ref: e237fd7c5ad8c0caf341ca50a4ea65495edce74f
parent: 59a5c7d5506385b2a034ee2e0a871ea7703f09f1
author: Paul Wilkins <paulwilkins@google.com>
date: Mon May 14 11:13:26 EDT 2012
Two pass refactoring continued. Remove testing of whether we estimate that it will be possible to code an arf at a lower Q than the ambient Q. This adds quite a bit of extra code and complexity for marginal gain. Factored out some code relating to ARNR selection to a separate function as this is likely to be changed / simplified soon. Change-Id: Ia1cf060405637ef5bbf7018355437be21d12375f
--- a/vp8/encoder/firstpass.c
+++ b/vp8/encoder/firstpass.c
@@ -807,6 +807,9 @@
{vp8_yv12_copy_frame_ptr(lst_yv12, gld_yv12);
}
+ {+ vp8_yv12_copy_frame_ptr(lst_yv12, gld_yv12);
+ }
// swap frame pointers so last frame refers to the frame we just compressed
vp8_swap_yv12_buffer(lst_yv12, new_yv12);
@@ -1148,50 +1151,6 @@
return Q;
}
-static int estimate_q(VP8_COMP *cpi, double section_err, int section_target_bandwitdh)
-{- int Q;
- int num_mbs = cpi->common.MBs;
- int target_norm_bits_per_mb;
-
- double err_per_mb = section_err / num_mbs;
- double err_correction_factor;
- double corr_high;
- double speed_correction = 1.0;
-
- target_norm_bits_per_mb = (section_target_bandwitdh < (1 << 20)) ? (512 * section_target_bandwitdh) / num_mbs : 512 * (section_target_bandwitdh / num_mbs);
-
- // Corrections for higher compression speed settings (reduced compression expected)
- if (cpi->compressor_speed == 1)
- {- if (cpi->oxcf.cpu_used <= 5)
- speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
- else
- speed_correction = 1.25;
- }
-
- // Try and pick a Q that can encode the content at the given rate.
- for (Q = 0; Q < MAXQ; Q++)
- {- int bits_per_mb_at_this_q;
-
- // Error per MB based correction factor
- err_correction_factor =
- calc_correction_factor(err_per_mb, ERR_DIVISOR, 0.36, 0.90, Q);
-
- bits_per_mb_at_this_q =
- (int)( .5 + ( err_correction_factor *
- speed_correction *
- cpi->twopass.est_max_qcorrection_factor *
- (double)vp8_bits_per_mb(INTER_FRAME, Q) / 1.0 ) );
-
- if (bits_per_mb_at_this_q <= target_norm_bits_per_mb)
- break;
- }
-
- return Q;
-}
-
// Estimate a worst case Q for a KF group
static int estimate_kf_group_q(VP8_COMP *cpi, double section_err, int section_target_bandwitdh, double group_iiratio)
{@@ -1677,6 +1636,59 @@
return (*f_boost + *b_boost);
}
+static void configure_arnr_filter( VP8_COMP *cpi, FIRSTPASS_STATS *this_frame )
+{+ int half_gf_int;
+ int frames_after_arf;
+ int frames_bwd = cpi->oxcf.arnr_max_frames - 1;
+ int frames_fwd = cpi->oxcf.arnr_max_frames - 1;
+
+ // Define the arnr filter width for this group of frames:
+ // We only filter frames that lie within a distance of half
+ // the GF interval from the ARF frame. We also have to trap
+ // cases where the filter extends beyond the end of clip.
+ // Note: this_frame->frame has been updated in the loop
+ // so it now points at the ARF frame.
+ half_gf_int = cpi->baseline_gf_interval >> 1;
+ frames_after_arf = cpi->twopass.total_stats->count -
+ this_frame->frame - 1;
+
+ switch (cpi->oxcf.arnr_type)
+ {+ case 1: // Backward filter
+ frames_fwd = 0;
+ if (frames_bwd > half_gf_int)
+ frames_bwd = half_gf_int;
+ break;
+
+ case 2: // Forward filter
+ if (frames_fwd > half_gf_int)
+ frames_fwd = half_gf_int;
+ if (frames_fwd > frames_after_arf)
+ frames_fwd = frames_after_arf;
+ frames_bwd = 0;
+ break;
+
+ case 3: // Centered filter
+ default:
+ frames_fwd >>= 1;
+ if (frames_fwd > frames_after_arf)
+ frames_fwd = frames_after_arf;
+ if (frames_fwd > half_gf_int)
+ frames_fwd = half_gf_int;
+
+ frames_bwd = frames_fwd;
+
+ // For even length filter there is one more frame backward
+ // than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
+ if (frames_bwd < half_gf_int)
+ frames_bwd += (cpi->oxcf.arnr_max_frames+1) & 0x1;
+ break;
+ }
+
+ cpi->active_arnr_frames = frames_bwd + 1 + frames_fwd;
+}
+
// Analyse and define a gf/arf group .
static void define_gf_group(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
{@@ -1834,6 +1846,9 @@
// Alterrnative boost calculation for alt ref
alt_boost = calc_arf_boost( cpi, 0, (i-1), (i-1), &f_boost, &b_boost );
+ // Set the interval till the next gf or arf.
