Move warping model estimation functions to COMMON folder

These functions will be called by both enc and dec in WARPED_MOTION
experiment.

Change-Id: I4b4a20af111b30822760aee8c9451e9ccbb2dd05
diff --git a/av1/common/warped_motion.c b/av1/common/warped_motion.c
index 167cb66..fc632c3 100644
--- a/av1/common/warped_motion.c
+++ b/av1/common/warped_motion.c
@@ -632,3 +632,587 @@
     default: assert(0 && "Invalid TransformationType");
   }
 }
+
+///////////////////////////////////////////////////////////////////////////////
+// svdcmp
+// Adopted from Numerical Recipes in C
+
+static const double TINY_NEAR_ZERO = 1.0E-12;
+
+static INLINE double sign(double a, double b) {
+  return ((b) >= 0 ? fabs(a) : -fabs(a));
+}
+
+static INLINE double pythag(double a, double b) {
+  double ct;
+  const double absa = fabs(a);
+  const double absb = fabs(b);
+
+  if (absa > absb) {
+    ct = absb / absa;
+    return absa * sqrt(1.0 + ct * ct);
+  } else {
+    ct = absa / absb;
+    return (absb == 0) ? 0 : absb * sqrt(1.0 + ct * ct);
+  }
+}
+
+static void multiply_mat(const double *m1, const double *m2, double *res,
+                         const int m1_rows, const int inner_dim,
+                         const int m2_cols) {
+  double sum;
+
+  int row, col, inner;
+  for (row = 0; row < m1_rows; ++row) {
+    for (col = 0; col < m2_cols; ++col) {
+      sum = 0;
+      for (inner = 0; inner < inner_dim; ++inner)
+        sum += m1[row * inner_dim + inner] * m2[inner * m2_cols + col];
+      *(res++) = sum;
+    }
+  }
+}
+
+static int svdcmp(double **u, int m, int n, double w[], double **v) {
+  const int max_its = 30;
+  int flag, i, its, j, jj, k, l, nm;
+  double anorm, c, f, g, h, s, scale, x, y, z;
+  double *rv1 = (double *)aom_malloc(sizeof(*rv1) * (n + 1));
+  g = scale = anorm = 0.0;
+  for (i = 0; i < n; i++) {
+    l = i + 1;
+    rv1[i] = scale * g;
+    g = s = scale = 0.0;
+    if (i < m) {
+      for (k = i; k < m; k++) scale += fabs(u[k][i]);
+      if (scale) {
+        for (k = i; k < m; k++) {
+          u[k][i] /= scale;
+          s += u[k][i] * u[k][i];
+        }
+        f = u[i][i];
+        g = -sign(sqrt(s), f);
+        h = f * g - s;
+        u[i][i] = f - g;
+        for (j = l; j < n; j++) {
+          for (s = 0.0, k = i; k < m; k++) s += u[k][i] * u[k][j];
+          f = s / h;
+          for (k = i; k < m; k++) u[k][j] += f * u[k][i];
+        }
+        for (k = i; k < m; k++) u[k][i] *= scale;
+      }
+    }
+    w[i] = scale * g;
+    g = s = scale = 0.0;
+    if (i < m && i != n - 1) {
+      for (k = l; k < n; k++) scale += fabs(u[i][k]);
+      if (scale) {
+        for (k = l; k < n; k++) {
+          u[i][k] /= scale;
+          s += u[i][k] * u[i][k];
+        }
+        f = u[i][l];
+        g = -sign(sqrt(s), f);
+        h = f * g - s;
+        u[i][l] = f - g;
+        for (k = l; k < n; k++) rv1[k] = u[i][k] / h;
+        for (j = l; j < m; j++) {
+          for (s = 0.0, k = l; k < n; k++) s += u[j][k] * u[i][k];
+          for (k = l; k < n; k++) u[j][k] += s * rv1[k];
+        }
+        for (k = l; k < n; k++) u[i][k] *= scale;
+      }
+    }
+    anorm = fmax(anorm, (fabs(w[i]) + fabs(rv1[i])));
+  }
+
+  for (i = n - 1; i >= 0; i--) {
+    if (i < n - 1) {
+      if (g) {
+        for (j = l; j < n; j++) v[j][i] = (u[i][j] / u[i][l]) / g;
+        for (j = l; j < n; j++) {
+          for (s = 0.0, k = l; k < n; k++) s += u[i][k] * v[k][j];
+          for (k = l; k < n; k++) v[k][j] += s * v[k][i];
+        }
+      }
+      for (j = l; j < n; j++) v[i][j] = v[j][i] = 0.0;
+    }
+    v[i][i] = 1.0;
+    g = rv1[i];
+    l = i;
+  }
+  for (i = AOMMIN(m, n) - 1; i >= 0; i--) {
+    l = i + 1;
+    g = w[i];
+    for (j = l; j < n; j++) u[i][j] = 0.0;
+    if (g) {
+      g = 1.0 / g;
+      for (j = l; j < n; j++) {
+        for (s = 0.0, k = l; k < m; k++) s += u[k][i] * u[k][j];
+        f = (s / u[i][i]) * g;
+        for (k = i; k < m; k++) u[k][j] += f * u[k][i];
+      }
+      for (j = i; j < m; j++) u[j][i] *= g;
+    } else {
+      for (j = i; j < m; j++) u[j][i] = 0.0;
+    }
+    ++u[i][i];
