf_multi_arf_structure(cpi);
+
+ //========================================
+
+ key_frame = cpi->common.frame_type == KEY_FRAME;
+
+ // For key frames the frame target rate is already set and it
+ // is also the golden frame.
+ // === [frame_index == 0] ===
+ if (!key_frame) {+ gf_group->bit_allocation[frame_index] =
+ rc->source_alt_ref_active ? 0 : gf_arf_bits;
+ }
+
+ // Deduct the boost bits for arf (or gf if it is not a key frame)
+ // from the group total.
+ if (rc->source_alt_ref_pending || !key_frame) total_group_bits -= gf_arf_bits;
+
+ ++frame_index;
+
+ // === [frame_index == 1] ===
+ // Store the bits to spend on the ARF if there is one.
+ if (rc->source_alt_ref_pending) {+ gf_group->bit_allocation[frame_index] = gf_arf_bits;
+
+ ++frame_index;
+
+ // Skip all the extra-ARF's right after ARF at the starting segment of
+ // the current GF group.
+ if (cpi->num_extra_arfs) {+ while (gf_group->update_type[frame_index] == INTNL_ARF_UPDATE)
+ ++frame_index;
+ }
+ }
+
+ normal_frames = (rc->baseline_gf_interval - rc->source_alt_ref_pending);
+ if (normal_frames > 1)
+ normal_frame_bits = (int)(total_group_bits / normal_frames);
+ else
+ normal_frame_bits = (int)total_group_bits;
+
+ if (oxcf->vbr_corpus_complexity) {+ av_score = get_distribution_av_err(cpi, twopass);
+ tot_norm_frame_score = calculate_group_score(cpi, av_score, normal_frames);
+ }
+
+ // Allocate bits to the other frames in the group.
+ for (i = 0; i < normal_frames; ++i) {+ if (EOF == input_stats(twopass, &frame_stats)) break;
+
+ if (oxcf->vbr_corpus_complexity) {+ this_frame_score = calculate_norm_frame_score(cpi, twopass, oxcf,
+ &frame_stats, av_score);
+ normal_frame_bits = (int)((double)total_group_bits *
+ (this_frame_score / tot_norm_frame_score));
+ }
+
+ target_frame_size = normal_frame_bits;
+ if ((i == (normal_frames - 1)) && (i >= 1)) {+ last_frame_reduction = normal_frame_bits / 16;
+ target_frame_size -= last_frame_reduction;
+ }
+
+ if (rc->source_alt_ref_pending && cpi->multi_arf_enabled) {+ target_frame_size -= (target_frame_size >> 4);
+ }
+
+ target_frame_size =
+ clamp(target_frame_size, 0, VPXMIN(max_bits, (int)total_group_bits));
+
+ if (gf_group->update_type[frame_index] == BRF_UPDATE) {+ // Boost up the allocated bits on BWDREF_FRAME
+ gf_group->bit_allocation[frame_index] =
+ target_frame_size + (target_frame_size >> 2);
+ } else if (gf_group->update_type[frame_index] == LAST_BIPRED_UPDATE) {+ // Press down the allocated bits on LAST_BIPRED_UPDATE frames
+ gf_group->bit_allocation[frame_index] =
+ target_frame_size - (target_frame_size >> 1);
+ } else if (gf_group->update_type[frame_index] == BIPRED_UPDATE) {+ // TODO(zoeliu): To investigate whether the allocated bits on
+ // BIPRED_UPDATE frames need to be further adjusted.
+ gf_group->bit_allocation[frame_index] = target_frame_size;
+ } else {+ assert(gf_group->update_type[frame_index] == LF_UPDATE ||
+ gf_group->update_type[frame_index] == INTNL_OVERLAY_UPDATE);
+ gf_group->bit_allocation[frame_index] = target_frame_size;
+ }
+
+ ++frame_index;
+
+ // Skip all the extra-ARF's.
+ if (cpi->num_extra_arfs) {+ while (gf_group->update_type[frame_index] == INTNL_ARF_UPDATE)
+ ++frame_index;
+ }
+ }
+
+ // NOTE: We need to configure the frame at the end of the sequence + 1 that
+ // will be the start frame for the next group. Otherwise prior to the
+ // call to av1_rc_get_second_pass_params() the data will be undefined.
+ if (rc->source_alt_ref_pending) {+ if (cpi->num_extra_arfs) {+ // NOTE: For bit allocation, move the allocated bits associated with
+ // INTNL_OVERLAY_UPDATE to the corresponding INTNL_ARF_UPDATE.
+ // i > 0 for extra-ARF's and i == 0 for ARF:
+ // arf_pos_for_ovrly[i]: Position for INTNL_OVERLAY_UPDATE
+ // arf_pos_in_gf[i]: Position for INTNL_ARF_UPDATE
+ for (i = cpi->num_extra_arfs; i > 0; --i) {+ assert(gf_group->update_type[cpi->arf_pos_for_ovrly[i]] ==
+ INTNL_OVERLAY_UPDATE);
+
+ // Encoder's choice:
+ // Set show_existing_frame == 1 for all extra-ARF's, and hence
+ // allocate zero bit for both all internal OVERLAY frames.
+ gf_group->bit_allocation[cpi->arf_pos_in_gf[i]] =
+ gf_group->bit_allocation[cpi->arf_pos_for_ovrly[i]];
+ gf_group->bit_allocation[cpi->arf_pos_for_ovrly[i]] = 0;
+ }
+ }
+ }
+}
+
static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
int gf_arf_bits) {VP9EncoderConfig *const oxcf = &cpi->oxcf;
@@ -2462,18 +2605,8 @@
double this_frame_score = 1.0;
// Define the GF structure and specify
- cpi->bwd_ref_allowed = 0;
- cpi->extra_arf_allowed = 0;
+ define_gf_group_structure(cpi);
- cpi->num_extra_arfs = 0;
- cpi->num_extra_arfs = cpi->extra_arf_allowed ? cpi->num_extra_arfs : 0;
-
- if (cpi->bwd_ref_allowed) {- define_gf_multi_arf_structure(cpi);
- } else {- define_gf_group_structure(cpi);
- }
-
key_frame = cpi->common.frame_type == KEY_FRAME;
// For key frames the frame target rate is already set and it
@@ -2851,7 +2984,17 @@
twopass->kf_group_error_left -= gf_group_err;
// Allocate bits to each of the frames in the GF group.
- allocate_gf_group_bits(cpi, gf_group_bits, gf_arf_bits);
+ cpi->bwd_ref_allowed = 0;
+ cpi->extra_arf_allowed = 0;
+
+ cpi->num_extra_arfs = 0;
+ cpi->num_extra_arfs = cpi->extra_arf_allowed ? cpi->num_extra_arfs : 0;
+
+ if (cpi->bwd_ref_allowed) {+ allocate_gf_multi_arf_bits(cpi, gf_group_bits, gf_arf_bits);
+ } else {+ allocate_gf_group_bits(cpi, gf_group_bits, gf_arf_bits);
+ }
// Reset the file position.
reset_fpf_position(twopass, start_pos);