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
13#include "./vpx_config.h"
14
15#include "vp9/common/vp9_common.h"
16
17#include "vp9/encoder/vp9_extend.h"
18#include "vp9/encoder/vp9_lookahead.h"
19#include "vp9/encoder/vp9_onyx_int.h"
20
21struct lookahead_ctx {
22  unsigned int max_sz;         /* Absolute size of the queue */
23  unsigned int sz;             /* Number of buffers currently in the queue */
24  unsigned int read_idx;       /* Read index */
25  unsigned int write_idx;      /* Write index */
26  struct lookahead_entry *buf; /* Buffer list */
27};
28
29
30/* Return the buffer at the given absolute index and increment the index */
31static struct lookahead_entry *pop(struct lookahead_ctx *ctx,
32                                   unsigned int *idx) {
33  unsigned int index = *idx;
34  struct lookahead_entry *buf = ctx->buf + index;
35
36  assert(index < ctx->max_sz);
37  if (++index >= ctx->max_sz)
38    index -= ctx->max_sz;
39  *idx = index;
40  return buf;
41}
42
43
44void vp9_lookahead_destroy(struct lookahead_ctx *ctx) {
45  if (ctx) {
46    if (ctx->buf) {
47      unsigned int i;
48
49      for (i = 0; i < ctx->max_sz; i++)
50        vp9_free_frame_buffer(&ctx->buf[i].img);
51      free(ctx->buf);
52    }
53    free(ctx);
54  }
55}
56
57
58struct lookahead_ctx *vp9_lookahead_init(unsigned int width,
59                                         unsigned int height,
60                                         unsigned int subsampling_x,
61                                         unsigned int subsampling_y,
62                                         unsigned int depth) {
63  struct lookahead_ctx *ctx = NULL;
64
65  // Clamp the lookahead queue depth
66  depth = clamp(depth, 1, MAX_LAG_BUFFERS);
67
68  // Allocate memory to keep previous source frames available.
69  depth += MAX_PRE_FRAMES;
70
71  // Allocate the lookahead structures
72  ctx = calloc(1, sizeof(*ctx));
73  if (ctx) {
74    unsigned int i;
75    ctx->max_sz = depth;
76    ctx->buf = calloc(depth, sizeof(*ctx->buf));
77    if (!ctx->buf)
78      goto bail;
79    for (i = 0; i < depth; i++)
80      if (vp9_alloc_frame_buffer(&ctx->buf[i].img,
81                                 width, height, subsampling_x, subsampling_y,
82                                 VP9_ENC_BORDER_IN_PIXELS))
83        goto bail;
84  }
85  return ctx;
86 bail:
87  vp9_lookahead_destroy(ctx);
88  return NULL;
89}
90
91#define USE_PARTIAL_COPY 0
92
93int vp9_lookahead_push(struct lookahead_ctx *ctx, YV12_BUFFER_CONFIG   *src,
94                       int64_t ts_start, int64_t ts_end, unsigned int flags) {
95  struct lookahead_entry *buf;
96#if USE_PARTIAL_COPY
97  int row, col, active_end;
98  int mb_rows = (src->y_height + 15) >> 4;
99  int mb_cols = (src->y_width + 15) >> 4;
100#endif
101
102  if (ctx->sz + 1  + MAX_PRE_FRAMES > ctx->max_sz)
103    return 1;
104  ctx->sz++;
105  buf = pop(ctx, &ctx->write_idx);
106
107#if USE_PARTIAL_COPY
108  // TODO(jkoleszar): This is disabled for now, as
109  // vp9_copy_and_extend_frame_with_rect is not subsampling/alpha aware.
110
111  // Only do this partial copy if the following conditions are all met:
112  // 1. Lookahead queue has has size of 1.
113  // 2. Active map is provided.
114  // 3. This is not a key frame, golden nor altref frame.
115  if (ctx->max_sz == 1 && active_map && !flags) {
116    for (row = 0; row < mb_rows; ++row) {
117      col = 0;
118
119      while (1) {
120        // Find the first active macroblock in this row.
121        for (; col < mb_cols; ++col) {
122          if (active_map[col])
123            break;
124        }
125
126        // No more active macroblock in this row.
127        if (col == mb_cols)
128          break;
129
130        // Find the end of active region in this row.
131        active_end = col;
132
133        for (; active_end < mb_cols; ++active_end) {
134          if (!active_map[active_end])
135            break;
136        }
137
138        // Only copy this active region.
139        vp9_copy_and_extend_frame_with_rect(src, &buf->img,
140                                            row << 4,
141                                            col << 4, 16,
142                                            (active_end - col) << 4);
143
144        // Start again from the end of this active region.
145        col = active_end;
146      }
147
148      active_map += mb_cols;
149    }
150  } else {
151    vp9_copy_and_extend_frame(src, &buf->img);
152  }
153#else
154  // Partial copy not implemented yet
155  vp9_copy_and_extend_frame(src, &buf->img);
156#endif
157
158  buf->ts_start = ts_start;
159  buf->ts_end = ts_end;
160  buf->flags = flags;
161  return 0;
162}
163
164
165struct lookahead_entry *vp9_lookahead_pop(struct lookahead_ctx *ctx,
166                                          int drain) {
167  struct lookahead_entry *buf = NULL;
168
169  if (ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
170    buf = pop(ctx, &ctx->read_idx);
171    ctx->sz--;
172  }
173  return buf;
174}
175
176
177struct lookahead_entry *vp9_lookahead_peek(struct lookahead_ctx *ctx,
178                                           int index) {
179  struct lookahead_entry *buf = NULL;
180
181  if (index >= 0) {
182    // Forward peek
183    if (index < (int)ctx->sz) {
184      index += ctx->read_idx;
185      if (index >= (int)ctx->max_sz)
186        index -= ctx->max_sz;
187      buf = ctx->buf + index;
188    }
189  } else if (index < 0) {
190    // Backward peek
191    if (-index <= MAX_PRE_FRAMES) {
192      index += ctx->read_idx;
193      if (index < 0)
194        index += ctx->max_sz;
195      buf = ctx->buf + index;
196    }
197  }
198
199  return buf;
200}
201
202unsigned int vp9_lookahead_depth(struct lookahead_ctx *ctx) {
203  return ctx->sz;
204}
205