+  }
+  for (k = n - 1; k >= 0; k--) {
+    for (its = 0; its < max_its; its++) {
+      flag = 1;
+      for (l = k; l >= 0; l--) {
+        nm = l - 1;
+        if ((double)(fabs(rv1[l]) + anorm) == anorm || nm < 0) {
+          flag = 0;
+          break;
+        }
+        if ((double)(fabs(w[nm]) + anorm) == anorm) break;
+      }
+      if (flag) {
+        c = 0.0;
+        s = 1.0;
+        for (i = l; i <= k; i++) {
+          f = s * rv1[i];
+          rv1[i] = c * rv1[i];
+          if ((double)(fabs(f) + anorm) == anorm) break;
+          g = w[i];
+          h = pythag(f, g);
+          w[i] = h;
+          h = 1.0 / h;
+          c = g * h;
+          s = -f * h;
+          for (j = 0; j < m; j++) {
+            y = u[j][nm];
+            z = u[j][i];
+            u[j][nm] = y * c + z * s;
+            u[j][i] = z * c - y * s;
+          }
+        }
+      }
+      z = w[k];
+      if (l == k) {
+        if (z < 0.0) {
+          w[k] = -z;
+          for (j = 0; j < n; j++) v[j][k] = -v[j][k];
+        }
+        break;
+      }
+      if (its == max_its - 1) {
+        return 1;
+      }
+      assert(k > 0);
+      x = w[l];
+      nm = k - 1;
+      y = w[nm];
+      g = rv1[nm];
+      h = rv1[k];
+      f = ((y - z) * (y + z) + (g - h) * (g + h)) / (2.0 * h * y);
+      g = pythag(f, 1.0);
+      f = ((x - z) * (x + z) + h * ((y / (f + sign(g, f))) - h)) / x;
+      c = s = 1.0;
+      for (j = l; j <= nm; j++) {
+        i = j + 1;
+        g = rv1[i];
+        y = w[i];
+        h = s * g;
+        g = c * g;
+        z = pythag(f, h);
+        rv1[j] = z;
+        c = f / z;
+        s = h / z;
+        f = x * c + g * s;
+        g = g * c - x * s;
+        h = y * s;
+        y *= c;
+        for (jj = 0; jj < n; jj++) {
+          x = v[jj][j];
+          z = v[jj][i];
+          v[jj][j] = x * c + z * s;
+          v[jj][i] = z * c - x * s;
+        }
+        z = pythag(f, h);
+        w[j] = z;
+        if (z) {
+          z = 1.0 / z;
+          c = f * z;
+          s = h * z;
+        }
+        f = c * g + s * y;
+        x = c * y - s * g;
+        for (jj = 0; jj < m; jj++) {
+          y = u[jj][j];
+          z = u[jj][i];
+          u[jj][j] = y * c + z * s;
+          u[jj][i] = z * c - y * s;
+        }
+      }
+      rv1[l] = 0.0;
+      rv1[k] = f;
+      w[k] = x;
+    }
+  }
+  aom_free(rv1);
+  return 0;
+}
+
+static int SVD(double *U, double *W, double *V, double *matx, int M, int N) {
+  // Assumes allocation for U is MxN
+  double **nrU = (double **)aom_malloc((M) * sizeof(*nrU));
+  double **nrV = (double **)aom_malloc((N) * sizeof(*nrV));
+  int problem, i;
+
+  problem = !(nrU && nrV);
+  if (!problem) {
+    for (i = 0; i < M; i++) {
+      nrU[i] = &U[i * N];
+    }
+    for (i = 0; i < N; i++) {
+      nrV[i] = &V[i * N];
+    }
+  } else {
+    if (nrU) aom_free(nrU);
+    if (nrV) aom_free(nrV);
+    return 1;
+  }
+
+  /* copy from given matx into nrU */
+  for (i = 0; i < M; i++) {
+    memcpy(&(nrU[i][0]), matx + N * i, N * sizeof(*matx));
+  }
+
+  /* HERE IT IS: do SVD */
+  if (svdcmp(nrU, M, N, W, nrV)) {
+    aom_free(nrU);
+    aom_free(nrV);
+    return 1;
+  }
+
+  /* aom_free Numerical Recipes arrays */
+  aom_free(nrU);
+  aom_free(nrV);
+
+  return 0;
+}
+
+int pseudo_inverse(double *inv, double *matx, const int M, const int N) {
+  double ans;
+  int i, j, k;
+  double *const U = (double *)aom_malloc(M * N * sizeof(*matx));
+  double *const W = (double *)aom_malloc(N * sizeof(*matx));
+  double *const V = (double *)aom_malloc(N * N * sizeof(*matx));
+
+  if (!(U && W && V)) {
+    return 1;
+  }
+  if (SVD(U, W, V, matx, M, N)) {
+    return 1;
+  }
+  for (i = 0; i < N; i++) {
+    if (fabs(W[i]) < TINY_NEAR_ZERO) {
+      return 1;
+    }
+  }
+
+  for (i = 0; i < N; i++) {
+    for (j = 0; j < M; j++) {
+      ans = 0;
+      for (k = 0; k < N; k++) {
+        ans += V[k + N * i] * U[k + N * j] / W[k];
+      }
+      inv[j + M * i] = ans;
+    }
+  }
+  aom_free(U);
+  aom_free(W);
+  aom_free(V);
+  return 0;
+}
+
+static void normalize_homography(double *pts, int n, double *T) {
