835 lines
27 KiB
C
835 lines
27 KiB
C
/*
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* Copyright (c) 2016, Alliance for Open Media. All rights reserved
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*
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* This source code is subject to the terms of the BSD 2 Clause License and
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* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
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* was not distributed with this source code in the LICENSE file, you can
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* obtain it at www.aomedia.org/license/software. If the Alliance for Open
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* Media Patent License 1.0 was not distributed with this source code in the
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* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
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*/
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#include <memory.h>
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#include <math.h>
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#include <time.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <assert.h>
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#include "aom_dsp/flow_estimation/ransac.h"
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#include "aom_dsp/mathutils.h"
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// TODO(rachelbarker): Remove dependence on code in av1/encoder/
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#include "av1/encoder/random.h"
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#define MAX_MINPTS 4
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#define MAX_DEGENERATE_ITER 10
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#define MINPTS_MULTIPLIER 5
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#define INLIER_THRESHOLD 1.25
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#define MIN_TRIALS 20
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////////////////////////////////////////////////////////////////////////////////
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// ransac
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typedef int (*IsDegenerateFunc)(double *p);
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typedef void (*NormalizeFunc)(double *p, int np, double *T);
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typedef void (*DenormalizeFunc)(double *params, double *T1, double *T2);
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typedef int (*FindTransformationFunc)(int points, double *points1,
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double *points2, double *params);
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typedef void (*ProjectPointsDoubleFunc)(double *mat, double *points,
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double *proj, int n, int stride_points,
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int stride_proj);
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static void project_points_double_translation(double *mat, double *points,
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double *proj, int n,
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int stride_points,
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int stride_proj) {
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int i;
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for (i = 0; i < n; ++i) {
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const double x = *(points++), y = *(points++);
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*(proj++) = x + mat[0];
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*(proj++) = y + mat[1];
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points += stride_points - 2;
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proj += stride_proj - 2;
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}
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}
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static void project_points_double_rotzoom(double *mat, double *points,
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double *proj, int n,
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int stride_points, int stride_proj) {
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int i;
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for (i = 0; i < n; ++i) {
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const double x = *(points++), y = *(points++);
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*(proj++) = mat[2] * x + mat[3] * y + mat[0];
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*(proj++) = -mat[3] * x + mat[2] * y + mat[1];
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points += stride_points - 2;
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proj += stride_proj - 2;
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}
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}
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static void project_points_double_affine(double *mat, double *points,
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double *proj, int n, int stride_points,
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int stride_proj) {
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int i;
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for (i = 0; i < n; ++i) {
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const double x = *(points++), y = *(points++);
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*(proj++) = mat[2] * x + mat[3] * y + mat[0];
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*(proj++) = mat[4] * x + mat[5] * y + mat[1];
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points += stride_points - 2;
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proj += stride_proj - 2;
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}
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}
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static void normalize_homography(double *pts, int n, double *T) {
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double *p = pts;
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double mean[2] = { 0, 0 };
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double msqe = 0;
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double scale;
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int i;
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assert(n > 0);
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for (i = 0; i < n; ++i, p += 2) {
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mean[0] += p[0];
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mean[1] += p[1];
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}
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mean[0] /= n;
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mean[1] /= n;
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for (p = pts, i = 0; i < n; ++i, p += 2) {
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p[0] -= mean[0];
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p[1] -= mean[1];
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msqe += sqrt(p[0] * p[0] + p[1] * p[1]);
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}
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msqe /= n;
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scale = (msqe == 0 ? 1.0 : sqrt(2) / msqe);
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T[0] = scale;
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T[1] = 0;
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T[2] = -scale * mean[0];
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T[3] = 0;
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T[4] = scale;
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T[5] = -scale * mean[1];
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T[6] = 0;
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T[7] = 0;
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T[8] = 1;
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for (p = pts, i = 0; i < n; ++i, p += 2) {
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p[0] *= scale;
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p[1] *= scale;
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}
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}
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static void invnormalize_mat(double *T, double *iT) {
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double is = 1.0 / T[0];
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double m0 = -T[2] * is;
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double m1 = -T[5] * is;
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iT[0] = is;
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iT[1] = 0;
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iT[2] = m0;
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iT[3] = 0;
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iT[4] = is;
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iT[5] = m1;
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iT[6] = 0;
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iT[7] = 0;
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iT[8] = 1;
