xref: /aosp_15_r20/external/libvpx/vp8/encoder/treewriter.c (revision fb1b10ab9aebc7c7068eedab379b749d7e3900be)

/*
 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "treewriter.h"

static void cost(int *const C, vp8_tree T, const vp8_prob *const P, int i,
                 int c) {
  const vp8_prob p = P[i >> 1];

  do {
    const vp8_tree_index j = T[i];
    const int d = c + vp8_cost_bit(p, i & 1);

    if (j <= 0) {
      C[-j] = d;
    } else {
      cost(C, T, P, j, d);
    }
  } while (++i & 1);
}
void vp8_cost_tokens(int *c, const vp8_prob *p, vp8_tree t) {
  cost(c, t, p, 0, 0);
}
void vp8_cost_tokens2(int *c, const vp8_prob *p, vp8_tree t, int start) {
  cost(c, t, p, start, 0);
}