1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include <assert.h>
12 #include <limits.h>
13
14 #include "./vpx_scale_rtcd.h"
15 #include "vpx_dsp/psnr.h"
16 #include "vpx_mem/vpx_mem.h"
17 #include "vpx_ports/mem.h"
18
19 #include "vp9/common/vp9_loopfilter.h"
20 #include "vp9/common/vp9_onyxc_int.h"
21 #include "vp9/common/vp9_quant_common.h"
22
23 #include "vp9/encoder/vp9_encoder.h"
24 #include "vp9/encoder/vp9_picklpf.h"
25 #include "vp9/encoder/vp9_quantize.h"
26
get_section_intra_rating(const VP9_COMP * cpi)27 static unsigned int get_section_intra_rating(const VP9_COMP *cpi) {
28 unsigned int section_intra_rating;
29
30 section_intra_rating = (cpi->common.frame_type == KEY_FRAME)
31 ? cpi->twopass.key_frame_section_intra_rating
32 : cpi->twopass.section_intra_rating;
33
34 return section_intra_rating;
35 }
36
get_max_filter_level(const VP9_COMP * cpi)37 static int get_max_filter_level(const VP9_COMP *cpi) {
38 if (cpi->oxcf.pass == 2) {
39 unsigned int section_intra_rating = get_section_intra_rating(cpi);
40 return section_intra_rating > 8 ? MAX_LOOP_FILTER * 3 / 4 : MAX_LOOP_FILTER;
41 } else {
42 return MAX_LOOP_FILTER;
43 }
44 }
45
try_filter_frame(const YV12_BUFFER_CONFIG * sd,VP9_COMP * const cpi,int filt_level,int partial_frame)46 static int64_t try_filter_frame(const YV12_BUFFER_CONFIG *sd,
47 VP9_COMP *const cpi, int filt_level,
48 int partial_frame) {
49 VP9_COMMON *const cm = &cpi->common;
50 int64_t filt_err;
51
52 vp9_build_mask_frame(cm, filt_level, partial_frame);
53
54 if (cpi->num_workers > 1)
55 vp9_loop_filter_frame_mt(cm->frame_to_show, cm, cpi->td.mb.e_mbd.plane,
56 filt_level, 1, partial_frame, cpi->workers,
57 cpi->num_workers, &cpi->lf_row_sync);
58 else
59 vp9_loop_filter_frame(cm->frame_to_show, cm, &cpi->td.mb.e_mbd, filt_level,
60 1, partial_frame);
61
62 #if CONFIG_VP9_HIGHBITDEPTH
63 if (cm->use_highbitdepth) {
64 filt_err = vpx_highbd_get_y_sse(sd, cm->frame_to_show);
65 } else {
66 filt_err = vpx_get_y_sse(sd, cm->frame_to_show);
67 }
68 #else
69 filt_err = vpx_get_y_sse(sd, cm->frame_to_show);
70 #endif // CONFIG_VP9_HIGHBITDEPTH
71
72 // Re-instate the unfiltered frame
73 vpx_yv12_copy_y(&cpi->last_frame_uf, cm->frame_to_show);
74
75 return filt_err;
76 }
77
search_filter_level(const YV12_BUFFER_CONFIG * sd,VP9_COMP * cpi,int partial_frame)78 static int search_filter_level(const YV12_BUFFER_CONFIG *sd, VP9_COMP *cpi,
79 int partial_frame) {
80 const VP9_COMMON *const cm = &cpi->common;
81 const struct loopfilter *const lf = &cm->lf;
82 const int min_filter_level = 0;
83 const int max_filter_level = get_max_filter_level(cpi);
84 int filt_direction = 0;
85 int64_t best_err;
86 int filt_best;
87
88 // Start the search at the previous frame filter level unless it is now out of
89 // range.
90 int filt_mid = clamp(lf->last_filt_level, min_filter_level, max_filter_level);
91 int filter_step = filt_mid < 16 ? 4 : filt_mid / 4;
92 // Sum squared error at each filter level
93 int64_t ss_err[MAX_LOOP_FILTER + 1];
94 unsigned int section_intra_rating = get_section_intra_rating(cpi);
95
96 // Set each entry to -1
97 memset(ss_err, 0xFF, sizeof(ss_err));
98
99 // Make a copy of the unfiltered / processed recon buffer
100 vpx_yv12_copy_y(cm->frame_to_show, &cpi->last_frame_uf);
101
102 best_err = try_filter_frame(sd, cpi, filt_mid, partial_frame);
103 filt_best = filt_mid;
104 ss_err[filt_mid] = best_err;
105
106 while (filter_step > 0) {
107 const int filt_high = VPXMIN(filt_mid + filter_step, max_filter_level);
108 const int filt_low = VPXMAX(filt_mid - filter_step, min_filter_level);
109
110 // Bias against raising loop filter in favor of lowering it.
