xref: /aosp_15_r20/external/libvpx/vp9/encoder/vp9_lookahead.c (revision fb1b10ab9aebc7c7068eedab379b749d7e3900be)
1 /*
2  *  Copyright (c) 2011 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 #include <assert.h>
11 #include <stdlib.h>
12 #include <string.h>
13 
14 #include "./vpx_config.h"
15 
16 #include "vp9/common/vp9_common.h"
17 
18 #include "vp9/encoder/vp9_encoder.h"
19 #include "vp9/encoder/vp9_extend.h"
20 #include "vp9/encoder/vp9_lookahead.h"
21 
22 /* Return the buffer at the given absolute index and increment the index */
pop(struct lookahead_ctx * ctx,int * idx)23 static struct lookahead_entry *pop(struct lookahead_ctx *ctx, int *idx) {
24   int index = *idx;
25   struct lookahead_entry *buf = ctx->buf + index;
26 
27   assert(index < ctx->max_sz);
28   if (++index >= ctx->max_sz) index -= ctx->max_sz;
29   *idx = index;
30   return buf;
31 }
32 
vp9_lookahead_destroy(struct lookahead_ctx * ctx)33 void vp9_lookahead_destroy(struct lookahead_ctx *ctx) {
34   if (ctx) {
35     if (ctx->buf) {
36       int i;
37 
38       for (i = 0; i < ctx->max_sz; i++) vpx_free_frame_buffer(&ctx->buf[i].img);
39       free(ctx->buf);
40     }
41     free(ctx);
42   }
43 }
44 
vp9_lookahead_init(unsigned int width,unsigned int height,unsigned int subsampling_x,unsigned int subsampling_y,int use_highbitdepth,unsigned int depth)45 struct lookahead_ctx *vp9_lookahead_init(unsigned int width,
46                                          unsigned int height,
47                                          unsigned int subsampling_x,
48                                          unsigned int subsampling_y,
49 #if CONFIG_VP9_HIGHBITDEPTH
50                                          int use_highbitdepth,
51 #endif
52                                          unsigned int depth) {
53   struct lookahead_ctx *ctx = NULL;
54 
55   // Clamp the lookahead queue depth
56   depth = clamp(depth, 1, MAX_LAG_BUFFERS);
57 
58   // Allocate memory to keep previous source frames available.
59   depth += MAX_PRE_FRAMES;
60 
61   // Allocate the lookahead structures
62   ctx = calloc(1, sizeof(*ctx));
63   if (ctx) {
64     const int legacy_byte_alignment = 0;
65     unsigned int i;
66     ctx->max_sz = depth;
67     ctx->buf = calloc(depth, sizeof(*ctx->buf));
68     ctx->next_show_idx = 0;
69     if (!ctx->buf) goto bail;
70     for (i = 0; i < depth; i++)
71       if (vpx_alloc_frame_buffer(
72               &ctx->buf[i].img, width, height, subsampling_x, subsampling_y,
73 #if CONFIG_VP9_HIGHBITDEPTH
74               use_highbitdepth,
75 #endif
76               VP9_ENC_BORDER_IN_PIXELS, legacy_byte_alignment))
77         goto bail;
78   }
79   return ctx;
80 bail:
81   vp9_lookahead_destroy(ctx);
82   return NULL;
83 }
84 
vp9_lookahead_full(const struct lookahead_ctx * ctx)85 int vp9_lookahead_full(const struct lookahead_ctx *ctx) {
86   return ctx->sz + 1 + MAX_PRE_FRAMES > ctx->max_sz;
87 }
88 
vp9_lookahead_next_show_idx(const struct lookahead_ctx * ctx)89 int vp9_lookahead_next_show_idx(const struct lookahead_ctx *ctx) {
90   return ctx->next_show_idx;
91 }
92 
vp9_lookahead_push(struct lookahead_ctx * ctx,YV12_BUFFER_CONFIG * src,int64_t ts_start,int64_t ts_end,int use_highbitdepth,vpx_enc_frame_flags_t flags)93 int vp9_lookahead_push(struct lookahead_ctx *ctx, YV12_BUFFER_CONFIG *src,
94                        int64_t ts_start, int64_t ts_end, int use_highbitdepth,
95                        vpx_enc_frame_flags_t flags) {
96   struct lookahead_entry *buf;
