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diff --git a/media/libaom/src/av1/encoder/global_motion.c b/media/libaom/src/av1/encoder/global_motion.c
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+/*
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <memory.h>
+#include <math.h>
+#include <assert.h>
+
+#include "av1/encoder/global_motion.h"
+
+#include "av1/common/warped_motion.h"
+
+#include "av1/encoder/segmentation.h"
+#include "av1/encoder/corner_detect.h"
+#include "av1/encoder/corner_match.h"
+#include "av1/encoder/ransac.h"
+
+#define MAX_CORNERS 4096
+#define MIN_INLIER_PROB 0.1
+
+#define MIN_TRANS_THRESH (1 * GM_TRANS_DECODE_FACTOR)
+
+// Border over which to compute the global motion
+#define ERRORADV_BORDER 0
+
+static const double erroradv_tr[] = { 0.65, 0.60, 0.55 };
+static const double erroradv_prod_tr[] = { 20000, 18000, 16000 };
+
+int is_enough_erroradvantage(double best_erroradvantage, int params_cost,
+ int erroradv_type) {
+ assert(erroradv_type < GM_ERRORADV_TR_TYPES);
+ return best_erroradvantage < erroradv_tr[erroradv_type] &&
+ best_erroradvantage * params_cost < erroradv_prod_tr[erroradv_type];
+}
+
+static void convert_to_params(const double *params, int32_t *model) {
+ int i;
+ int alpha_present = 0;
+ model[0] = (int32_t)floor(params[0] * (1 << GM_TRANS_PREC_BITS) + 0.5);
+ model[1] = (int32_t)floor(params[1] * (1 << GM_TRANS_PREC_BITS) + 0.5);
+ model[0] = (int32_t)clamp(model[0], GM_TRANS_MIN, GM_TRANS_MAX) *
+ GM_TRANS_DECODE_FACTOR;
+ model[1] = (int32_t)clamp(model[1], GM_TRANS_MIN, GM_TRANS_MAX) *
+ GM_TRANS_DECODE_FACTOR;
+
+ for (i = 2; i < 6; ++i) {
+ const int diag_value = ((i == 2 || i == 5) ? (1 << GM_ALPHA_PREC_BITS) : 0);
+ model[i] = (int32_t)floor(params[i] * (1 << GM_ALPHA_PREC_BITS) + 0.5);
+ model[i] =
+ (int32_t)clamp(model[i] - diag_value, GM_ALPHA_MIN, GM_ALPHA_MAX);
+ alpha_present |= (model[i] != 0);
+ model[i] = (model[i] + diag_value) * GM_ALPHA_DECODE_FACTOR;
+ }
+ for (; i < 8; ++i) {
+ model[i] = (int32_t)floor(params[i] * (1 << GM_ROW3HOMO_PREC_BITS) + 0.5);
+ model[i] = (int32_t)clamp(model[i], GM_ROW3HOMO_MIN, GM_ROW3HOMO_MAX) *
+ GM_ROW3HOMO_DECODE_FACTOR;
+ alpha_present |= (model[i] != 0);
+ }
+
+ if (!alpha_present) {
+ if (abs(model[0]) < MIN_TRANS_THRESH && abs(model[1]) < MIN_TRANS_THRESH) {
+ model[0] = 0;
+ model[1] = 0;
+ }
+ }
+}
+
+void convert_model_to_params(const double *params, WarpedMotionParams *model) {
+ convert_to_params(params, model->wmmat);
+ model->wmtype = get_gmtype(model);
+ model->invalid = 0;
+}
+
+// Adds some offset to a global motion parameter and handles
+// all of the necessary precision shifts, clamping, and
+// zero-centering.