+ cpi->baseline_gf_interval = i;
+
// Should we use the alternate refernce frame
if (allow_alt_ref &&
(i < cpi->oxcf.lag_in_frames ) &&
@@ -1846,139 +1861,16 @@
(mv_in_out_accumulator > -2.0)) &&
(b_boost > 100) &&
(f_boost > 100) )
- {- int Boost;
- int allocation_chunks;
- int Q = (cpi->oxcf.fixed_q < 0)
- ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q;
- int tmp_q;
- int arf_frame_bits = 0;
- int group_bits;
+ {cpi->gfu_boost = alt_boost;
+ cpi->source_alt_ref_pending = TRUE;
- // Estimate the bits to be allocated to the group as a whole
- if ((cpi->twopass.kf_group_bits > 0) &&
- (cpi->twopass.kf_group_error_left > 0))
- {- group_bits = (int)((double)cpi->twopass.kf_group_bits *
- (gf_group_err / (double)cpi->twopass.kf_group_error_left));
- }
- else
- group_bits = 0;
-
- // Boost for arf frame
- Boost = (alt_boost * vp8_gfboost_qadjust(Q)) / 100;
- Boost += (i * 50);
-
- // Set max and minimum boost and hence minimum allocation
- if (Boost > ((cpi->baseline_gf_interval + 1) * 200))
- Boost = ((cpi->baseline_gf_interval + 1) * 200);
- else if (Boost < 125)
- Boost = 125;
-
- allocation_chunks = (i * 100) + Boost;
-
- // Prevent overflow
- if ( Boost > 1028 )
- {- int divisor = Boost >> 10;
- Boost /= divisor;
- allocation_chunks /= divisor;
- }
-
- // Calculate the number of bits to be spent on the arf based on the
- // boost number
- arf_frame_bits = (int)((double)Boost * (group_bits /
- (double)allocation_chunks));
-
- // Estimate if there are enough bits available to make worthwhile use
- // of an arf.
- tmp_q = estimate_q(cpi, mod_frame_err, (int)arf_frame_bits);
-
- // Only use an arf if it is likely we will be able to code
- // it at a lower Q than the surrounding frames.
- if (tmp_q < cpi->worst_quality)
- {- int half_gf_int;
- int frames_after_arf;
- int frames_bwd = cpi->oxcf.arnr_max_frames - 1;
- int frames_fwd = cpi->oxcf.arnr_max_frames - 1;
-
- cpi->source_alt_ref_pending = TRUE;
-
- // For alt ref frames the error score for the end frame of the
- // group (the alt ref frame) should not contribute to the group
- // total and hence the number of bit allocated to the group.
- // Rather it forms part of the next group (it is the GF at the
- // start of the next group)
- // gf_group_err -= mod_frame_err;
-
- // For alt ref frames alt ref frame is technically part of the
- // GF frame for the next group but we always base the error
- // calculation and bit allocation on the current group of frames.
-
- // Set the interval till the next gf or arf.
- // For ARFs this is the number of frames to be coded before the
- // future frame that is coded as an ARF.
- // The future frame itself is part of the next group
- cpi->baseline_gf_interval = i;
-
- // Define the arnr filter width for this group of frames:
- // We only filter frames that lie within a distance of half
- // the GF interval from the ARF frame. We also have to trap
- // cases where the filter extends beyond the end of clip.
- // Note: this_frame->frame has been updated in the loop
- // so it now points at the ARF frame.
- half_gf_int = cpi->baseline_gf_interval >> 1;
- frames_after_arf = cpi->twopass.total_stats->count -
- this_frame->frame - 1;
-
- switch (cpi->oxcf.arnr_type)
- {- case 1: // Backward filter
- frames_fwd = 0;
- if (frames_bwd > half_gf_int)
- frames_bwd = half_gf_int;
- break;
-
- case 2: // Forward filter
- if (frames_fwd > half_gf_int)
- frames_fwd = half_gf_int;
- if (frames_fwd > frames_after_arf)
- frames_fwd = frames_after_arf;
- frames_bwd = 0;
- break;
-
- case 3: // Centered filter
- default:
- frames_fwd >>= 1;
- if (frames_fwd > frames_after_arf)
- frames_fwd = frames_after_arf;
- if (frames_fwd > half_gf_int)
- frames_fwd = half_gf_int;
-
- frames_bwd = frames_fwd;
-
- // For even length filter there is one more frame backward
- // than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
- if (frames_bwd < half_gf_int)
- frames_bwd += (cpi->oxcf.arnr_max_frames+1) & 0x1;
- break;
- }
-
- cpi->active_arnr_frames = frames_bwd + 1 + frames_fwd;
- }
- else
- {- cpi->source_alt_ref_pending = FALSE;
- cpi->baseline_gf_interval = i;
- }
+ configure_arnr_filter( cpi, this_frame );
}
else
{cpi->source_alt_ref_pending = FALSE;
- cpi->baseline_gf_interval = i;
}
// Now decide how many bits should be allocated to the GF group as a
--
⑨