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}
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static void denormalize_homography(double *params, double *T1, double *T2) {
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double iT2[9];
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double params2[9];
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invnormalize_mat(T2, iT2);
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multiply_mat(params, T1, params2, 3, 3, 3);
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multiply_mat(iT2, params2, params, 3, 3, 3);
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}
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static void denormalize_affine_reorder(double *params, double *T1, double *T2) {
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double params_denorm[MAX_PARAMDIM];
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params_denorm[0] = params[0];
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params_denorm[1] = params[1];
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params_denorm[2] = params[4];
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params_denorm[3] = params[2];
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params_denorm[4] = params[3];
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params_denorm[5] = params[5];
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params_denorm[6] = params_denorm[7] = 0;
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params_denorm[8] = 1;
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denormalize_homography(params_denorm, T1, T2);
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params[0] = params_denorm[2];
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params[1] = params_denorm[5];
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params[2] = params_denorm[0];
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params[3] = params_denorm[1];
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params[4] = params_denorm[3];
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params[5] = params_denorm[4];
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params[6] = params[7] = 0;
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}
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static void denormalize_rotzoom_reorder(double *params, double *T1,
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double *T2) {
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double params_denorm[MAX_PARAMDIM];
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params_denorm[0] = params[0];
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params_denorm[1] = params[1];
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params_denorm[2] = params[2];
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params_denorm[3] = -params[1];
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params_denorm[4] = params[0];
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params_denorm[5] = params[3];
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params_denorm[6] = params_denorm[7] = 0;
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params_denorm[8] = 1;
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denormalize_homography(params_denorm, T1, T2);
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params[0] = params_denorm[2];
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params[1] = params_denorm[5];
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params[2] = params_denorm[0];
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params[3] = params_denorm[1];
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params[4] = -params[3];
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params[5] = params[2];
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params[6] = params[7] = 0;
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}
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static void denormalize_translation_reorder(double *params, double *T1,
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double *T2) {
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double params_denorm[MAX_PARAMDIM];
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params_denorm[0] = 1;
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params_denorm[1] = 0;
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params_denorm[2] = params[0];
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params_denorm[3] = 0;
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params_denorm[4] = 1;
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params_denorm[5] = params[1];
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params_denorm[6] = params_denorm[7] = 0;
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params_denorm[8] = 1;
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denormalize_homography(params_denorm, T1, T2);
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params[0] = params_denorm[2];
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params[1] = params_denorm[5];
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params[2] = params[5] = 1;
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params[3] = params[4] = 0;
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params[6] = params[7] = 0;
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}
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static int find_translation(int np, double *pts1, double *pts2, double *mat) {
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int i;
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double sx, sy, dx, dy;
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double sumx, sumy;
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double T1[9], T2[9];
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normalize_homography(pts1, np, T1);
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normalize_homography(pts2, np, T2);
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sumx = 0;
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sumy = 0;
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for (i = 0; i < np; ++i) {
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dx = *(pts2++);
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dy = *(pts2++);
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sx = *(pts1++);
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sy = *(pts1++);
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sumx += dx - sx;
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sumy += dy - sy;
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}
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mat[0] = sumx / np;
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mat[1] = sumy / np;
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denormalize_translation_reorder(mat, T1, T2);
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return 0;
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}
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static int find_rotzoom(int np, double *pts1, double *pts2, double *mat) {
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const int np2 = np * 2;
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double *a = (double *)aom_malloc(sizeof(*a) * (np2 * 5 + 20));
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if (a == NULL) return 1;
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double *b = a + np2 * 4;
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double *temp = b + np2;
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int i;
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double sx, sy, dx, dy;
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double T1[9], T2[9];
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normalize_homography(pts1, np, T1);
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normalize_homography(pts2, np, T2);
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for (i = 0; i < np; ++i) {
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dx = *(pts2++);
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dy = *(pts2++);
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sx = *(pts1++);
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sy = *(pts1++);
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a[i * 2 * 4 + 0] = sx;
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a[i * 2 * 4 + 1] = sy;
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a[i * 2 * 4 + 2] = 1;
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a[i * 2 * 4 + 3] = 0;
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a[(i * 2 + 1) * 4 + 0] = sy;
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a[(i * 2 + 1) * 4 + 1] = -sx;
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a[(i * 2 + 1) * 4 + 2] = 0;
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a[(i * 2 + 1) * 4 + 3] = 1;
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b[2 * i] = dx;
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b[2 * i + 1] = dy;
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}
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if (!least_squares(4, a, np2, 4, b, temp, mat)) {
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aom_free(a);
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return 1;
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}