+  // Assume the points are 2d coordinates with scale = 1
+  double *p = pts;
+  double mean[2] = { 0, 0 };
+  double msqe = 0;
+  double scale;
+  int i;
+  for (i = 0; i < n; ++i, p += 2) {
+    mean[0] += p[0];
+    mean[1] += p[1];
+  }
+  mean[0] /= n;
+  mean[1] /= n;
+  for (p = pts, i = 0; i < n; ++i, p += 2) {
+    p[0] -= mean[0];
+    p[1] -= mean[1];
+    msqe += sqrt(p[0] * p[0] + p[1] * p[1]);
+  }
+  msqe /= n;
+  scale = sqrt(2) / msqe;
+  T[0] = scale;
+  T[1] = 0;
+  T[2] = -scale * mean[0];
+  T[3] = 0;
+  T[4] = scale;
+  T[5] = -scale * mean[1];
+  T[6] = 0;
+  T[7] = 0;
+  T[8] = 1;
+  for (p = pts, i = 0; i < n; ++i, p += 2) {
+    p[0] *= scale;
+    p[1] *= scale;
+  }
+}
+
+static void invnormalize_mat(double *T, double *iT) {
+  double is = 1.0 / T[0];
+  double m0 = -T[2] * is;
+  double m1 = -T[5] * is;
+  iT[0] = is;
+  iT[1] = 0;
+  iT[2] = m0;
+  iT[3] = 0;
+  iT[4] = is;
+  iT[5] = m1;
+  iT[6] = 0;
+  iT[7] = 0;
+  iT[8] = 1;
+}
+
+static void denormalize_homography(double *params, double *T1, double *T2) {
+  double iT2[9];
+  double params2[9];
+  invnormalize_mat(T2, iT2);
+  multiply_mat(params, T1, params2, 3, 3, 3);
+  multiply_mat(iT2, params2, params, 3, 3, 3);
+}
+
+static void denormalize_affine(double *params, double *T1, double *T2) {
+  double params_denorm[MAX_PARAMDIM];
+  params_denorm[0] = params[0];
+  params_denorm[1] = params[1];
+  params_denorm[2] = params[4];
+  params_denorm[3] = params[2];
+  params_denorm[4] = params[3];
+  params_denorm[5] = params[5];
+  params_denorm[6] = params_denorm[7] = 0;
+  params_denorm[8] = 1;
+  denormalize_homography(params_denorm, T1, T2);
+  params[0] = params_denorm[5];
+  params[1] = params_denorm[2];
+  params[2] = params_denorm[1];
+  params[3] = params_denorm[0];
+  params[4] = params_denorm[3];
+  params[5] = params_denorm[4];
+}
+
+static void denormalize_rotzoom(double *params, double *T1, double *T2) {
+  double params_denorm[MAX_PARAMDIM];
+  params_denorm[0] = params[0];
+  params_denorm[1] = params[1];
+  params_denorm[2] = params[2];
+  params_denorm[3] = -params[1];
+  params_denorm[4] = params[0];
+  params_denorm[5] = params[3];
+  params_denorm[6] = params_denorm[7] = 0;
+  params_denorm[8] = 1;
+  denormalize_homography(params_denorm, T1, T2);
+  params[0] = params_denorm[5];
+  params[1] = params_denorm[2];
+  params[2] = params_denorm[1];
+  params[3] = params_denorm[0];
+}
+
+static void denormalize_translation(double *params, double *T1, double *T2) {
+  double params_denorm[MAX_PARAMDIM];
+  params_denorm[0] = 1;
+  params_denorm[1] = 0;
+  params_denorm[2] = params[0];
+  params_denorm[3] = 0;
+  params_denorm[4] = 1;
+  params_denorm[5] = params[1];
+  params_denorm[6] = params_denorm[7] = 0;
+  params_denorm[8] = 1;
+  denormalize_homography(params_denorm, T1, T2);
+  params[0] = params_denorm[5];
+  params[1] = params_denorm[2];
+}
+
+int find_translation(const int np, double *pts1, double *pts2, double *mat) {
+  int i;
+  double sx, sy, dx, dy;
+  double sumx, sumy;
+
+  double T1[9], T2[9];
+  normalize_homography(pts1, np, T1);
+  normalize_homography(pts2, np, T2);
+
+  sumx = 0;
+  sumy = 0;
+  for (i = 0; i < np; ++i) {
+    dx = *(pts2++);
+    dy = *(pts2++);
+    sx = *(pts1++);
+    sy = *(pts1++);
+
+    sumx += dx - sx;
+    sumy += dy - sy;
+  }
+  mat[0] = sumx / np;
+  mat[1] = sumy / np;
+  denormalize_translation(mat, T1, T2);
+  return 0;
+}
+
+int find_rotzoom(const int np, double *pts1, double *pts2, double *mat) {
+  const int np2 = np * 2;
+  double *a = (double *)aom_malloc(sizeof(*a) * np2 * 9);
+  double *b = a + np2 * 4;
+  double *temp = b + np2;
+  int i;
+  double sx, sy, dx, dy;
+
+  double T1[9], T2[9];
+  normalize_homography(pts1, np, T1);
+  normalize_homography(pts2, np, T2);
+
+  for (i = 0; i < np; ++i) {
+    dx = *(pts2++);
+    dy = *(pts2++);
+    sx = *(pts1++);
+    sy = *(pts1++);
+
+    a[i * 2 * 4 + 0] = sx;
+    a[i * 2 * 4 + 1] = sy;
+    a[i * 2 * 4 + 2] = 1;
+    a[i * 2 * 4 + 3] = 0;
+    a[(i * 2 + 1) * 4 + 0] = sy;
+    a[(i * 2 + 1) * 4 + 1] = -sx;