97   int width = src->y_crop_width;
98   int height = src->y_crop_height;
99   int uv_width = src->uv_crop_width;
100   int uv_height = src->uv_crop_height;
101   int subsampling_x = src->subsampling_x;
102   int subsampling_y = src->subsampling_y;
103   int larger_dimensions, new_dimensions;
104 #if !CONFIG_VP9_HIGHBITDEPTH
105   (void)use_highbitdepth;
106   assert(use_highbitdepth == 0);
107 #endif
108 
109   if (vp9_lookahead_full(ctx)) return 1;
110   ctx->sz++;
111   buf = pop(ctx, &ctx->write_idx);
112 
113   new_dimensions = width != buf->img.y_crop_width ||
114                    height != buf->img.y_crop_height ||
115                    uv_width != buf->img.uv_crop_width ||
116                    uv_height != buf->img.uv_crop_height;
117   larger_dimensions =
118       width > buf->img.y_crop_width || height > buf->img.y_crop_height ||
119       uv_width > buf->img.uv_crop_width || uv_height > buf->img.uv_crop_height;
120   assert(!larger_dimensions || new_dimensions);
121 
122   if (larger_dimensions) {
123     YV12_BUFFER_CONFIG new_img;
124     memset(&new_img, 0, sizeof(new_img));
125     if (vpx_alloc_frame_buffer(&new_img, width, height, subsampling_x,
126                                subsampling_y,
127 #if CONFIG_VP9_HIGHBITDEPTH
128                                use_highbitdepth,
129 #endif
130                                VP9_ENC_BORDER_IN_PIXELS, 0))
131       return 1;
132     vpx_free_frame_buffer(&buf->img);
133     buf->img = new_img;
134   } else if (new_dimensions) {
135     buf->img.y_width = src->y_width;
136     buf->img.y_height = src->y_height;
137     buf->img.uv_width = src->uv_width;
138     buf->img.uv_height = src->uv_height;
139     buf->img.y_crop_width = src->y_crop_width;
140     buf->img.y_crop_height = src->y_crop_height;
141     buf->img.uv_crop_width = src->uv_crop_width;
142     buf->img.uv_crop_height = src->uv_crop_height;
143     buf->img.subsampling_x = src->subsampling_x;
144     buf->img.subsampling_y = src->subsampling_y;
145   }
146   vp9_copy_and_extend_frame(src, &buf->img);
147 
148   buf->ts_start = ts_start;
149   buf->ts_end = ts_end;
150   buf->flags = flags;
151   buf->show_idx = ctx->next_show_idx;
152   ++ctx->next_show_idx;
153   return 0;
154 }
155 
vp9_lookahead_pop(struct lookahead_ctx * ctx,int drain)156 struct lookahead_entry *vp9_lookahead_pop(struct lookahead_ctx *ctx,
157                                           int drain) {
158   struct lookahead_entry *buf = NULL;
159 
160   if (ctx && ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
161     buf = pop(ctx, &ctx->read_idx);
162     ctx->sz--;
163   }
164   return buf;
165 }
166 
vp9_lookahead_peek(struct lookahead_ctx * ctx,int index)167 struct lookahead_entry *vp9_lookahead_peek(struct lookahead_ctx *ctx,
168                                            int index) {
169   struct lookahead_entry *buf = NULL;
170 
171   if (index >= 0) {
172     // Forward peek
173     if (index < ctx->sz) {
174       index += ctx->read_idx;
175       if (index >= ctx->max_sz) index -= ctx->max_sz;
176       buf = ctx->buf + index;
177     }
178   } else if (index < 0) {
179     // Backward peek
180     if (-index <= MAX_PRE_FRAMES) {
181       index += ctx->read_idx;
182       if (index < 0) index += ctx->max_sz;
183       buf = ctx->buf + index;
184     }
185   }
186 
187   return buf;
188 }
189 
vp9_lookahead_depth(struct lookahead_ctx * ctx)190 unsigned int vp9_lookahead_depth(struct lookahead_ctx *ctx) { return ctx->sz; }
191