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denormalize_rotzoom_reorder(mat, T1, T2);
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aom_free(a);
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return 0;
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}
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static int find_affine(int np, double *pts1, double *pts2, double *mat) {
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assert(np > 0);
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const int np2 = np * 2;
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double *a = (double *)aom_malloc(sizeof(*a) * (np2 * 7 + 42));
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if (a == NULL) return 1;
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double *b = a + np2 * 6;
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double *temp = b + np2;
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int i;
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double sx, sy, dx, dy;
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double T1[9], T2[9];
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normalize_homography(pts1, np, T1);
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normalize_homography(pts2, np, T2);
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for (i = 0; i < np; ++i) {
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dx = *(pts2++);
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dy = *(pts2++);
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sx = *(pts1++);
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sy = *(pts1++);
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a[i * 2 * 6 + 0] = sx;
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a[i * 2 * 6 + 1] = sy;
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a[i * 2 * 6 + 2] = 0;
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a[i * 2 * 6 + 3] = 0;
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a[i * 2 * 6 + 4] = 1;
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a[i * 2 * 6 + 5] = 0;
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a[(i * 2 + 1) * 6 + 0] = 0;
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a[(i * 2 + 1) * 6 + 1] = 0;
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a[(i * 2 + 1) * 6 + 2] = sx;
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a[(i * 2 + 1) * 6 + 3] = sy;
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a[(i * 2 + 1) * 6 + 4] = 0;
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a[(i * 2 + 1) * 6 + 5] = 1;
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b[2 * i] = dx;
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b[2 * i + 1] = dy;
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}
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if (!least_squares(6, a, np2, 6, b, temp, mat)) {
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aom_free(a);
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return 1;
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}
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denormalize_affine_reorder(mat, T1, T2);
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aom_free(a);
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return 0;
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}
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static int get_rand_indices(int npoints, int minpts, int *indices,
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unsigned int *seed) {
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int i, j;
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int ptr = lcg_rand16(seed) % npoints;
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if (minpts > npoints) return 0;
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indices[0] = ptr;
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ptr = (ptr == npoints - 1 ? 0 : ptr + 1);
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i = 1;
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while (i < minpts) {
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int index = lcg_rand16(seed) % npoints;
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while (index) {
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ptr = (ptr == npoints - 1 ? 0 : ptr + 1);
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for (j = 0; j < i; ++j) {
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if (indices[j] == ptr) break;
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}
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if (j == i) index--;
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}
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indices[i++] = ptr;
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}
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return 1;
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}
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typedef struct {
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int num_inliers;
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double variance;
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int *inlier_indices;
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} RANSAC_MOTION;
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// Return -1 if 'a' is a better motion, 1 if 'b' is better, 0 otherwise.
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static int compare_motions(const void *arg_a, const void *arg_b) {
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const RANSAC_MOTION *motion_a = (RANSAC_MOTION *)arg_a;
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const RANSAC_MOTION *motion_b = (RANSAC_MOTION *)arg_b;
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if (motion_a->num_inliers > motion_b->num_inliers) return -1;
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if (motion_a->num_inliers < motion_b->num_inliers) return 1;
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if (motion_a->variance < motion_b->variance) return -1;
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if (motion_a->variance > motion_b->variance) return 1;
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return 0;
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}
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static int is_better_motion(const RANSAC_MOTION *motion_a,
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const RANSAC_MOTION *motion_b) {
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return compare_motions(motion_a, motion_b) < 0;
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}
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static void copy_points_at_indices(double *dest, const double *src,
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const int *indices, int num_points) {
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for (int i = 0; i < num_points; ++i) {
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const int index = indices[i];
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dest[i * 2] = src[index * 2];
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dest[i * 2 + 1] = src[index * 2 + 1];
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}
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}
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static const double kInfiniteVariance = 1e12;
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static void clear_motion(RANSAC_MOTION *motion, int num_points) {
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motion->num_inliers = 0;
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motion->variance = kInfiniteVariance;
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memset(motion->inlier_indices, 0,
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sizeof(*motion->inlier_indices) * num_points);
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}
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static int ransac(const int *matched_points, int npoints,
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int *num_inliers_by_motion, MotionModel *params_by_motion,
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int num_desired_motions, int minpts,
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IsDegenerateFunc is_degenerate,
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FindTransformationFunc find_transformation,
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ProjectPointsDoubleFunc projectpoints) {
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int trial_count = 0;
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int i = 0;
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int ret_val = 0;
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unsigned int seed = (unsigned int)npoints;
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int indices[MAX_MINPTS] = { 0 };
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double *points1, *points2;
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double *corners1, *corners2;
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double *image1_coord;
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// Store information for the num_desired_motions best transformations found
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// and the worst motion among them, as well as the motion currently under
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// consideration.