+    a[(i * 2 + 1) * 4 + 2] = 0;
+    a[(i * 2 + 1) * 4 + 3] = 1;
+
+    b[2 * i] = dx;
+    b[2 * i + 1] = dy;
+  }
+  if (pseudo_inverse(temp, a, np2, 4)) {
+    aom_free(a);
+    return 1;
+  }
+  multiply_mat(temp, b, mat, 4, np2, 1);
+  denormalize_rotzoom(mat, T1, T2);
+  aom_free(a);
+  return 0;
+}
+
+int find_affine(const int np, double *pts1, double *pts2, double *mat) {
+  const int np2 = np * 2;
+  double *a = (double *)aom_malloc(sizeof(*a) * np2 * 13);
+  double *b = a + np2 * 6;
+  double *temp = b + np2;
+  int i;
+  double sx, sy, dx, dy;
+
+  double T1[9], T2[9];
+  normalize_homography(pts1, np, T1);
+  normalize_homography(pts2, np, T2);
+
+  for (i = 0; i < np; ++i) {
+    dx = *(pts2++);
+    dy = *(pts2++);
+    sx = *(pts1++);
+    sy = *(pts1++);
+
+    a[i * 2 * 6 + 0] = sx;
+    a[i * 2 * 6 + 1] = sy;
+    a[i * 2 * 6 + 2] = 0;
+    a[i * 2 * 6 + 3] = 0;
+    a[i * 2 * 6 + 4] = 1;
+    a[i * 2 * 6 + 5] = 0;
+    a[(i * 2 + 1) * 6 + 0] = 0;
+    a[(i * 2 + 1) * 6 + 1] = 0;
+    a[(i * 2 + 1) * 6 + 2] = sx;
+    a[(i * 2 + 1) * 6 + 3] = sy;
+    a[(i * 2 + 1) * 6 + 4] = 0;
+    a[(i * 2 + 1) * 6 + 5] = 1;
+
+    b[2 * i] = dx;
+    b[2 * i + 1] = dy;
+  }
+  if (pseudo_inverse(temp, a, np2, 6)) {
+    aom_free(a);
+    return 1;
+  }
+  multiply_mat(temp, b, mat, 6, np2, 1);
+  denormalize_affine(mat, T1, T2);
+  aom_free(a);
+  return 0;
+}
+
+int find_homography(const int np, double *pts1, double *pts2, double *mat) {
+  // Implemented from Peter Kovesi's normalized implementation
+  const int np3 = np * 3;
+  double *a = (double *)aom_malloc(sizeof(*a) * np3 * 18);
+  double *U = a + np3 * 9;
+  double S[9], V[9 * 9];
+  int i, mini;
+  double sx, sy, dx, dy;
+  double T1[9], T2[9];
+
+  normalize_homography(pts1, np, T1);
+  normalize_homography(pts2, np, T2);
+
+  for (i = 0; i < np; ++i) {
+    dx = *(pts2++);
+    dy = *(pts2++);
+    sx = *(pts1++);
+    sy = *(pts1++);
+
+    a[i * 3 * 9 + 0] = a[i * 3 * 9 + 1] = a[i * 3 * 9 + 2] = 0;
+    a[i * 3 * 9 + 3] = -sx;
+    a[i * 3 * 9 + 4] = -sy;
+    a[i * 3 * 9 + 5] = -1;
+    a[i * 3 * 9 + 6] = dy * sx;
+    a[i * 3 * 9 + 7] = dy * sy;
+    a[i * 3 * 9 + 8] = dy;
+
+    a[(i * 3 + 1) * 9 + 0] = sx;
+    a[(i * 3 + 1) * 9 + 1] = sy;
+    a[(i * 3 + 1) * 9 + 2] = 1;
+    a[(i * 3 + 1) * 9 + 3] = a[(i * 3 + 1) * 9 + 4] = a[(i * 3 + 1) * 9 + 5] =
+        0;
+    a[(i * 3 + 1) * 9 + 6] = -dx * sx;
+    a[(i * 3 + 1) * 9 + 7] = -dx * sy;
+    a[(i * 3 + 1) * 9 + 8] = -dx;
+
+    a[(i * 3 + 2) * 9 + 0] = -dy * sx;
+    a[(i * 3 + 2) * 9 + 1] = -dy * sy;
+    a[(i * 3 + 2) * 9 + 2] = -dy;
+    a[(i * 3 + 2) * 9 + 3] = dx * sx;
+    a[(i * 3 + 2) * 9 + 4] = dx * sy;
+    a[(i * 3 + 2) * 9 + 5] = dx;
+    a[(i * 3 + 2) * 9 + 6] = a[(i * 3 + 2) * 9 + 7] = a[(i * 3 + 2) * 9 + 8] =
+        0;
+  }
+
+  if (SVD(U, S, V, a, np3, 9)) {
+    aom_free(a);
+    return 1;
+  } else {
+    double minS = 1e12;
+    mini = -1;
+    for (i = 0; i < 9; ++i) {
+      if (S[i] < minS) {
+        minS = S[i];
+        mini = i;
+      }
+    }
+  }
+
+  for (i = 0; i < 9; i++) mat[i] = V[i * 9 + mini];
+  denormalize_homography(mat, T1, T2);
+  aom_free(a);
+  if (mat[8] == 0.0) {
+    return 1;
+  }
+  return 0;
+}
diff --git a/av1/common/warped_motion.h b/av1/common/warped_motion.h
index 53f06dd..da92599 100644
--- a/av1/common/warped_motion.h
+++ b/av1/common/warped_motion.h
@@ -22,6 +22,8 @@
 #include "aom_dsp/aom_dsp_common.h"
 #include "av1/common/mv.h"
 
+#define MAX_PARAMDIM 9
+
 typedef void (*ProjectPointsFunc)(int16_t *mat, int *points, int *proj,
                                   const int n, const int stride_points,
                                   const int stride_proj,
@@ -67,4 +69,9 @@
 // Integerize model into the WarpedMotionParams structure
 void av1_integerize_model(const double *model, TransformationType wmtype,
                           WarpedMotionParams *wm);
+
+int find_translation(const int np, double *pts1, double *pts2, double *mat);
+int find_rotzoom(const int np, double *pts1, double *pts2, double *mat);
+int find_affine(const int np, double *pts1, double *pts2, double *mat);
