1/*
2 *  Copyright (c) 2014 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 <math.h>
12
13#include "vp9/encoder/vp9_onyx_int.h"
14#include "vp9/encoder/vp9_svc_layercontext.h"
15
16void vp9_init_layer_context(VP9_COMP *const cpi) {
17  const VP9_CONFIG *const oxcf = &cpi->oxcf;
18  int layer;
19  int layer_end;
20
21  cpi->svc.spatial_layer_id = 0;
22  cpi->svc.temporal_layer_id = 0;
23
24  if (cpi->svc.number_temporal_layers > 1) {
25    layer_end = cpi->svc.number_temporal_layers;
26  } else {
27    layer_end = cpi->svc.number_spatial_layers;
28  }
29
30  for (layer = 0; layer < layer_end; ++layer) {
31    LAYER_CONTEXT *const lc = &cpi->svc.layer_context[layer];
32    RATE_CONTROL *const lrc = &lc->rc;
33    lc->current_video_frame_in_layer = 0;
34    lrc->avg_frame_qindex[INTER_FRAME] = q_trans[oxcf->worst_allowed_q];
35    lrc->ni_av_qi = q_trans[oxcf->worst_allowed_q];
36    lrc->total_actual_bits = 0;
37    lrc->total_target_vs_actual = 0;
38    lrc->ni_tot_qi = 0;
39    lrc->tot_q = 0.0;
40    lrc->avg_q = 0.0;
41    lrc->ni_frames = 0;
42    lrc->decimation_count = 0;
43    lrc->decimation_factor = 0;
44    lrc->rate_correction_factor = 1.0;
45    lrc->key_frame_rate_correction_factor = 1.0;
46
47    if (cpi->svc.number_temporal_layers > 1) {
48      lc->target_bandwidth = oxcf->ts_target_bitrate[layer] * 1000;
49      lrc->last_q[INTER_FRAME] = q_trans[oxcf->worst_allowed_q];
50    } else {
51      lc->target_bandwidth = oxcf->ss_target_bitrate[layer] * 1000;
52      lrc->last_q[0] = q_trans[oxcf->best_allowed_q];
53      lrc->last_q[1] = q_trans[oxcf->best_allowed_q];
54      lrc->last_q[2] = q_trans[oxcf->best_allowed_q];
55    }
56
57    lrc->buffer_level = vp9_rescale((int)(oxcf->starting_buffer_level),
58                                    lc->target_bandwidth, 1000);
59    lrc->bits_off_target = lrc->buffer_level;
60  }
61}
62
63// Update the layer context from a change_config() call.
64void vp9_update_layer_context_change_config(VP9_COMP *const cpi,
65                                            const int target_bandwidth) {
66  const VP9_CONFIG *const oxcf = &cpi->oxcf;
67  const RATE_CONTROL *const rc = &cpi->rc;
68  int layer;
69  int layer_end;
70  float bitrate_alloc = 1.0;
71
72  if (cpi->svc.number_temporal_layers > 1) {
73    layer_end = cpi->svc.number_temporal_layers;
74  } else {
75    layer_end = cpi->svc.number_spatial_layers;
76  }
77
78  for (layer = 0; layer < layer_end; ++layer) {
79    LAYER_CONTEXT *const lc = &cpi->svc.layer_context[layer];
80    RATE_CONTROL *const lrc = &lc->rc;
81
82    if (cpi->svc.number_temporal_layers > 1) {
83      lc->target_bandwidth = oxcf->ts_target_bitrate[layer] * 1000;
84    } else {
85      lc->target_bandwidth = oxcf->ss_target_bitrate[layer] * 1000;
86    }
87    bitrate_alloc = (float)lc->target_bandwidth / target_bandwidth;
88    // Update buffer-related quantities.
89    lc->starting_buffer_level =
90        (int64_t)(oxcf->starting_buffer_level * bitrate_alloc);
91    lc->optimal_buffer_level =
92        (int64_t)(oxcf->optimal_buffer_level * bitrate_alloc);
93    lc->maximum_buffer_size =
94        (int64_t)(oxcf->maximum_buffer_size * bitrate_alloc);
95    lrc->bits_off_target = MIN(lrc->bits_off_target, lc->maximum_buffer_size);
96    lrc->buffer_level = MIN(lrc->buffer_level, lc->maximum_buffer_size);
97    // Update framerate-related quantities.
98    if (cpi->svc.number_temporal_layers > 1) {
99      lc->framerate = oxcf->framerate / oxcf->ts_rate_decimator[layer];
100    } else {
101      lc->framerate = oxcf->framerate;
102    }
103    lrc->av_per_frame_bandwidth = (int)(lc->target_bandwidth / lc->framerate);
104    lrc->max_frame_bandwidth = rc->max_frame_bandwidth;
105    // Update qp-related quantities.
106    lrc->worst_quality = rc->worst_quality;
107    lrc->best_quality = rc->best_quality;
108  }
109}
110
111static LAYER_CONTEXT *get_layer_context(SVC *svc) {
112  return svc->number_temporal_layers > 1 ?