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RANSAC_MOTION *motions, *worst_kept_motion = NULL;
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RANSAC_MOTION current_motion;
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// Store the parameters and the indices of the inlier points for the motion
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// currently under consideration.
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double params_this_motion[MAX_PARAMDIM];
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double *cnp1, *cnp2;
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for (i = 0; i < num_desired_motions; ++i) {
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num_inliers_by_motion[i] = 0;
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}
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if (npoints < minpts * MINPTS_MULTIPLIER || npoints == 0) {
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return 1;
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}
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points1 = (double *)aom_malloc(sizeof(*points1) * npoints * 2);
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points2 = (double *)aom_malloc(sizeof(*points2) * npoints * 2);
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corners1 = (double *)aom_malloc(sizeof(*corners1) * npoints * 2);
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corners2 = (double *)aom_malloc(sizeof(*corners2) * npoints * 2);
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image1_coord = (double *)aom_malloc(sizeof(*image1_coord) * npoints * 2);
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motions =
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(RANSAC_MOTION *)aom_calloc(num_desired_motions, sizeof(RANSAC_MOTION));
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current_motion.inlier_indices =
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(int *)aom_malloc(sizeof(*current_motion.inlier_indices) * npoints);
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if (!(points1 && points2 && corners1 && corners2 && image1_coord && motions &&
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current_motion.inlier_indices)) {
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ret_val = 1;
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goto finish_ransac;
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}
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for (i = 0; i < num_desired_motions; ++i) {
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motions[i].inlier_indices =
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(int *)aom_malloc(sizeof(*motions->inlier_indices) * npoints);
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if (!motions[i].inlier_indices) {
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ret_val = 1;
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goto finish_ransac;
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}
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clear_motion(motions + i, npoints);
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}
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clear_motion(¤t_motion, npoints);
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worst_kept_motion = motions;
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cnp1 = corners1;
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cnp2 = corners2;
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for (i = 0; i < npoints; ++i) {
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*(cnp1++) = *(matched_points++);
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*(cnp1++) = *(matched_points++);
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*(cnp2++) = *(matched_points++);
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*(cnp2++) = *(matched_points++);
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}
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while (MIN_TRIALS > trial_count) {
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double sum_distance = 0.0;
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double sum_distance_squared = 0.0;
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clear_motion(¤t_motion, npoints);
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int degenerate = 1;
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int num_degenerate_iter = 0;
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while (degenerate) {
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num_degenerate_iter++;
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if (!get_rand_indices(npoints, minpts, indices, &seed)) {
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ret_val = 1;
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goto finish_ransac;
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}
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copy_points_at_indices(points1, corners1, indices, minpts);
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copy_points_at_indices(points2, corners2, indices, minpts);
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degenerate = is_degenerate(points1);
|
|
if (num_degenerate_iter > MAX_DEGENERATE_ITER) {
|
|
ret_val = 1;
|
|
goto finish_ransac;
|
|
}
|
|
}
|
|
|
|
if (find_transformation(minpts, points1, points2, params_this_motion)) {
|
|
trial_count++;
|
|
continue;
|
|
}
|
|
|
|
projectpoints(params_this_motion, corners1, image1_coord, npoints, 2, 2);
|
|
|
|
for (i = 0; i < npoints; ++i) {
|
|
double dx = image1_coord[i * 2] - corners2[i * 2];
|
|
double dy = image1_coord[i * 2 + 1] - corners2[i * 2 + 1];
|
|
double distance = sqrt(dx * dx + dy * dy);
|
|
|
|
if (distance < INLIER_THRESHOLD) {
|
|
current_motion.inlier_indices[current_motion.num_inliers++] = i;
|
|
sum_distance += distance;
|
|
sum_distance_squared += distance * distance;
|
|
}
|
|
}
|
|
|
|
if (current_motion.num_inliers >= worst_kept_motion->num_inliers &&
|
|
current_motion.num_inliers > 1) {
|
|
double mean_distance;
|
|
mean_distance = sum_distance / ((double)current_motion.num_inliers);
|
|
current_motion.variance =
|
|
sum_distance_squared / ((double)current_motion.num_inliers - 1.0) -
|
|
mean_distance * mean_distance * ((double)current_motion.num_inliers) /
|
|
((double)current_motion.num_inliers - 1.0);
|
|
if (is_better_motion(¤t_motion, worst_kept_motion)) {
|
|
// This motion is better than the worst currently kept motion. Remember
|
|
// the inlier points and variance. The parameters for each kept motion
|
|
// will be recomputed later using only the inliers.
