av1/encoder/ratectrl.h - avm - Git at Google

 /*
  * Copyright (c) 2021, Alliance for Open Media. All rights reserved
  *
  * This source code is subject to the terms of the BSD 3-Clause Clear License
  * and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
  * License was not distributed with this source code in the LICENSE file, you
  * can obtain it at aomedia.org/license/software-license/bsd-3-c-c/.  If the
  * Alliance for Open Media Patent License 1.0 was not distributed with this
  * source code in the PATENTS file, you can obtain it at
  * aomedia.org/license/patent-license/.
  */

 #ifndef AOM_AV1_ENCODER_RATECTRL_H_
 #define AOM_AV1_ENCODER_RATECTRL_H_

 #include "aom/aom_codec.h"
 #include "aom/aom_integer.h"

 #include "aom_ports/mem.h"

 #include "av1/common/av1_common_int.h"
 #include "av1/common/blockd.h"

 #ifdef __cplusplus
 extern "C" {
 #endif

 /*!\cond */

 // Bits Per MB at different Q (Multiplied by 512)
 #define BPER_MB_NORMBITS 9

 // Use this macro to turn on/off use of alt-refs in one-pass mode.
 #define USE_ALTREF_FOR_ONE_PASS 1

 // Threshold used to define if a KF group is static (e.g. a slide show).
 // Essentially, this means that no frame in the group has more than 1% of MBs
 // that are not marked as coded with 0,0 motion in the first pass.
 #define STATIC_KF_GROUP_THRESH 99
 #define STATIC_KF_GROUP_FLOAT_THRESH 0.99

 // The maximum duration of a GF group that is static (e.g. a slide show).
 #define MAX_STATIC_GF_GROUP_LENGTH 250

 #define MIN_GF_INTERVAL 4
 #define MAX_GF_INTERVAL 32
 #define MAX_GF_LENGTH_LAP MAX_GF_INTERVAL

 #define MAX_NUM_GF_INTERVALS 15

 #define MAX_ARF_LAYERS 6
 // #define STRICT_RC

 typedef struct {
   int resize_width;
   int resize_height;
   uint8_t superres_denom;
 } size_params_type;

 enum {
   INTER_NORMAL,
   GF_ARF_LOW,
   GF_ARF_STD,
   KF_STD,
   RATE_FACTOR_LEVELS
 } UENUM1BYTE(RATE_FACTOR_LEVEL);

 enum {
   KF_UPDATE,
   LF_UPDATE,
   GF_UPDATE,
   ARF_UPDATE,
   OVERLAY_UPDATE,
   INTNL_OVERLAY_UPDATE,  // Internal Overlay Frame
   INTNL_ARF_UPDATE,      // Internal Altref Frame
   KFFLT_UPDATE,          // Filtered KF w/ overlay update
   KFFLT_OVERLAY_UPDATE,  // Overlay frame for filtered keyframe
   FRAME_UPDATE_TYPES
 } UENUM1BYTE(FRAME_UPDATE_TYPE);

 typedef enum {
   NO_RESIZE = 0,
   DOWN_THREEFOUR = 1,  // From orig to 3/4.
   DOWN_ONEHALF = 2,    // From orig or 3/4 to 1/2.
   UP_THREEFOUR = -1,   // From 1/2 to 3/4.
   UP_ORIG = -2,        // From 1/2 or 3/4 to orig.
 } RESIZE_ACTION;

 typedef enum { ORIG = 0, THREE_QUARTER = 1, ONE_HALF = 2 } RESIZE_STATE;

 /*!\endcond */
 /*!
  * \brief  Rate Control parameters and status
  */
 typedef struct {
   // Rate targetting variables

   /*!
    * Baseline target rate for frame before adjustment for previous under or
    * over shoot.
    */
   int base_frame_target;
   /*!
    * Target rate for frame after adjustment for previous under or over shoot.
    */
   int this_frame_target;  // Actual frame target after rc adjustment.