+int find_homography(const int np, double *pts1, double *pts2, double *mat);
 #endif  // AV1_COMMON_WARPED_MOTION_H_
diff --git a/av1/encoder/ransac.c b/av1/encoder/ransac.c
index 0a26396..0c8ad67 100644
--- a/av1/encoder/ransac.c
+++ b/av1/encoder/ransac.c
@@ -17,307 +17,11 @@
 
 #include "av1/encoder/ransac.h"
 
-#define MAX_PARAMDIM 9
 #define MAX_MINPTS 4
 
 #define MAX_DEGENERATE_ITER 10
 #define MINPTS_MULTIPLIER 5
 
-// svdcmp
-// Adopted from Numerical Recipes in C
-
-static const double TINY_NEAR_ZERO = 1.0E-12;
-
-static INLINE double sign(double a, double b) {
-  return ((b) >= 0 ? fabs(a) : -fabs(a));
-}
-
-static INLINE double pythag(double a, double b) {
-  double ct;
-  const double absa = fabs(a);
-  const double absb = fabs(b);
-
-  if (absa > absb) {
-    ct = absb / absa;
-    return absa * sqrt(1.0 + ct * ct);
-  } else {
-    ct = absa / absb;
-    return (absb == 0) ? 0 : absb * sqrt(1.0 + ct * ct);
-  }
-}
-
-static void multiply_mat(const double *m1, const double *m2, double *res,
-                         const int m1_rows, const int inner_dim,
-                         const int m2_cols) {
-  double sum;
-
-  int row, col, inner;
-  for (row = 0; row < m1_rows; ++row) {
-    for (col = 0; col < m2_cols; ++col) {
-      sum = 0;
-      for (inner = 0; inner < inner_dim; ++inner)
-        sum += m1[row * inner_dim + inner] * m2[inner * m2_cols + col];
-      *(res++) = sum;
-    }
-  }
-}
-
-static int svdcmp(double **u, int m, int n, double w[], double **v) {
-  const int max_its = 30;
-  int flag, i, its, j, jj, k, l, nm;
-  double anorm, c, f, g, h, s, scale, x, y, z;
-  double *rv1 = (double *)aom_malloc(sizeof(*rv1) * (n + 1));
-  g = scale = anorm = 0.0;
-  for (i = 0; i < n; i++) {
-    l = i + 1;
-    rv1[i] = scale * g;
-    g = s = scale = 0.0;
-    if (i < m) {
-      for (k = i; k < m; k++) scale += fabs(u[k][i]);
-      if (scale) {
-        for (k = i; k < m; k++) {
-          u[k][i] /= scale;
-          s += u[k][i] * u[k][i];
-        }
-        f = u[i][i];
-        g = -sign(sqrt(s), f);
-        h = f * g - s;
-        u[i][i] = f - g;
-        for (j = l; j < n; j++) {
-          for (s = 0.0, k = i; k < m; k++) s += u[k][i] * u[k][j];
-          f = s / h;
-          for (k = i; k < m; k++) u[k][j] += f * u[k][i];
-        }
-        for (k = i; k < m; k++) u[k][i] *= scale;
-      }
-    }
-    w[i] = scale * g;
-    g = s = scale = 0.0;
-    if (i < m && i != n - 1) {
-      for (k = l; k < n; k++) scale += fabs(u[i][k]);
-      if (scale) {
-        for (k = l; k < n; k++) {
-          u[i][k] /= scale;
-          s += u[i][k] * u[i][k];
-        }
-        f = u[i][l];
-        g = -sign(sqrt(s), f);
-        h = f * g - s;
-        u[i][l] = f - g;
-        for (k = l; k < n; k++) rv1[k] = u[i][k] / h;
-        for (j = l; j < m; j++) {
-          for (s = 0.0, k = l; k < n; k++) s += u[j][k] * u[i][k];
-          for (k = l; k < n; k++) u[j][k] += s * rv1[k];
-        }
-        for (k = l; k < n; k++) u[i][k] *= scale;
-      }
-    }
-    anorm = fmax(anorm, (fabs(w[i]) + fabs(rv1[i])));
-  }
-
-  for (i = n - 1; i >= 0; i--) {
-    if (i < n - 1) {
-      if (g) {
-        for (j = l; j < n; j++) v[j][i] = (u[i][j] / u[i][l]) / g;
-        for (j = l; j < n; j++) {
-          for (s = 0.0, k = l; k < n; k++) s += u[i][k] * v[k][j];
-          for (k = l; k < n; k++) v[k][j] += s * v[k][i];
-        }
-      }
-      for (j = l; j < n; j++) v[i][j] = v[j][i] = 0.0;
-    }
-    v[i][i] = 1.0;
-    g = rv1[i];
-    l = i;
-  }
-  for (i = AOMMIN(m, n) - 1; i >= 0; i--) {
-    l = i + 1;
-    g = w[i];
-    for (j = l; j < n; j++) u[i][j] = 0.0;
-    if (g) {
-      g = 1.0 / g;
-      for (j = l; j < n; j++) {
-        for (s = 0.0, k = l; k < m; k++) s += u[k][i] * u[k][j];
-        f = (s / u[i][i]) * g;
-        for (k = i; k < m; k++) u[k][j] += f * u[k][i];
-      }
-      for (j = i; j < m; j++) u[j][i] *= g;
-    } else {
-      for (j = i; j < m; j++) u[j][i] = 0.0;
-    }
-    ++u[i][i];
-  }
-  for (k = n - 1; k >= 0; k--) {
-    for (its = 0; its < max_its; its++) {