|
|
worst_kept_motion->num_inliers = current_motion.num_inliers;
|
|
worst_kept_motion->variance = current_motion.variance;
|
|
memcpy(worst_kept_motion->inlier_indices, current_motion.inlier_indices,
|
|
sizeof(*current_motion.inlier_indices) * npoints);
|
|
assert(npoints > 0);
|
|
// Determine the new worst kept motion and its num_inliers and variance.
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
if (is_better_motion(worst_kept_motion, &motions[i])) {
|
|
worst_kept_motion = &motions[i];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
trial_count++;
|
|
}
|
|
|
|
// Sort the motions, best first.
|
|
qsort(motions, num_desired_motions, sizeof(RANSAC_MOTION), compare_motions);
|
|
|
|
// Recompute the motions using only the inliers.
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
if (motions[i].num_inliers >= minpts) {
|
|
copy_points_at_indices(points1, corners1, motions[i].inlier_indices,
|
|
motions[i].num_inliers);
|
|
copy_points_at_indices(points2, corners2, motions[i].inlier_indices,
|
|
motions[i].num_inliers);
|
|
|
|
find_transformation(motions[i].num_inliers, points1, points2,
|
|
params_by_motion[i].params);
|
|
|
|
params_by_motion[i].num_inliers = motions[i].num_inliers;
|
|
memcpy(params_by_motion[i].inliers, motions[i].inlier_indices,
|
|
sizeof(*motions[i].inlier_indices) * npoints);
|
|
num_inliers_by_motion[i] = motions[i].num_inliers;
|
|
}
|
|
}
|
|
|
|
finish_ransac:
|
|
aom_free(points1);
|
|
aom_free(points2);
|
|
aom_free(corners1);
|
|
aom_free(corners2);
|
|
aom_free(image1_coord);
|
|
aom_free(current_motion.inlier_indices);
|
|
if (motions) {
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
aom_free(motions[i].inlier_indices);
|
|
}
|
|
aom_free(motions);
|
|
}
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
static int ransac_double_prec(const double *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions, int minpts,
|
|
IsDegenerateFunc is_degenerate,
|
|
FindTransformationFunc find_transformation,
|
|
ProjectPointsDoubleFunc projectpoints) {
|
|
int trial_count = 0;
|
|
int i = 0;
|
|
int ret_val = 0;
|
|
|
|
unsigned int seed = (unsigned int)npoints;
|
|
|
|
int indices[MAX_MINPTS] = { 0 };
|
|
|
|
double *points1, *points2;
|
|
double *corners1, *corners2;
|
|
double *image1_coord;
|
|
|
|
// Store information for the num_desired_motions best transformations found
|
|
// and the worst motion among them, as well as the motion currently under
|
|
// consideration.
|
|
RANSAC_MOTION *motions, *worst_kept_motion = NULL;
|
|
RANSAC_MOTION current_motion;
|
|
|
|
// Store the parameters and the indices of the inlier points for the motion
|
|
// currently under consideration.