   /*!
    * Target bit budget for the current GF / ARF group of frame.
    */
   int64_t gf_group_bits;

   /*!
    * Projected size for current frame
    */
   int projected_frame_size;

   /*!
    * Super block rate target used with some adaptive quantization strategies.
    */
   int sb64_target_rate;

   /*!
    * Q used on last encoded frame of the given type.
    */
   int last_q[FRAME_TYPES];

   /*!
    * Q used for last boosted (non leaf) frame (GF/KF/ARF)
    */
   int last_boosted_qindex;

   /*!
    * Q used for last boosted (non leaf) frame
    */
   int last_kf_qindex;

   /*!
    * Boost factor used to calculate the extra bits allocated to ARFs and GFs
    */
   int gfu_boost;
   /*!
    * Boost factor used to calculate the extra bits allocated to the key frame
    */
   int kf_boost;

   /*!
    * Correction factors used to adjust the q estimate for a given target rate
    * in the encode loop.
    */
   double rate_correction_factors[RATE_FACTOR_LEVELS];

   /*!
    * Number of frames since the last ARF / GF.
    */
   int frames_since_golden;

   /*!
    * Number of frames till the next ARF / GF is due.
    */
   int frames_till_gf_update_due;

   /*!
    * Number of determined gf groups left
    */
   int intervals_till_gf_calculate_due;

   /*!
    * Stores the determined gf group lengths for a set of gf groups
    */
   int gf_intervals[MAX_NUM_GF_INTERVALS];

   /*!
    * The current group's index into gf_intervals[]
    */
   int cur_gf_index;

   /*!\cond */
   int min_gf_interval;
   int max_gf_interval;
   int static_scene_max_gf_interval;
   int baseline_gf_interval;
   int constrained_gf_group;
   /*!\endcond */
   /*!
    * Frames before the next key frame
    */
   int frames_to_key;
   /*!\cond */
   int frames_since_key;
   int this_key_frame_forced;
   int next_key_frame_forced;
   int is_src_frame_alt_ref;
   int sframe_due;

   int high_source_sad;
   uint64_t avg_source_sad;

   int avg_frame_bandwidth;  // Average frame size target for clip
   int min_frame_bandwidth;  // Minimum allocation used for any frame
   int max_frame_bandwidth;  // Maximum burst rate allowed for a frame.
   int prev_avg_frame_bandwidth;

   int ni_av_qi;
   int ni_tot_qi;
   int ni_frames;
   int avg_frame_qindex[FRAME_TYPES];
   double tot_q;
   double avg_q;

   int64_t buffer_level;
   int64_t bits_off_target;
   int64_t vbr_bits_off_target;
   int64_t vbr_bits_off_target_fast;

   int decimation_factor;
   int decimation_count;

   int rolling_target_bits;
   int rolling_actual_bits;

   int long_rolling_target_bits;
   int long_rolling_actual_bits;

   int rate_error_estimate;

   int64_t total_actual_bits;
   int64_t total_target_bits;
   int64_t total_target_vs_actual;

   /*!\endcond */
   /*!
    * User specified maximum Q allowed for current frame
    */
   int worst_quality;
   /*!
    * User specified minimum Q allowed for current frame
    */
   int best_quality;

   /*!
    * Initial buffuer level in ms for CBR / low delay encoding
    */
   int64_t starting_buffer_level;
   /*!
    * Optimum / target buffuer level in ms for CBR / low delay encoding
    */
   int64_t optimal_buffer_level;
   /*!
    * Maximum target buffuer level in ms for CBR / low delay encoding
    */
   int64_t maximum_buffer_size;
   /*!\cond */

   // rate control history for last frame(1) and the frame before(2).
   // -1: undershot
   //  1: overshoot
   //  0: not initialized.
   int rc_1_frame;
   int rc_2_frame;
   int q_1_frame;
   int q_2_frame;

   float_t arf_boost_factor;

   /*!\endcond */
   /*!
    * Q index used for frame(s) at pyramid level 1, such as an ALTREF frame.
    */
   int level1_qp;
   /*!
    * Proposed maximum alloed Q for current frame
    */
   int active_worst_quality;
   /*!
    * Proposed minimum allowed Q different layers in a coding pyramid
    */
   int active_best_quality[MAX_ARF_LAYERS + 1];

   /*!\cond */
   int base_layer_qp;

   // Total number of stats used only for kf_boost calculation.
   int num_stats_used_for_kf_boost;
   // Total number of stats used only for gfu_boost calculation.
   int num_stats_used_for_gfu_boost;
   // Total number of stats required by gfu_boost calculation.
   int num_stats_required_for_gfu_boost;
   int next_is_fwd_key;
   int enable_scenecut_detection;
   int use_arf_in_this_kf_group;
   // Track amount of low motion in scene
   int avg_frame_low_motion;