113         &svc->layer_context[svc->temporal_layer_id] :
114         &svc->layer_context[svc->spatial_layer_id];
115}
116
117void vp9_update_temporal_layer_framerate(VP9_COMP *const cpi) {
118  const int layer = cpi->svc.temporal_layer_id;
119  const VP9_CONFIG *const oxcf = &cpi->oxcf;
120  LAYER_CONTEXT *const lc = get_layer_context(&cpi->svc);
121  RATE_CONTROL *const lrc = &lc->rc;
122
123  lc->framerate = oxcf->framerate / oxcf->ts_rate_decimator[layer];
124  lrc->av_per_frame_bandwidth = (int)(lc->target_bandwidth / lc->framerate);
125  lrc->max_frame_bandwidth = cpi->rc.max_frame_bandwidth;
126  // Update the average layer frame size (non-cumulative per-frame-bw).
127  if (layer == 0) {
128    lc->avg_frame_size = lrc->av_per_frame_bandwidth;
129  } else {
130    const double prev_layer_framerate =
131        oxcf->framerate / oxcf->ts_rate_decimator[layer - 1];
132    const int prev_layer_target_bandwidth =
133        oxcf->ts_target_bitrate[layer - 1] * 1000;
134    lc->avg_frame_size =
135        (int)((lc->target_bandwidth - prev_layer_target_bandwidth) /
136              (lc->framerate - prev_layer_framerate));
137  }
138}
139
140void vp9_update_spatial_layer_framerate(VP9_COMP *const cpi, double framerate) {
141  const VP9_CONFIG *const oxcf = &cpi->oxcf;
142  LAYER_CONTEXT *const lc = get_layer_context(&cpi->svc);
143  RATE_CONTROL *const lrc = &lc->rc;
144
145  lc->framerate = framerate;
146  lrc->av_per_frame_bandwidth = (int)(lc->target_bandwidth / lc->framerate);
147  lrc->min_frame_bandwidth = (int)(lrc->av_per_frame_bandwidth *
148                                   oxcf->two_pass_vbrmin_section / 100);
149  lrc->max_frame_bandwidth = (int)(((int64_t)lrc->av_per_frame_bandwidth *
150                                   oxcf->two_pass_vbrmax_section) / 100);
151  lrc->max_gf_interval = 16;
152
153  lrc->static_scene_max_gf_interval = cpi->key_frame_frequency >> 1;
154
155  if (oxcf->play_alternate && oxcf->lag_in_frames) {
156    if (lrc->max_gf_interval > oxcf->lag_in_frames - 1)
157      lrc->max_gf_interval = oxcf->lag_in_frames - 1;
158
159    if (lrc->static_scene_max_gf_interval > oxcf->lag_in_frames - 1)
160      lrc->static_scene_max_gf_interval = oxcf->lag_in_frames - 1;
161  }
162
163  if (lrc->max_gf_interval > lrc->static_scene_max_gf_interval)
164    lrc->max_gf_interval = lrc->static_scene_max_gf_interval;
165}
166
167void vp9_restore_layer_context(VP9_COMP *const cpi) {
168  LAYER_CONTEXT *const lc = get_layer_context(&cpi->svc);
169  const int old_frame_since_key = cpi->rc.frames_since_key;
170  const int old_frame_to_key = cpi->rc.frames_to_key;
171
172  cpi->rc = lc->rc;
173  cpi->twopass = lc->twopass;
174  cpi->oxcf.target_bandwidth = lc->target_bandwidth;
175  cpi->oxcf.starting_buffer_level = lc->starting_buffer_level;
176  cpi->oxcf.optimal_buffer_level = lc->optimal_buffer_level;
177  cpi->oxcf.maximum_buffer_size = lc->maximum_buffer_size;
178  cpi->output_framerate = lc->framerate;
179  // Reset the frames_since_key and frames_to_key counters to their values
180  // before the layer restore. Keep these defined for the stream (not layer).
181  if (cpi->svc.number_temporal_layers > 1) {
182    cpi->rc.frames_since_key = old_frame_since_key;
183    cpi->rc.frames_to_key = old_frame_to_key;
184  }
185}
186
187void vp9_save_layer_context(VP9_COMP *const cpi) {
188  const VP9_CONFIG *const oxcf = &cpi->oxcf;
189  LAYER_CONTEXT *const lc = get_layer_context(&cpi->svc);
190
191  lc->rc = cpi->rc;
192  lc->twopass = cpi->twopass;
193  lc->target_bandwidth = (int)oxcf->target_bandwidth;
194  lc->starting_buffer_level = oxcf->starting_buffer_level;
195  lc->optimal_buffer_level = oxcf->optimal_buffer_level;
196  lc->maximum_buffer_size = oxcf->maximum_buffer_size;
197  lc->framerate = cpi->output_framerate;
198}
199
200void vp9_init_second_pass_spatial_svc(VP9_COMP *cpi) {
201  int i;
202  for (i = 0; i < cpi->svc.number_spatial_layers; ++i) {
203    struct twopass_rc *const twopass = &cpi->svc.layer_context[i].twopass;
204
205    cpi->svc.spatial_layer_id = i;
206    vp9_init_second_pass(cpi);
207
208    twopass->total_stats.spatial_layer_id = i;
209    twopass->total_left_stats.spatial_layer_id = i;
210  }
211  cpi->svc.spatial_layer_id = 0;
212}
213