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
11#ifndef VP9_ENCODER_VP9_LOOKAHEAD_H_
12#define VP9_ENCODER_VP9_LOOKAHEAD_H_
13
14#include "vpx_scale/yv12config.h"
15#include "vpx/vpx_integer.h"
16
17#ifdef __cplusplus
18extern "C" {
19#endif
20
21#define MAX_LAG_BUFFERS 25
22
23// The max of past frames we want to keep in the queue.
24#define MAX_PRE_FRAMES 1
25
26struct lookahead_entry {
27  YV12_BUFFER_CONFIG  img;
28  int64_t             ts_start;
29  int64_t             ts_end;
30  unsigned int        flags;
31};
32
33
34struct lookahead_ctx;
35
36/**\brief Initializes the lookahead stage
37 *
38 * The lookahead stage is a queue of frame buffers on which some analysis
39 * may be done when buffers are enqueued.
40 */
41struct lookahead_ctx *vp9_lookahead_init(unsigned int width,
42                                         unsigned int height,
43                                         unsigned int subsampling_x,
44                                         unsigned int subsampling_y,
45                                         unsigned int depth);
46
47
48/**\brief Destroys the lookahead stage
49 */
50void vp9_lookahead_destroy(struct lookahead_ctx *ctx);
51
52
53/**\brief Enqueue a source buffer
54 *
55 * This function will copy the source image into a new framebuffer with
56 * the expected stride/border.
57 *
58 * If active_map is non-NULL and there is only one frame in the queue, then copy
59 * only active macroblocks.
60 *
61 * \param[in] ctx         Pointer to the lookahead context
62 * \param[in] src         Pointer to the image to enqueue
63 * \param[in] ts_start    Timestamp for the start of this frame
64 * \param[in] ts_end      Timestamp for the end of this frame
65 * \param[in] flags       Flags set on this frame
66 * \param[in] active_map  Map that specifies which macroblock is active
67 */
68int vp9_lookahead_push(struct lookahead_ctx *ctx, YV12_BUFFER_CONFIG *src,
69                       int64_t ts_start, int64_t ts_end, unsigned int flags);
70
71
72/**\brief Get the next source buffer to encode
73 *
74 *
75 * \param[in] ctx       Pointer to the lookahead context
76 * \param[in] drain     Flag indicating the buffer should be drained
77 *                      (return a buffer regardless of the current queue depth)
78 *
79 * \retval NULL, if drain set and queue is empty
80 * \retval NULL, if drain not set and queue not of the configured depth
81 */
82struct lookahead_entry *vp9_lookahead_pop(struct lookahead_ctx *ctx,
83                                          int drain);
84
85
86/**\brief Get a future source buffer to encode
87 *
88 * \param[in] ctx       Pointer to the lookahead context
89 * \param[in] index     Index of the frame to be returned, 0 == next frame
90 *
91 * \retval NULL, if no buffer exists at the specified index
92 */
93struct lookahead_entry *vp9_lookahead_peek(struct lookahead_ctx *ctx,
94                                           int index);
95
96
97/**\brief Get the number of frames currently in the lookahead queue
98 *
99 * \param[in] ctx       Pointer to the lookahead context
100 */
101unsigned int vp9_lookahead_depth(struct lookahead_ctx *ctx);
102
103#ifdef __cplusplus
104}  // extern "C"
105#endif
106
107#endif  // VP9_ENCODER_VP9_LOOKAHEAD_H_
108