   // For dynamic resize, 1 pass cbr.
   RESIZE_STATE resize_state;
   int resize_avg_qp;
   int resize_buffer_underflow;
   int resize_count;
   /*!\endcond */
 } RATE_CONTROL;

 /*!\cond */

 struct AV1_COMP;
 struct AV1EncoderConfig;

 void av1_rc_init(const struct AV1EncoderConfig *oxcf, int pass,
                  RATE_CONTROL *rc);

 int av1_estimate_bits_at_q(FRAME_TYPE frame_kind, int q, int mbs,
                            double correction_factor, aom_bit_depth_t bit_depth,
                            const int is_screen_content_type);

 double av1_convert_qindex_to_q(int qindex, aom_bit_depth_t bit_depth);

 void av1_rc_init_minq_luts(void);

 int av1_rc_get_default_min_gf_interval(int width, int height, double framerate);
 // Note av1_rc_get_default_max_gf_interval() requires the min_gf_interval to
 // be passed in to ensure that the max_gf_interval returned is at least as bis
 // as that.
 int av1_rc_get_default_max_gf_interval(double framerate, int min_gf_interval);

 // Generally at the high level, the following flow is expected
 // to be enforced for rate control:
 // First call per frame, one of:
 //   av1_rc_get_first_pass_params()
 //   av1_rc_get_second_pass_params()
 // depending on the usage to set the rate control encode parameters desired.
 //
 // Then, call encode_frame_to_data_rate() to perform the
 // actual encode. This function will in turn call encode_frame()
 // one or more times, followed by one of:
 //   av1_rc_postencode_update()
 //   av1_rc_postencode_update_drop_frame()
 //
 // The majority of rate control parameters are only expected
 // to be set in the av1_rc_get_..._params() functions and
 // updated during the av1_rc_postencode_update...() functions.
 // The only exceptions are av1_rc_drop_frame() and
 // av1_rc_update_rate_correction_factors() functions.

 // Functions to set parameters for encoding before the actual
 // encode_frame_to_data_rate() function.
 struct EncodeFrameParams;

 // Post encode update of the rate control parameters based
 // on bytes used
 void av1_rc_postencode_update(struct AV1_COMP *cpi, uint64_t bytes_used);
 // Post encode update of the rate control parameters for dropped frames
 void av1_rc_postencode_update_drop_frame(struct AV1_COMP *cpi);

 /*!\endcond */
 /*!\brief Updates the rate correction factor linking Q to output bits
  *
  * This function updates the Q rate correction factor after an encode
  * cycle depending on whether we overshot or undershot the target rate.
  *
  * \ingroup rate_control
  * \param[in]   cpi                   Top level encoder instance structure
  * \param[in]   width                 Frame width
  * \param[in]   height                Frame height
  *
  * \return None but updates the relevant rate correction factor in cpi->rc
  */
 void av1_rc_update_rate_correction_factors(struct AV1_COMP *cpi, int width,
                                            int height);
 /*!\cond */

 // Decide if we should drop this frame: For 1-pass CBR.
 // Changes only the decimation count in the rate control structure
 int av1_rc_drop_frame(struct AV1_COMP *cpi);

 // Computes frame size bounds.
 void av1_rc_compute_frame_size_bounds(const struct AV1_COMP *cpi,
                                       int this_frame_target,
                                       int *frame_under_shoot_limit,
                                       int *frame_over_shoot_limit);

 /*!\endcond */

 /*!\brief Picks q and q bounds given the rate control parameters in \c cpi->rc.
  *
  * \ingroup rate_control
  * \param[in]       cpi          Top level encoder structure
  * \param[in,out]   rc           Top level rate control structure
  * \param[in]       width        Coded frame width
  * \param[in]       height       Coded frame height
  * \param[in]       gf_index     Index of this frame in the golden frame group
  * \param[out]      bottom_index Bottom bound for q index (best quality)
  * \param[out]      top_index    Top bound for q index (worst quality)
  * \return Returns selected q index to be used for encoding this frame.
  * Also, updates \c rc->level1_qp.
  */
 int av1_rc_pick_q_and_bounds(const struct AV1_COMP *cpi, RATE_CONTROL *rc,
                              int width, int height, int gf_index,
                              int *bottom_index, int *top_index);