-      flag = 1;
-      for (l = k; l >= 0; l--) {
-        nm = l - 1;
-        if ((double)(fabs(rv1[l]) + anorm) == anorm || nm < 0) {
-          flag = 0;
-          break;
-        }
-        if ((double)(fabs(w[nm]) + anorm) == anorm) break;
-      }
-      if (flag) {
-        c = 0.0;
-        s = 1.0;
-        for (i = l; i <= k; i++) {
-          f = s * rv1[i];
-          rv1[i] = c * rv1[i];
-          if ((double)(fabs(f) + anorm) == anorm) break;
-          g = w[i];
-          h = pythag(f, g);
-          w[i] = h;
-          h = 1.0 / h;
-          c = g * h;
-          s = -f * h;
-          for (j = 0; j < m; j++) {
-            y = u[j][nm];
-            z = u[j][i];
-            u[j][nm] = y * c + z * s;
-            u[j][i] = z * c - y * s;
-          }
-        }
-      }
-      z = w[k];
-      if (l == k) {
-        if (z < 0.0) {
-          w[k] = -z;
-          for (j = 0; j < n; j++) v[j][k] = -v[j][k];
-        }
-        break;
-      }
-      if (its == max_its - 1) {
-        return 1;
-      }
-      assert(k > 0);
-      x = w[l];
-      nm = k - 1;
-      y = w[nm];
-      g = rv1[nm];
-      h = rv1[k];
-      f = ((y - z) * (y + z) + (g - h) * (g + h)) / (2.0 * h * y);
-      g = pythag(f, 1.0);
-      f = ((x - z) * (x + z) + h * ((y / (f + sign(g, f))) - h)) / x;
-      c = s = 1.0;
-      for (j = l; j <= nm; j++) {
-        i = j + 1;
-        g = rv1[i];
-        y = w[i];
-        h = s * g;
-        g = c * g;
-        z = pythag(f, h);
-        rv1[j] = z;
-        c = f / z;
-        s = h / z;
-        f = x * c + g * s;
-        g = g * c - x * s;
-        h = y * s;
-        y *= c;
-        for (jj = 0; jj < n; jj++) {
-          x = v[jj][j];
-          z = v[jj][i];
-          v[jj][j] = x * c + z * s;
-          v[jj][i] = z * c - x * s;
-        }
-        z = pythag(f, h);
-        w[j] = z;
-        if (z) {
-          z = 1.0 / z;
-          c = f * z;
-          s = h * z;
-        }
-        f = c * g + s * y;
-        x = c * y - s * g;
-        for (jj = 0; jj < m; jj++) {
-          y = u[jj][j];
-          z = u[jj][i];
-          u[jj][j] = y * c + z * s;
-          u[jj][i] = z * c - y * s;
-        }
-      }
-      rv1[l] = 0.0;
-      rv1[k] = f;
-      w[k] = x;
-    }
-  }
-  aom_free(rv1);
-  return 0;
-}
-
-static int SVD(double *U, double *W, double *V, double *matx, int M, int N) {
-  // Assumes allocation for U is MxN
-  double **nrU = (double **)aom_malloc((M) * sizeof(*nrU));
-  double **nrV = (double **)aom_malloc((N) * sizeof(*nrV));
-  int problem, i;
-
-  problem = !(nrU && nrV);
-  if (!problem) {
-    for (i = 0; i < M; i++) {
-      nrU[i] = &U[i * N];
-    }
-    for (i = 0; i < N; i++) {
-      nrV[i] = &V[i * N];
-    }
-  } else {
-    if (nrU) aom_free(nrU);
-    if (nrV) aom_free(nrV);
-    return 1;
-  }
-
-  /* copy from given matx into nrU */
-  for (i = 0; i < M; i++) {
-    memcpy(&(nrU[i][0]), matx + N * i, N * sizeof(*matx));
-  }
-
-  /* HERE IT IS: do SVD */
-  if (svdcmp(nrU, M, N, W, nrV)) {
-    aom_free(nrU);
-    aom_free(nrV);
-    return 1;
-  }
-
-  /* aom_free Numerical Recipes arrays */
-  aom_free(nrU);
-  aom_free(nrV);
-
-  return 0;
-}
-
-int pseudo_inverse(double *inv, double *matx, const int M, const int N) {
-  double ans;
-  int i, j, k;
-  double *const U = (double *)aom_malloc(M * N * sizeof(*matx));
-  double *const W = (double *)aom_malloc(N * sizeof(*matx));
-  double *const V = (double *)aom_malloc(N * N * sizeof(*matx));
-
-  if (!(U && W && V)) {
-    return 1;
-  }
-  if (SVD(U, W, V, matx, M, N)) {
-    return 1;
-  }
-  for (i = 0; i < N; i++) {
-    if (fabs(W[i]) < TINY_NEAR_ZERO) {
-      return 1;
-    }
-  }
-
-  for (i = 0; i < N; i++) {
-    for (j = 0; j < M; j++) {
-      ans = 0;
-      for (k = 0; k < N; k++) {
-        ans += V[k + N * i] * U[k + N * j] / W[k];
-      }
-      inv[j + M * i] = ans;
-    }
-  }
-  aom_free(U);
-  aom_free(W);
-  aom_free(V);
-  return 0;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // ransac
 typedef int (*IsDegenerateFunc)(double *p);
@@ -351,7 +55,7 @@
   int i;