111 int64_t bias = (best_err >> (15 - (filt_mid / 8))) * filter_step;
112
113 if ((cpi->oxcf.pass == 2) && (section_intra_rating < 20))
114 bias = (bias * section_intra_rating) / 20;
115
116 // yx, bias less for large block size
117 if (cm->tx_mode != ONLY_4X4) bias >>= 1;
118
119 if (filt_direction <= 0 && filt_low != filt_mid) {
120 // Get Low filter error score
121 if (ss_err[filt_low] < 0) {
122 ss_err[filt_low] = try_filter_frame(sd, cpi, filt_low, partial_frame);
123 }
124 // If value is close to the best so far then bias towards a lower loop
125 // filter value.
126 if ((ss_err[filt_low] - bias) < best_err) {
127 // Was it actually better than the previous best?
128 if (ss_err[filt_low] < best_err) best_err = ss_err[filt_low];
129
130 filt_best = filt_low;
131 }
132 }
133
134 // Now look at filt_high
135 if (filt_direction >= 0 && filt_high != filt_mid) {
136 if (ss_err[filt_high] < 0) {
137 ss_err[filt_high] = try_filter_frame(sd, cpi, filt_high, partial_frame);
138 }
139 // Was it better than the previous best?
140 if (ss_err[filt_high] < (best_err - bias)) {
141 best_err = ss_err[filt_high];
142 filt_best = filt_high;
143 }
144 }
145
146 // Half the step distance if the best filter value was the same as last time
147 if (filt_best == filt_mid) {
148 filter_step /= 2;
149 filt_direction = 0;
150 } else {
151 filt_direction = (filt_best < filt_mid) ? -1 : 1;
152 filt_mid = filt_best;
153 }
154 }
155
156 return filt_best;
157 }
158
vp9_pick_filter_level(const YV12_BUFFER_CONFIG * sd,VP9_COMP * cpi,LPF_PICK_METHOD method)159 void vp9_pick_filter_level(const YV12_BUFFER_CONFIG *sd, VP9_COMP *cpi,
160 LPF_PICK_METHOD method) {
161 VP9_COMMON *const cm = &cpi->common;
162 struct loopfilter *const lf = &cm->lf;
163
164 lf->sharpness_level = 0;
165
166 if (method == LPF_PICK_MINIMAL_LPF && lf->filter_level) {
167 lf->filter_level = 0;
168 } else if (method >= LPF_PICK_FROM_Q) {
169 const int min_filter_level = 0;
170 const int max_filter_level = get_max_filter_level(cpi);
171 const int q = vp9_ac_quant(cm->base_qindex, 0, cm->bit_depth);
172 // These values were determined by linear fitting the result of the
173 // searched level, filt_guess = q * 0.316206 + 3.87252
174 #if CONFIG_VP9_HIGHBITDEPTH
175 int filt_guess;
176 switch (cm->bit_depth) {
177 case VPX_BITS_8:
178 filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 1015158, 18);
179 break;
180 case VPX_BITS_10:
181 filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 4060632, 20);
182 break;
183 default:
184 assert(cm->bit_depth == VPX_BITS_12);
185 filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 16242526, 22);
186 break;
187 }
188 #else
189 int filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 1015158, 18);
190 #endif // CONFIG_VP9_HIGHBITDEPTH
191 if (cpi->oxcf.pass == 0 && cpi->oxcf.rc_mode == VPX_CBR &&
192 cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cm->seg.enabled &&
193 (cm->base_qindex < 200 || cm->width * cm->height > 320 * 240) &&
194 cpi->oxcf.content != VP9E_CONTENT_SCREEN && cm->frame_type != KEY_FRAME)
195 filt_guess = 5 * filt_guess >> 3;
196
197 if (cm->frame_type == KEY_FRAME) filt_guess -= 4;
198 lf->filter_level = clamp(filt_guess, min_filter_level, max_filter_level);
199 } else {
200 lf->filter_level =
201 search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE);
202 }
203 }
204