+static int32_t add_param_offset(int param_index, int32_t param_value,
+ int32_t offset) {
+ const int scale_vals[3] = { GM_TRANS_PREC_DIFF, GM_ALPHA_PREC_DIFF,
+ GM_ROW3HOMO_PREC_DIFF };
+ const int clamp_vals[3] = { GM_TRANS_MAX, GM_ALPHA_MAX, GM_ROW3HOMO_MAX };
+ // type of param: 0 - translation, 1 - affine, 2 - homography
+ const int param_type = (param_index < 2 ? 0 : (param_index < 6 ? 1 : 2));
+ const int is_one_centered = (param_index == 2 || param_index == 5);
+
+ // Make parameter zero-centered and offset the shift that was done to make
+ // it compatible with the warped model
+ param_value = (param_value - (is_one_centered << WARPEDMODEL_PREC_BITS)) >>
+ scale_vals[param_type];
+ // Add desired offset to the rescaled/zero-centered parameter
+ param_value += offset;
+ // Clamp the parameter so it does not overflow the number of bits allotted
+ // to it in the bitstream
+ param_value = (int32_t)clamp(param_value, -clamp_vals[param_type],
+ clamp_vals[param_type]);
+ // Rescale the parameter to WARPEDMODEL_PRECISION_BITS so it is compatible
+ // with the warped motion library
+ param_value *= (1 << scale_vals[param_type]);
+
+ // Undo the zero-centering step if necessary
+ return param_value + (is_one_centered << WARPEDMODEL_PREC_BITS);
+}
+
+static void force_wmtype(WarpedMotionParams *wm, TransformationType wmtype) {
+ switch (wmtype) {
+ case IDENTITY:
+ wm->wmmat[0] = 0;
+ wm->wmmat[1] = 0;
+ AOM_FALLTHROUGH_INTENDED;
+ case TRANSLATION:
+ wm->wmmat[2] = 1 << WARPEDMODEL_PREC_BITS;
+ wm->wmmat[3] = 0;
+ AOM_FALLTHROUGH_INTENDED;
+ case ROTZOOM:
+ wm->wmmat[4] = -wm->wmmat[3];
+ wm->wmmat[5] = wm->wmmat[2];
+ AOM_FALLTHROUGH_INTENDED;
+ case AFFINE: wm->wmmat[6] = wm->wmmat[7] = 0; break;
+ default: assert(0);
+ }
+ wm->wmtype = wmtype;
+}
+
+int64_t refine_integerized_param(WarpedMotionParams *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) {
+ static const int max_trans_model_params[TRANS_TYPES] = { 0, 2, 4, 6 };
+ const int border = ERRORADV_BORDER;
+ int i = 0, p;
+ int n_params = max_trans_model_params[wmtype];
+ int32_t *param_mat = wm->wmmat;
+ int64_t step_error, best_error;
+ int32_t step;
+ int32_t *param;
+ int32_t curr_param;
+ int32_t best_param;
+
+ force_wmtype(wm, wmtype);
+ best_error = av1_warp_error(wm, use_hbd, bd, ref, r_width, r_height, r_stride,
+ dst + border * d_stride + border, border, border,
+ d_width - 2 * border, d_height - 2 * border,
+ d_stride, 0, 0, best_frame_error);
+ best_error = AOMMIN(best_error, best_frame_error);
+ step = 1 << (n_refinements - 1);
+ for (i = 0; i < n_refinements; i++, step >>= 1) {
+ for (p = 0; p < n_params; ++p) {
+ int step_dir = 0;
+ // Skip searches for parameters that are forced to be 0
+ param = param_mat + p;
+ curr_param = *param;
+ best_param = curr_param;
+ // look to the left
+ *param = add_param_offset(p, curr_param, -step);
+ step_error =
+ av1_warp_error(wm, use_hbd, bd, ref, r_width, r_height, r_stride,
+ dst + border * d_stride + border, border, border,
+ d_width - 2 * border, d_height - 2 * border, d_stride,
+ 0, 0, best_error);
+ if (step_error < best_error) {
+ best_error = step_error;
+ best_param = *param;
+ step_dir = -1;
+ }
+
+ // look to the right
+ *param = add_param_offset(p, curr_param, step);
+ step_error =
+ av1_warp_error(wm, use_hbd, bd, ref, r_width, r_height, r_stride,
+ dst + border * d_stride + border, border, border,
+ d_width - 2 * border, d_height - 2 * border, d_stride,