   for (i = 0; i < n; ++i) {
     const double x = *(points++), y = *(points++);
-    *(proj++) =  mat[3] * x + mat[2] * y + mat[1];
+    *(proj++) = mat[3] * x + mat[2] * y + mat[1];
     *(proj++) = -mat[2] * x + mat[3] * y + mat[0];
     points += stride_points - 2;
     proj += stride_proj - 2;
@@ -594,117 +298,6 @@
   return ret_val;
 }
 
-///////////////////////////////////////////////////////////////////////////////
-
-static void normalize_homography(double *pts, int n, double *T) {
-  // Assume the points are 2d coordinates with scale = 1
-  double *p = pts;
-  double mean[2] = { 0, 0 };
-  double msqe = 0;
-  double scale;
-  int i;
-  for (i = 0; i < n; ++i, p += 2) {
-    mean[0] += p[0];
-    mean[1] += p[1];
-  }
-  mean[0] /= n;
-  mean[1] /= n;
-  for (p = pts, i = 0; i < n; ++i, p += 2) {
-    p[0] -= mean[0];
-    p[1] -= mean[1];
-    msqe += sqrt(p[0] * p[0] + p[1] * p[1]);
-  }
-  msqe /= n;
-  scale = sqrt(2) / msqe;
-  T[0] = scale;
-  T[1] = 0;
-  T[2] = -scale * mean[0];
-  T[3] = 0;
-  T[4] = scale;
-  T[5] = -scale * mean[1];
-  T[6] = 0;
-  T[7] = 0;
-  T[8] = 1;
-  for (p = pts, i = 0; i < n; ++i, p += 2) {
-    p[0] *= scale;
-    p[1] *= scale;
-  }
-}
-
-static void invnormalize_mat(double *T, double *iT) {
-  double is = 1.0 / T[0];
-  double m0 = -T[2] * is;
-  double m1 = -T[5] * is;
-  iT[0] = is;
-  iT[1] = 0;
-  iT[2] = m0;
-  iT[3] = 0;
-  iT[4] = is;
-  iT[5] = m1;
-  iT[6] = 0;
-  iT[7] = 0;
-  iT[8] = 1;
-}
-
-static void denormalize_homography(double *params, double *T1, double *T2) {
-  double iT2[9];
-  double params2[9];
-  invnormalize_mat(T2, iT2);
-  multiply_mat(params, T1, params2, 3, 3, 3);
-  multiply_mat(iT2, params2, params, 3, 3, 3);
-}
-
-static void denormalize_affine(double *params, double *T1, double *T2) {
-  double params_denorm[MAX_PARAMDIM];
-  params_denorm[0] = params[0];
-  params_denorm[1] = params[1];
-  params_denorm[2] = params[4];
-  params_denorm[3] = params[2];
-  params_denorm[4] = params[3];
-  params_denorm[5] = params[5];
-  params_denorm[6] = params_denorm[7] = 0;
-  params_denorm[8] = 1;
-  denormalize_homography(params_denorm, T1, T2);
-  params[0] = params_denorm[5];
-  params[1] = params_denorm[2];
-  params[2] = params_denorm[1];
-  params[3] = params_denorm[0];
-  params[4] = params_denorm[3];
-  params[5] = params_denorm[4];
-}
-
-static void denormalize_rotzoom(double *params, double *T1, double *T2) {
-  double params_denorm[MAX_PARAMDIM];
-  params_denorm[0] = params[0];
-  params_denorm[1] = params[1];
-  params_denorm[2] = params[2];
-  params_denorm[3] = -params[1];
-  params_denorm[4] = params[0];
-  params_denorm[5] = params[3];
-  params_denorm[6] = params_denorm[7] = 0;
-  params_denorm[8] = 1;
-  denormalize_homography(params_denorm, T1, T2);
-  params[0] = params_denorm[5];
-  params[1] = params_denorm[2];
-  params[2] = params_denorm[1];
-  params[3] = params_denorm[0];
-}
-
-static void denormalize_translation(double *params, double *T1, double *T2) {
-  double params_denorm[MAX_PARAMDIM];
-  params_denorm[0] = 1;
-  params_denorm[1] = 0;
-  params_denorm[2] = params[0];
-  params_denorm[3] = 0;
-  params_denorm[4] = 1;
-  params_denorm[5] = params[1];
-  params_denorm[6] = params_denorm[7] = 0;
-  params_denorm[8] = 1;
-  denormalize_homography(params_denorm, T1, T2);
-  params[0] = params_denorm[5];
-  params[1] = params_denorm[2];
-}
-
 static int is_collinear3(double *p1, double *p2, double *p3) {
   static const double collinear_eps = 1e-3;
   const double v =
@@ -725,185 +318,6 @@
          is_collinear3(p, p + 4, p + 6) || is_collinear3(p + 2, p + 4, p + 6);
 }
 
-int find_translation(const int np, double *pts1, double *pts2, double *mat) {
-  int i;
-  double sx, sy, dx, dy;
-  double sumx, sumy;
-
-  double T1[9], T2[9];
-  normalize_homography(pts1, np, T1);
-  normalize_homography(pts2, np, T2);
-
-  sumx = 0;
-  sumy = 0;
-  for (i = 0; i < np; ++i) {
-    dx = *(pts2++);
-    dy = *(pts2++);
-    sx = *(pts1++);
-    sy = *(pts1++);
-
-    sumx += dx - sx;
-    sumy += dy - sy;
-  }
-  mat[0] = sumx / np;
-  mat[1] = sumy / np;