 /*!\brief Estimates q to achieve a target bits per frame
  *
  * \ingroup rate_control
  * \param[in]   cpi                   Top level encoder instance structure
  * \param[in]   target_bits_per_frame Frame rate target
  * \param[in]   active_worst_quality  Max Q allowed
  * \param[in]   active_best_quality   Min Q allowed
  * \param[in]   width                 Frame width
  * \param[in]   height                Frame height
  *
  * \return Returns a q index value
  */
 int av1_rc_regulate_q(const struct AV1_COMP *cpi, int target_bits_per_frame,
                       int active_best_quality, int active_worst_quality,
                       int width, int height);

 /*!\cond */
 // Estimates bits per mb for a given qindex and correction factor.
 int av1_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
                        double correction_factor, aom_bit_depth_t bit_depth,
                        const int is_screen_content_type);

 // Clamping utilities for bitrate targets for iframes and pframes.
 int av1_rc_clamp_iframe_target_size(const struct AV1_COMP *const cpi,
                                     int target);
 int av1_rc_clamp_pframe_target_size(const struct AV1_COMP *const cpi,
                                     int target, uint8_t frame_update_type);

 // Find q_index corresponding to desired_q, within [best_qindex, worst_qindex].
 // To be precise, 'q_index' is the smallest integer, for which the corresponding
 // q >= desired_q.
 // If no such q index is found, returns 'worst_qindex'.
 int av1_find_qindex(double desired_q, aom_bit_depth_t bit_depth,
                     int best_qindex, int worst_qindex);

 // Computes a q delta (in "q index" terms) to get from a starting q value
 // to a target q value
 int av1_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget,
                        aom_bit_depth_t bit_depth);

 // Computes a q delta (in "q index" terms) to get from a starting q value
 // to a value that should equate to the given rate ratio.
 int av1_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type,
                                int qindex, double rate_target_ratio,
                                const int is_screen_content_type,
                                aom_bit_depth_t bit_depth);

 int av1_frame_type_qdelta(const struct AV1_COMP *cpi, int q);

 void av1_rc_update_framerate(struct AV1_COMP *cpi, int width, int height);

 void av1_rc_set_gf_interval_range(const struct AV1_COMP *const cpi,
                                   RATE_CONTROL *const rc);

 void av1_set_target_rate(struct AV1_COMP *cpi, int width, int height);

 int av1_resize_one_pass_cbr(struct AV1_COMP *cpi);

 void av1_rc_set_frame_target(struct AV1_COMP *cpi, int target, int width,
                              int height);

 /*!\endcond */
 /*!\brief Calculates how many bits to use for a P frame in one pass vbr
  *
  * \ingroup rate_control
  * \callgraph
  * \callergraph
  *
  * \param[in]       cpi                 Top level encoder structure
  * \param[in]       frame_update_type   Type of frame
  *
  * \return	Returns the target number of bits for this frame.
  */
 int av1_calc_pframe_target_size_one_pass_vbr(
     const struct AV1_COMP *const cpi, FRAME_UPDATE_TYPE frame_update_type);

 /*!\brief Calculates how many bits to use for an i frame in one pass vbr
  *
  * \ingroup rate_control
  * \callgraph
  * \callergraph
  *
  * \param[in]       cpi  Top level encoder structure
  *
  * \return	Returns the target number of bits for this frame.
  */
 int av1_calc_iframe_target_size_one_pass_vbr(const struct AV1_COMP *const cpi);

 /*!\brief Calculates how many bits to use for a P frame in one pass cbr
  *
  * \ingroup rate_control
  * \callgraph
  * \callergraph
  *
  * \param[in]       cpi                 Top level encoder structure
  * \param[in]       frame_update_type   Type of frame
  *
  * \return  Returns the target number of bits for this frame.
  */
 int av1_calc_pframe_target_size_one_pass_cbr(
     const struct AV1_COMP *cpi, FRAME_UPDATE_TYPE frame_update_type);

 /*!\brief Calculates how many bits to use for an i frame in one pass cbr
  *
  * \ingroup rate_control
  * \callgraph
  * \callergraph
  *
  * \param[in]       cpi  Top level encoder structure
  *
  * \return  Returns the target number of bits for this frame.
  */
 int av1_calc_iframe_target_size_one_pass_cbr(const struct AV1_COMP *cpi);

