ref: c1f77a3689a6cf5e95e1c1ae35d76f4f171f5ef3
dir: /vp9/encoder/vp9_lookahead.h/
/*
* Copyright (c) 2011 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VPX_VP9_ENCODER_VP9_LOOKAHEAD_H_
#define VPX_VP9_ENCODER_VP9_LOOKAHEAD_H_
#include "vpx_scale/yv12config.h"
#include "vpx/vpx_encoder.h"
#include "vpx/vpx_integer.h"
#ifdef __cplusplus
extern "C" {
#endif
#define MAX_LAG_BUFFERS 25
struct lookahead_entry {
YV12_BUFFER_CONFIG img;
int64_t ts_start;
int64_t ts_end;
int show_idx; /*The show_idx of this frame*/
vpx_enc_frame_flags_t flags;
};
// The max of past frames we want to keep in the queue.
#define MAX_PRE_FRAMES 1
struct lookahead_ctx {
int max_sz; /* Absolute size of the queue */
int sz; /* Number of buffers currently in the queue */
int read_idx; /* Read index */
int write_idx; /* Write index */
int next_show_idx; /* The show_idx that will be assigned to the next frame
being pushed in the queue*/
struct lookahead_entry *buf; /* Buffer list */
};
/**\brief Initializes the lookahead stage
*
* The lookahead stage is a queue of frame buffers on which some analysis
* may be done when buffers are enqueued.
*/
struct lookahead_ctx *vp9_lookahead_init(unsigned int width,
unsigned int height,
unsigned int subsampling_x,
unsigned int subsampling_y,
#if CONFIG_VP9_HIGHBITDEPTH
int use_highbitdepth,
#endif
unsigned int depth);
/**\brief Destroys the lookahead stage
*/
void vp9_lookahead_destroy(struct lookahead_ctx *ctx);
/**\brief Check if lookahead is full
*
* \param[in] ctx Pointer to the lookahead context
*
* Return 1 if lookahead is full, otherwise return 0.
*/
int vp9_lookahead_full(const struct lookahead_ctx *ctx);
/**\brief Return the next_show_idx
*
* \param[in] ctx Pointer to the lookahead context
*
* Return the show_idx that will be assigned to the next
* frame pushed by vp9_lookahead_push()
*/
int vp9_lookahead_next_show_idx(const struct lookahead_ctx *ctx);
/**\brief Enqueue a source buffer
*
* This function will copy the source image into a new framebuffer with
* the expected stride/border.
*
* \param[in] ctx Pointer to the lookahead context
* \param[in] src Pointer to the image to enqueue
* \param[in] ts_start Timestamp for the start of this frame
* \param[in] ts_end Timestamp for the end of this frame
* \param[in] flags Flags set on this frame
*/
int 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);
/**\brief Get the next source buffer to encode
*
*
* \param[in] ctx Pointer to the lookahead context
* \param[in] drain Flag indicating the buffer should be drained
* (return a buffer regardless of the current queue depth)
*
* \retval NULL, if drain set and queue is empty
* \retval NULL, if drain not set and queue not of the configured depth
*/
struct lookahead_entry *vp9_lookahead_pop(struct lookahead_ctx *ctx, int drain);
/**\brief Get a future source buffer to encode
*
* \param[in] ctx Pointer to the lookahead context
* \param[in] index Index of the frame to be returned, 0 == next frame
*
* \retval NULL, if no buffer exists at the specified index
*/
struct lookahead_entry *vp9_lookahead_peek(struct lookahead_ctx *ctx,
int index);
/**\brief Get the number of frames currently in the lookahead queue
*
* \param[in] ctx Pointer to the lookahead context
*/
unsigned int vp9_lookahead_depth(struct lookahead_ctx *ctx);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // VPX_VP9_ENCODER_VP9_LOOKAHEAD_H_