|
|
double params_this_motion[MAX_PARAMDIM];
|
|
|
|
double *cnp1, *cnp2;
|
|
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
num_inliers_by_motion[i] = 0;
|
|
}
|
|
if (npoints < minpts * MINPTS_MULTIPLIER || npoints == 0) {
|
|
return 1;
|
|
}
|
|
|
|
points1 = (double *)aom_malloc(sizeof(*points1) * npoints * 2);
|
|
points2 = (double *)aom_malloc(sizeof(*points2) * npoints * 2);
|
|
corners1 = (double *)aom_malloc(sizeof(*corners1) * npoints * 2);
|
|
corners2 = (double *)aom_malloc(sizeof(*corners2) * npoints * 2);
|
|
image1_coord = (double *)aom_malloc(sizeof(*image1_coord) * npoints * 2);
|
|
motions =
|
|
(RANSAC_MOTION *)aom_calloc(num_desired_motions, sizeof(RANSAC_MOTION));
|
|
current_motion.inlier_indices =
|
|
(int *)aom_malloc(sizeof(*current_motion.inlier_indices) * npoints);
|
|
if (!(points1 && points2 && corners1 && corners2 && image1_coord && motions &&
|
|
current_motion.inlier_indices)) {
|
|
ret_val = 1;
|
|
goto finish_ransac;
|
|
}
|
|
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
motions[i].inlier_indices =
|
|
(int *)aom_malloc(sizeof(*motions->inlier_indices) * npoints);
|
|
if (!motions[i].inlier_indices) {
|
|
ret_val = 1;
|
|
goto finish_ransac;
|
|
}
|
|
clear_motion(motions + i, npoints);
|
|
}
|
|
clear_motion(¤t_motion, npoints);
|
|
|
|
worst_kept_motion = motions;
|
|
|
|
cnp1 = corners1;
|
|
cnp2 = corners2;
|
|
for (i = 0; i < npoints; ++i) {
|
|
*(cnp1++) = *(matched_points++);
|
|
*(cnp1++) = *(matched_points++);
|
|
*(cnp2++) = *(matched_points++);
|
|
*(cnp2++) = *(matched_points++);
|
|
}
|
|
|
|
while (MIN_TRIALS > trial_count) {
|
|
double sum_distance = 0.0;
|
|
double sum_distance_squared = 0.0;
|
|
|
|
clear_motion(¤t_motion, npoints);
|
|
|
|
int degenerate = 1;
|
|
int num_degenerate_iter = 0;
|
|
|
|
while (degenerate) {
|
|
num_degenerate_iter++;
|
|
if (!get_rand_indices(npoints, minpts, indices, &seed)) {
|
|
ret_val = 1;
|
|
goto finish_ransac;
|
|
}
|
|
|
|
copy_points_at_indices(points1, corners1, indices, minpts);
|
|
copy_points_at_indices(points2, corners2, indices, minpts);
|
|
|
|
degenerate = is_degenerate(points1);
|
|
if (num_degenerate_iter > MAX_DEGENERATE_ITER) {
|
|
ret_val = 1;
|
|
goto finish_ransac;
|
|
}
|
|
}
|
|
|
|
if (find_transformation(minpts, points1, points2, params_this_motion)) {
|
|
trial_count++;
|
|
continue;
|
|
}
|
|
|
|
projectpoints(params_this_motion, corners1, image1_coord, npoints, 2, 2);
|
|
|
|
for (i = 0; i < npoints; ++i) {
|
|
double dx = image1_coord[i * 2] - corners2[i * 2];
|
|
double dy = image1_coord[i * 2 + 1] - corners2[i * 2 + 1];
|
|
double distance = sqrt(dx * dx + dy * dy);
|
|
|
|
if (distance < INLIER_THRESHOLD) {
|
|
current_motion.inlier_indices[current_motion.num_inliers++] = i;
|
|
sum_distance += distance;
|
|
sum_distance_squared += distance * distance;
|
|
}
|
|
}
|
|
|
|
if (current_motion.num_inliers >= worst_kept_motion->num_inliers &&
|
|
current_motion.num_inliers > 1) {
|
|
double mean_distance;
|
|
mean_distance = sum_distance / ((double)current_motion.num_inliers);
|
|
current_motion.variance =
|
|
sum_distance_squared / ((double)current_motion.num_inliers - 1.0) -
|
|
mean_distance * mean_distance * ((double)current_motion.num_inliers) /
|
|
((double)current_motion.num_inliers - 1.0);
|
|
if (is_better_motion(¤t_motion, worst_kept_motion)) {
|
|
// This motion is better than the worst currently kept motion. Remember
|
|
// the inlier points and variance. The parameters for each kept motion
|
|
// will be recomputed later using only the inliers.
|
|
worst_kept_motion->num_inliers = current_motion.num_inliers;
|
|
worst_kept_motion->variance = current_motion.variance;
|
|
memcpy(worst_kept_motion->inlier_indices, current_motion.inlier_indices,
|
|
sizeof(*current_motion.inlier_indices) * npoints);
|
|
assert(npoints > 0);
|
|
// Determine the new worst kept motion and its num_inliers and variance.