 #ifdef __cplusplus
 }  // extern "C"
 #endif

 #endif  // AOM_AV1_ENCODER_RATECTRL_H_
	/*
	* Copyright (c) 2021, Alliance for Open Media. All rights reserved
	*
	* This source code is subject to the terms of the BSD 3-Clause Clear License
	* and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
	* License was not distributed with this source code in the LICENSE file, you
	* can obtain it at aomedia.org/license/software-license/bsd-3-c-c/. If the
	* Alliance for Open Media Patent License 1.0 was not distributed with this
	* source code in the PATENTS file, you can obtain it at
	* aomedia.org/license/patent-license/.
	*/

	#ifndef AOM_AV1_ENCODER_RATECTRL_H_
	#define AOM_AV1_ENCODER_RATECTRL_H_

	#include "aom/aom_codec.h"
	#include "aom/aom_integer.h"

	#include "aom_ports/mem.h"

	#include "av1/common/av1_common_int.h"
	#include "av1/common/blockd.h"

	#ifdef __cplusplus
	extern "C" {
	#endif

	/!\cond /

	// Bits Per MB at different Q (Multiplied by 512)
	#define BPER_MB_NORMBITS 9

	// Use this macro to turn on/off use of alt-refs in one-pass mode.
	#define USE_ALTREF_FOR_ONE_PASS 1

	// Threshold used to define if a KF group is static (e.g. a slide show).
	// Essentially, this means that no frame in the group has more than 1% of MBs
	// that are not marked as coded with 0,0 motion in the first pass.
	#define STATIC_KF_GROUP_THRESH 99
	#define STATIC_KF_GROUP_FLOAT_THRESH 0.99

	// The maximum duration of a GF group that is static (e.g. a slide show).
	#define MAX_STATIC_GF_GROUP_LENGTH 250

	#define MIN_GF_INTERVAL 4
	#define MAX_GF_INTERVAL 32
	#define MAX_GF_LENGTH_LAP MAX_GF_INTERVAL

	#define MAX_NUM_GF_INTERVALS 15

	#define MAX_ARF_LAYERS 6
	// #define STRICT_RC

	typedef struct {
	int resize_width;
	int resize_height;
	uint8_t superres_denom;
	} size_params_type;

	enum {
	INTER_NORMAL,
	GF_ARF_LOW,
	GF_ARF_STD,
	KF_STD,
	RATE_FACTOR_LEVELS
	} UENUM1BYTE(RATE_FACTOR_LEVEL);

	enum {
	KF_UPDATE,
	LF_UPDATE,
	GF_UPDATE,
	ARF_UPDATE,
	OVERLAY_UPDATE,
	INTNL_OVERLAY_UPDATE, // Internal Overlay Frame
	INTNL_ARF_UPDATE, // Internal Altref Frame
	KFFLT_UPDATE, // Filtered KF w/ overlay update
	KFFLT_OVERLAY_UPDATE, // Overlay frame for filtered keyframe
	FRAME_UPDATE_TYPES
	} UENUM1BYTE(FRAME_UPDATE_TYPE);

	typedef enum {
	NO_RESIZE = 0,
	DOWN_THREEFOUR = 1, // From orig to 3/4.
	DOWN_ONEHALF = 2, // From orig or 3/4 to 1/2.
	UP_THREEFOUR = -1, // From 1/2 to 3/4.
	UP_ORIG = -2, // From 1/2 or 3/4 to orig.
	} RESIZE_ACTION;

	typedef enum { ORIG = 0, THREE_QUARTER = 1, ONE_HALF = 2 } RESIZE_STATE;

	/!\endcond /
	/*!
	* \brief Rate Control parameters and status
	*/
	typedef struct {
	// Rate targetting variables

	/*!
	* Baseline target rate for frame before adjustment for previous under or
	* over shoot.
	*/
	int base_frame_target;
	/*!
	* Target rate for frame after adjustment for previous under or over shoot.
	*/
	int this_frame_target; // Actual frame target after rc adjustment.

