text: // clang-format off
  /*
   * Copyright (c) 2016, Alliance for Open Media. All rights reserved
   *
   * This source code is subject to the terms of the BSD 2 Clause License and
   * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
   * was not distributed with this source code in the LICENSE file, you can
   * obtain it at www.aomedia.org/license/software. 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 www.aomedia.org/license/patent.
   */
  
  #ifndef AOM_AV1_ENCODER_GLOBAL_MOTION_H_
  #define AOM_AV1_ENCODER_GLOBAL_MOTION_H_
  
  #include "EbDefinitions.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #if defined(__clang__) && defined(__has_warning)
  #if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
  #define AOM_FALLTHROUGH_INTENDED [[clang::fallthrough]]  // NOLINT
  #endif
  #elif defined(__GNUC__) && __GNUC__ >= 7
  #define AOM_FALLTHROUGH_INTENDED __attribute__((fallthrough))  // NOLINT
  #endif
  
  #ifndef AOM_FALLTHROUGH_INTENDED
  #define AOM_FALLTHROUGH_INTENDED \
    do {                           \
    } while (0)
  #endif
  
  #define MAX_CORNERS 4096
  #define RANSAC_NUM_MOTIONS 1
  
  typedef enum {
    GLOBAL_MOTION_FEATURE_BASED,
  } GlobalMotionEstimationType;
  
  enum {
    GM_ERRORADV_TR_0,
    GM_ERRORADV_TR_1,
    GM_ERRORADV_TR_2,
    GM_ERRORADV_TR_TYPES,
  } UENUM1BYTE(GM_ERRORADV_TYPE);
  
  #define MAX_PARAMDIM 9
  
  typedef struct {
    double params[MAX_PARAMDIM - 1];
    int *inliers;
    int num_inliers;
  } MotionModel;
  
  void av1_convert_model_to_params(const double *params,
                                   EbWarpedMotionParams *model);
  
  int av1_is_enough_erroradvantage(double best_erroradvantage, int params_cost,
                                   int erroradv_type);
  
  // Returns the av1_warp_error between "dst" and the result of applying the
  // motion params that result from fine-tuning "wm" to "ref". Note that "wm" is
  // modified in place.
  int64_t av1_refine_integerized_param(EbWarpedMotionParams *wm, TransformationType wmtype, int use_hbd, int bd,
      uint8_t *ref, int r_width, int r_height, int r_stride, uint8_t *dst,
      int d_width, int d_height, int d_stride, int n_refinements,
      int64_t best_frame_error);
  
  /*
    Computes "num_motions" candidate global motion parameters between two frames.
    The array "params_by_motion" should be length 8 * "num_motions". The ordering
    of each set of parameters is best described  by the homography:
  
          [x'     (m2 m3 m0   [x
      z .  y'  =   m4 m5 m1 *  y
           1]      m6 m7 1)    1]
  
    where m{i} represents the ith value in any given set of parameters.
  
    "num_inliers" should be length "num_motions", and will be populated with the
    number of inlier feature points for each motion. Params for which the
    num_inliers entry is 0 should be ignored by the caller.
  */
  int av1_compute_global_motion(TransformationType type,
                                unsigned char *frm_buffer, int frm_width,
                                int frm_height, int frm_stride, int *frm_corners,
                                int num_frm_corners, uint8_t *ref, int ref_stride,
                                int bit_depth,
                                GlobalMotionEstimationType gm_estimation_type,
                                int *num_inliers_by_motion,
                                MotionModel *params_by_motion, int num_motions);
  #ifdef __cplusplus
  }  // extern "C"
  #endif
  #endif  // AOM_AV1_ENCODER_GLOBAL_MOTION_H_
  // clang-format on
  