+ 0, 0, best_error);
+ if (step_error < best_error) {
+ best_error = step_error;
+ best_param = *param;
+ step_dir = 1;
+ }
+ *param = best_param;
+
+ // look to the direction chosen above repeatedly until error increases
+ // for the biggest step size
+ while (step_dir) {
+ *param = add_param_offset(p, best_param, step * step_dir);
+ step_error =
+ av1_warp_error(wm, use_hbd, bd, ref, r_width, r_height, r_stride,
+ dst + border * d_stride + border, border, border,
+ d_width - 2 * border, d_height - 2 * border,
+ d_stride, 0, 0, best_error);
+ if (step_error < best_error) {
+ best_error = step_error;
+ best_param = *param;
+ } else {
+ *param = best_param;
+ step_dir = 0;
+ }
+ }
+ }
+ }
+ force_wmtype(wm, wmtype);
+ wm->wmtype = get_gmtype(wm);
+ return best_error;
+}
+
+static INLINE RansacFunc 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 unsigned char *downconvert_frame(YV12_BUFFER_CONFIG *frm,
+ int bit_depth) {
+ int i, j;
+ uint16_t *orig_buf = CONVERT_TO_SHORTPTR(frm->y_buffer);
+ uint8_t *buf_8bit = frm->y_buffer_8bit;
+ assert(buf_8bit);
+ if (!frm->buf_8bit_valid) {
+ for (i = 0; i < frm->y_height; ++i) {
+ for (j = 0; j < frm->y_width; ++j) {
+ buf_8bit[i * frm->y_stride + j] =
+ orig_buf[i * frm->y_stride + j] >> (bit_depth - 8);
+ }
+ }
+ frm->buf_8bit_valid = 1;
+ }
+ return buf_8bit;
+}
+
+int compute_global_motion_feature_based(TransformationType type,
+ YV12_BUFFER_CONFIG *frm,
+ YV12_BUFFER_CONFIG *ref, int bit_depth,
+ int *num_inliers_by_motion,
+ double *params_by_motion,
+ int num_motions) {
+ int i;
+ int num_frm_corners, num_ref_corners;
+ int num_correspondences;
+ int *correspondences;
+ int frm_corners[2 * MAX_CORNERS], ref_corners[2 * MAX_CORNERS];
+ unsigned char *frm_buffer = frm->y_buffer;
+ unsigned char *ref_buffer = ref->y_buffer;
+ RansacFunc ransac = get_ransac_type(type);
+
+ if (frm->flags & YV12_FLAG_HIGHBITDEPTH) {
+ // The frame buffer is 16-bit, so we need to convert to 8 bits for the
+ // following code. We cache the result until the frame is released.
+ frm_buffer = downconvert_frame(frm, bit_depth);
+ }
+ if (ref->flags & YV12_FLAG_HIGHBITDEPTH) {
+ ref_buffer = downconvert_frame(ref, bit_depth);
+ }
+
+ // compute interest points in images using FAST features
+ num_frm_corners = fast_corner_detect(frm_buffer, frm->y_width, frm->y_height,
+ frm->y_stride, frm_corners, MAX_CORNERS);
+ num_ref_corners = fast_corner_detect(ref_buffer, ref->y_width, ref->y_height,
+ ref->y_stride, ref_corners, MAX_CORNERS);
+
+ // find correspondences between the two images
+ correspondences =
+ (int *)malloc(num_frm_corners * 4 * sizeof(*correspondences));
+ num_correspondences = determine_correspondence(
+ frm_buffer, (int *)frm_corners, num_frm_corners, ref_buffer,
+ (int *)ref_corners, num_ref_corners, frm->y_width, frm->y_height,
+ frm->y_stride, ref->y_stride, correspondences);
+
+ ransac(correspondences, num_correspondences, num_inliers_by_motion,
+ params_by_motion, num_motions);
+
+ free(correspondences);
+
+ // Set num_inliers = 0 for motions with too few inliers so they are ignored.
+ for (i = 0; i < num_motions; ++i) {
+ if (num_inliers_by_motion[i] < MIN_INLIER_PROB * num_correspondences) {
+ num_inliers_by_motion[i] = 0;
+ }
+ }
+
+ // Return true if any one of the motions has inliers.
+ for (i = 0; i < num_motions; ++i) {
+ if (num_inliers_by_motion[i] > 0) return 1;
+ }
+ return 0;
+}