	/*!
	* Target bit budget for the current GF / ARF group of frame.
	*/
	int64_t gf_group_bits;

	/*!
	* Projected size for current frame
	*/
	int projected_frame_size;

	/*!
	* Super block rate target used with some adaptive quantization strategies.
	*/
	int sb64_target_rate;

	/*!
	* Q used on last encoded frame of the given type.
	*/
	int last_q[FRAME_TYPES];

	/*!
	* Q used for last boosted (non leaf) frame (GF/KF/ARF)
	*/
	int last_boosted_qindex;

	/*!
	* Q used for last boosted (non leaf) frame
	*/
	int last_kf_qindex;

	/*!
	* Boost factor used to calculate the extra bits allocated to ARFs and GFs
	*/
	int gfu_boost;
	/*!
	* Boost factor used to calculate the extra bits allocated to the key frame
	*/
	int kf_boost;

	/*!
	* Correction factors used to adjust the q estimate for a given target rate
	* in the encode loop.
	*/
	double rate_correction_factors[RATE_FACTOR_LEVELS];

	/*!
	* Number of frames since the last ARF / GF.
	*/
	int frames_since_golden;

	/*!
	* Number of frames till the next ARF / GF is due.
	*/
	int frames_till_gf_update_due;

	/*!
	* Number of determined gf groups left
	*/
	int intervals_till_gf_calculate_due;

	/*!
	* Stores the determined gf group lengths for a set of gf groups
	*/
	int gf_intervals[MAX_NUM_GF_INTERVALS];

	/*!
	* The current group's index into gf_intervals[]
	*/
	int cur_gf_index;

	/!\cond /
	int min_gf_interval;
	int max_gf_interval;
	int static_scene_max_gf_interval;
	int baseline_gf_interval;
	int constrained_gf_group;
	/!\endcond /
	/*!
	* Frames before the next key frame
	*/
	int frames_to_key;
	/!\cond /
	int frames_since_key;
	int this_key_frame_forced;
	int next_key_frame_forced;
	int is_src_frame_alt_ref;
	int sframe_due;

	int high_source_sad;
	uint64_t avg_source_sad;

	int avg_frame_bandwidth; // Average frame size target for clip
	int min_frame_bandwidth; // Minimum allocation used for any frame
	int max_frame_bandwidth; // Maximum burst rate allowed for a frame.
	int prev_avg_frame_bandwidth;

	int ni_av_qi;
	int ni_tot_qi;
	int ni_frames;
	int avg_frame_qindex[FRAME_TYPES];
	double tot_q;
	double avg_q;

	int64_t buffer_level;
	int64_t bits_off_target;
	int64_t vbr_bits_off_target;
	int64_t vbr_bits_off_target_fast;

	int decimation_factor;
	int decimation_count;

	int rolling_target_bits;
	int rolling_actual_bits;

	int long_rolling_target_bits;
	int long_rolling_actual_bits;

	int rate_error_estimate;

	int64_t total_actual_bits;
	int64_t total_target_bits;
	int64_t total_target_vs_actual;

	/!\endcond /
	/*!
	* User specified maximum Q allowed for current frame
	*/
	int worst_quality;
	/*!
	* User specified minimum Q allowed for current frame
	*/
	int best_quality;

	/*!
	* Initial buffuer level in ms for CBR / low delay encoding
	*/
	int64_t starting_buffer_level;
	/*!
	* Optimum / target buffuer level in ms for CBR / low delay encoding
	*/
	int64_t optimal_buffer_level;
	/*!
	* Maximum target buffuer level in ms for CBR / low delay encoding
	*/
	int64_t maximum_buffer_size;
	/!\cond /

	// rate control history for last frame(1) and the frame before(2).
	// -1: undershot
	// 1: overshoot
	// 0: not initialized.
	int rc_1_frame;
	int rc_2_frame;
	int q_1_frame;
	int q_2_frame;

	float_t arf_boost_factor;

	/!\endcond /
	/*!
	* Q index used for frame(s) at pyramid level 1, such as an ALTREF frame.
	*/
	int level1_qp;
	/*!
	* Proposed maximum alloed Q for current frame
	*/
	int active_worst_quality;
	/*!
	* Proposed minimum allowed Q different layers in a coding pyramid
	*/
	int active_best_quality[MAX_ARF_LAYERS + 1];

	/!\cond /
	int base_layer_qp;

	// Total number of stats used only for kf_boost calculation.
	int num_stats_used_for_kf_boost;
	// Total number of stats used only for gfu_boost calculation.
	int num_stats_used_for_gfu_boost;
	// Total number of stats required by gfu_boost calculation.
	int num_stats_required_for_gfu_boost;
	int next_is_fwd_key;
	int enable_scenecut_detection;
	int use_arf_in_this_kf_group;
	// Track amount of low motion in scene
	int avg_frame_low_motion;