-  denormalize_translation(mat, T1, T2);
-  return 0;
-}
-
-int find_rotzoom(const int np, double *pts1, double *pts2, double *mat) {
-  const int np2 = np * 2;
-  double *a = (double *)aom_malloc(sizeof(*a) * np2 * 9);
-  double *b = a + np2 * 4;
-  double *temp = b + np2;
-  int i;
-  double sx, sy, dx, dy;
-
-  double T1[9], T2[9];
-  normalize_homography(pts1, np, T1);
-  normalize_homography(pts2, np, T2);
-
-  for (i = 0; i < np; ++i) {
-    dx = *(pts2++);
-    dy = *(pts2++);
-    sx = *(pts1++);
-    sy = *(pts1++);
-
-    a[i * 2 * 4 + 0] = sx;
-    a[i * 2 * 4 + 1] = sy;
-    a[i * 2 * 4 + 2] = 1;
-    a[i * 2 * 4 + 3] = 0;
-    a[(i * 2 + 1) * 4 + 0] = sy;
-    a[(i * 2 + 1) * 4 + 1] = -sx;
-    a[(i * 2 + 1) * 4 + 2] = 0;
-    a[(i * 2 + 1) * 4 + 3] = 1;
-
-    b[2 * i] = dx;
-    b[2 * i + 1] = dy;
-  }
-  if (pseudo_inverse(temp, a, np2, 4)) {
-    aom_free(a);
-    return 1;
-  }
-  multiply_mat(temp, b, mat, 4, np2, 1);
-  denormalize_rotzoom(mat, T1, T2);
-  aom_free(a);
-  return 0;
-}
-
-int find_affine(const int np, double *pts1, double *pts2, double *mat) {
-  const int np2 = np * 2;
-  double *a = (double *)aom_malloc(sizeof(*a) * np2 * 13);
-  double *b = a + np2 * 6;
-  double *temp = b + np2;
-  int i;
-  double sx, sy, dx, dy;
-
-  double T1[9], T2[9];
-  normalize_homography(pts1, np, T1);
-  normalize_homography(pts2, np, T2);
-
-  for (i = 0; i < np; ++i) {
-    dx = *(pts2++);
-    dy = *(pts2++);
-    sx = *(pts1++);
-    sy = *(pts1++);
-
-    a[i * 2 * 6 + 0] = sx;
-    a[i * 2 * 6 + 1] = sy;
-    a[i * 2 * 6 + 2] = 0;
-    a[i * 2 * 6 + 3] = 0;
-    a[i * 2 * 6 + 4] = 1;
-    a[i * 2 * 6 + 5] = 0;
-    a[(i * 2 + 1) * 6 + 0] = 0;
-    a[(i * 2 + 1) * 6 + 1] = 0;
-    a[(i * 2 + 1) * 6 + 2] = sx;
-    a[(i * 2 + 1) * 6 + 3] = sy;
-    a[(i * 2 + 1) * 6 + 4] = 0;
-    a[(i * 2 + 1) * 6 + 5] = 1;
-
-    b[2 * i] = dx;
-    b[2 * i + 1] = dy;
-  }
-  if (pseudo_inverse(temp, a, np2, 6)) {
-    aom_free(a);
-    return 1;
-  }
-  multiply_mat(temp, b, mat, 6, np2, 1);
-  denormalize_affine(mat, T1, T2);
-  aom_free(a);
-  return 0;
-}
-
-int find_homography(const int np, double *pts1, double *pts2, double *mat) {
-  // Implemented from Peter Kovesi's normalized implementation
-  const int np3 = np * 3;
-  double *a = (double *)aom_malloc(sizeof(*a) * np3 * 18);
-  double *U = a + np3 * 9;
-  double S[9], V[9 * 9];
-  int i, mini;
-  double sx, sy, dx, dy;
-  double T1[9], T2[9];
-
-  normalize_homography(pts1, np, T1);
-  normalize_homography(pts2, np, T2);
-
-  for (i = 0; i < np; ++i) {
-    dx = *(pts2++);
-    dy = *(pts2++);
-    sx = *(pts1++);
-    sy = *(pts1++);
-
-    a[i * 3 * 9 + 0] = a[i * 3 * 9 + 1] = a[i * 3 * 9 + 2] = 0;
-    a[i * 3 * 9 + 3] = -sx;
-    a[i * 3 * 9 + 4] = -sy;
-    a[i * 3 * 9 + 5] = -1;
-    a[i * 3 * 9 + 6] = dy * sx;
-    a[i * 3 * 9 + 7] = dy * sy;
-    a[i * 3 * 9 + 8] = dy;
-
-    a[(i * 3 + 1) * 9 + 0] = sx;
-    a[(i * 3 + 1) * 9 + 1] = sy;
-    a[(i * 3 + 1) * 9 + 2] = 1;
-    a[(i * 3 + 1) * 9 + 3] = a[(i * 3 + 1) * 9 + 4] = a[(i * 3 + 1) * 9 + 5] =
-        0;
-    a[(i * 3 + 1) * 9 + 6] = -dx * sx;
-    a[(i * 3 + 1) * 9 + 7] = -dx * sy;
-    a[(i * 3 + 1) * 9 + 8] = -dx;
-
-    a[(i * 3 + 2) * 9 + 0] = -dy * sx;
-    a[(i * 3 + 2) * 9 + 1] = -dy * sy;
-    a[(i * 3 + 2) * 9 + 2] = -dy;
-    a[(i * 3 + 2) * 9 + 3] = dx * sx;
-    a[(i * 3 + 2) * 9 + 4] = dx * sy;
-    a[(i * 3 + 2) * 9 + 5] = dx;
-    a[(i * 3 + 2) * 9 + 6] = a[(i * 3 + 2) * 9 + 7] = a[(i * 3 + 2) * 9 + 8] =
-        0;
-  }
-
-  if (SVD(U, S, V, a, np3, 9)) {
-    aom_free(a);
-    return 1;
-  } else {
-    double minS = 1e12;
-    mini = -1;
-    for (i = 0; i < 9; ++i) {
-      if (S[i] < minS) {
-        minS = S[i];
-        mini = i;
-      }
-    }
-  }
-
-  for (i = 0; i < 9; i++) mat[i] = V[i * 9 + mini];
-  denormalize_homography(mat, T1, T2);
-  aom_free(a);
-  if (mat[8] == 0.0) {
-    return 1;
-  }
-  return 0;
-}
-
 int ransac_translation(double *matched_points, int npoints,
                        int *number_of_inliers, int *best_inlier_mask,
                        double *best_params) {