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
if (is_better_motion(worst_kept_motion, &motions[i])) {
|
|
worst_kept_motion = &motions[i];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
trial_count++;
|
|
}
|
|
|
|
// Sort the motions, best first.
|
|
qsort(motions, num_desired_motions, sizeof(RANSAC_MOTION), compare_motions);
|
|
|
|
// Recompute the motions using only the inliers.
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
if (motions[i].num_inliers >= minpts) {
|
|
copy_points_at_indices(points1, corners1, motions[i].inlier_indices,
|
|
motions[i].num_inliers);
|
|
copy_points_at_indices(points2, corners2, motions[i].inlier_indices,
|
|
motions[i].num_inliers);
|
|
|
|
find_transformation(motions[i].num_inliers, points1, points2,
|
|
params_by_motion[i].params);
|
|
memcpy(params_by_motion[i].inliers, motions[i].inlier_indices,
|
|
sizeof(*motions[i].inlier_indices) * npoints);
|
|
}
|
|
num_inliers_by_motion[i] = motions[i].num_inliers;
|
|
}
|
|
|
|
finish_ransac:
|
|
aom_free(points1);
|
|
aom_free(points2);
|
|
aom_free(corners1);
|
|
aom_free(corners2);
|
|
aom_free(image1_coord);
|
|
aom_free(current_motion.inlier_indices);
|
|
if (motions) {
|
|
for (i = 0; i < num_desired_motions; ++i) {
|
|
aom_free(motions[i].inlier_indices);
|
|
}
|
|
aom_free(motions);
|
|
}
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
static int is_collinear3(double *p1, double *p2, double *p3) {
|
|
static const double collinear_eps = 1e-3;
|
|
const double v =
|
|
(p2[0] - p1[0]) * (p3[1] - p1[1]) - (p2[1] - p1[1]) * (p3[0] - p1[0]);
|
|
return fabs(v) < collinear_eps;
|
|
}
|
|
|
|
static int is_degenerate_translation(double *p) {
|
|
return (p[0] - p[2]) * (p[0] - p[2]) + (p[1] - p[3]) * (p[1] - p[3]) <= 2;
|
|
}
|
|
|
|
static int is_degenerate_affine(double *p) {
|
|
return is_collinear3(p, p + 2, p + 4);
|
|
}
|
|
|
|
static int ransac_translation(int *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3,
|
|
is_degenerate_translation, find_translation,
|
|
project_points_double_translation);
|
|
}
|
|
|
|
static int ransac_rotzoom(int *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3, is_degenerate_affine,
|
|
find_rotzoom, project_points_double_rotzoom);
|
|
}
|
|
|
|
static int ransac_affine(int *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3, is_degenerate_affine,
|
|
find_affine, project_points_double_affine);
|
|
}
|
|
|
|
RansacFunc av1_get_ransac_type(TransformationType type) {
|
|
switch (type) {
|
|
case AFFINE: return ransac_affine;
|
|
case ROTZOOM: return ransac_rotzoom;
|
|
case TRANSLATION: return ransac_translation;
|
|
default: assert(0); return NULL;
|
|
}
|
|
}
|
|
|
|
static int ransac_translation_double_prec(double *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac_double_prec(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3,
|
|
is_degenerate_translation, find_translation,
|
|
project_points_double_translation);
|
|
}
|
|
|
|
static int ransac_rotzoom_double_prec(double *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac_double_prec(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3,
|
|
is_degenerate_affine, find_rotzoom,
|
|
project_points_double_rotzoom);
|
|
}
|
|
|
|
static int ransac_affine_double_prec(double *matched_points, int npoints,
|
|
int *num_inliers_by_motion,
|
|
MotionModel *params_by_motion,
|
|
int num_desired_motions) {
|
|
return ransac_double_prec(matched_points, npoints, num_inliers_by_motion,
|
|
params_by_motion, num_desired_motions, 3,
|
|
is_degenerate_affine, find_affine,
|
|
project_points_double_affine);
|
|
}
|
|
|
|
RansacFuncDouble av1_get_ransac_double_prec_type(TransformationType type) {
|
|
switch (type) {
|
|
case AFFINE: return ransac_affine_double_prec;
|
|
case ROTZOOM: return ransac_rotzoom_double_prec;
|
|
case TRANSLATION: return ransac_translation_double_prec;
|
|
default: assert(0); return NULL;
|
|
}
|
|
}
|