	// For dynamic resize, 1 pass cbr.
	RESIZE_STATE resize_state;
	int resize_avg_qp;
	int resize_buffer_underflow;
	int resize_count;
	/!\endcond /
	} RATE_CONTROL;

	/!\cond /

	struct AV1_COMP;
	struct AV1EncoderConfig;

	void av1_rc_init(const struct AV1EncoderConfig *oxcf, int pass,
	RATE_CONTROL *rc);

	int av1_estimate_bits_at_q(FRAME_TYPE frame_kind, int q, int mbs,
	double correction_factor, aom_bit_depth_t bit_depth,
	const int is_screen_content_type);

	double av1_convert_qindex_to_q(int qindex, aom_bit_depth_t bit_depth);

	void av1_rc_init_minq_luts(void);

	int av1_rc_get_default_min_gf_interval(int width, int height, double framerate);
	// Note av1_rc_get_default_max_gf_interval() requires the min_gf_interval to
	// be passed in to ensure that the max_gf_interval returned is at least as bis
	// as that.
	int av1_rc_get_default_max_gf_interval(double framerate, int min_gf_interval);

	// Generally at the high level, the following flow is expected
	// to be enforced for rate control:
	// First call per frame, one of:
	// av1_rc_get_first_pass_params()
	// av1_rc_get_second_pass_params()
	// depending on the usage to set the rate control encode parameters desired.
	//
	// Then, call encode_frame_to_data_rate() to perform the
	// actual encode. This function will in turn call encode_frame()
	// one or more times, followed by one of:
	// av1_rc_postencode_update()
	// av1_rc_postencode_update_drop_frame()
	//
	// The majority of rate control parameters are only expected
	// to be set in the av1_rc_get_..._params() functions and
	// updated during the av1_rc_postencode_update...() functions.
	// The only exceptions are av1_rc_drop_frame() and
	// av1_rc_update_rate_correction_factors() functions.

	// Functions to set parameters for encoding before the actual
	// encode_frame_to_data_rate() function.
	struct EncodeFrameParams;

	// Post encode update of the rate control parameters based
	// on bytes used
	void av1_rc_postencode_update(struct AV1_COMP *cpi, uint64_t bytes_used);
	// Post encode update of the rate control parameters for dropped frames
	void av1_rc_postencode_update_drop_frame(struct AV1_COMP *cpi);

	/!\endcond /
	/*!\brief Updates the rate correction factor linking Q to output bits
	*
	* This function updates the Q rate correction factor after an encode
	* cycle depending on whether we overshot or undershot the target rate.
	*
	* \ingroup rate_control
	* \param[in] cpi Top level encoder instance structure
	* \param[in] width Frame width
	* \param[in] height Frame height
	*
	* \return None but updates the relevant rate correction factor in cpi->rc
	*/
	void av1_rc_update_rate_correction_factors(struct AV1_COMP *cpi, int width,
	int height);
	/!\cond /

	// Decide if we should drop this frame: For 1-pass CBR.
	// Changes only the decimation count in the rate control structure
	int av1_rc_drop_frame(struct AV1_COMP *cpi);

	// Computes frame size bounds.
	void av1_rc_compute_frame_size_bounds(const struct AV1_COMP *cpi,
	int this_frame_target,
	int *frame_under_shoot_limit,
	int *frame_over_shoot_limit);

	/!\endcond /

	/*!\brief Picks q and q bounds given the rate control parameters in \c cpi->rc.
	*
	* \ingroup rate_control
	* \param[in] cpi Top level encoder structure
	* \param[in,out] rc Top level rate control structure
	* \param[in] width Coded frame width
	* \param[in] height Coded frame height
	* \param[in] gf_index Index of this frame in the golden frame group
	* \param[out] bottom_index Bottom bound for q index (best quality)
	* \param[out] top_index Top bound for q index (worst quality)
	* \return Returns selected q index to be used for encoding this frame.
	* Also, updates \c rc->level1_qp.
	*/
	int av1_rc_pick_q_and_bounds(const struct AV1_COMP cpi, RATE_CONTROL rc,
	int width, int height, int gf_index,
	int bottom_index, int top_index);

	/*!\brief Estimates q to achieve a target bits per frame
	*
	* \ingroup rate_control
	* \param[in] cpi Top level encoder instance structure
	* \param[in] target_bits_per_frame Frame rate target
	* \param[in] active_worst_quality Max Q allowed
	* \param[in] active_best_quality Min Q allowed
	* \param[in] width Frame width
	* \param[in] height Frame height
	*
	* \return Returns a q index value
	*/
	int av1_rc_regulate_q(const struct AV1_COMP *cpi, int target_bits_per_frame,
	int active_best_quality, int active_worst_quality,
	int width, int height);

	/!\cond /
	// Estimates bits per mb for a given qindex and correction factor.
	int av1_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
	double correction_factor, aom_bit_depth_t bit_depth,
	const int is_screen_content_type);

	// Clamping utilities for bitrate targets for iframes and pframes.
	int av1_rc_clamp_iframe_target_size(const struct AV1_COMP *const cpi,
	int target);
	int av1_rc_clamp_pframe_target_size(const struct AV1_COMP *const cpi,
	int target, uint8_t frame_update_type);

	// Find q_index corresponding to desired_q, within [best_qindex, worst_qindex].
	// To be precise, 'q_index' is the smallest integer, for which the corresponding
	// q >= desired_q.
	// If no such q index is found, returns 'worst_qindex'.
	int av1_find_qindex(double desired_q, aom_bit_depth_t bit_depth,
	int best_qindex, int worst_qindex);

	// Computes a q delta (in "q index" terms) to get from a starting q value
	// to a target q value
	int av1_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget,
	aom_bit_depth_t bit_depth);

	// Computes a q delta (in "q index" terms) to get from a starting q value
	// to a value that should equate to the given rate ratio.
	int av1_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type,
	int qindex, double rate_target_ratio,
	const int is_screen_content_type,
	aom_bit_depth_t bit_depth);

	int av1_frame_type_qdelta(const struct AV1_COMP *cpi, int q);

	void av1_rc_update_framerate(struct AV1_COMP *cpi, int width, int height);

	void av1_rc_set_gf_interval_range(const struct AV1_COMP *const cpi,
	RATE_CONTROL *const rc);

	void av1_set_target_rate(struct AV1_COMP *cpi, int width, int height);

	int av1_resize_one_pass_cbr(struct AV1_COMP *cpi);

	void av1_rc_set_frame_target(struct AV1_COMP *cpi, int target, int width,
	int height);

	/!\endcond /
	/*!\brief Calculates how many bits to use for a P frame in one pass vbr
	*
	* \ingroup rate_control
	* \callgraph
	* \callergraph
	*
	* \param[in] cpi Top level encoder structure
	* \param[in] frame_update_type Type of frame
	*
	* \return Returns the target number of bits for this frame.
	*/
	int av1_calc_pframe_target_size_one_pass_vbr(
	const struct AV1_COMP *const cpi, FRAME_UPDATE_TYPE frame_update_type);

	/*!\brief Calculates how many bits to use for an i frame in one pass vbr
	*
	* \ingroup rate_control
	* \callgraph
	* \callergraph
	*
	* \param[in] cpi Top level encoder structure
	*
	* \return Returns the target number of bits for this frame.
	*/
	int av1_calc_iframe_target_size_one_pass_vbr(const struct AV1_COMP *const cpi);

	/*!\brief Calculates how many bits to use for a P frame in one pass cbr
	*
	* \ingroup rate_control
	* \callgraph
	* \callergraph
	*
	* \param[in] cpi Top level encoder structure
	* \param[in] frame_update_type Type of frame
	*
	* \return Returns the target number of bits for this frame.
	*/
	int av1_calc_pframe_target_size_one_pass_cbr(
	const struct AV1_COMP *cpi, FRAME_UPDATE_TYPE frame_update_type);

	/*!\brief Calculates how many bits to use for an i frame in one pass cbr
	*
	* \ingroup rate_control
	* \callgraph
	* \callergraph
	*
	* \param[in] cpi Top level encoder structure
	*
	* \return Returns the target number of bits for this frame.
	*/
	int av1_calc_iframe_target_size_one_pass_cbr(const struct AV1_COMP *cpi);

	#ifdef __cplusplus
	} // extern "C"
	#endif

	#endif // AOM_AV1_ENCODER_RATECTRL_H_