vp8/encoder/treewriter.c

   1 /*
   2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10
  11
  12 #include "treewriter.h"
  13
  14 static void cost(
  15     int *const C,
  16     vp8_tree T,
  17     const vp8_prob *const P,
  18     int i,
  19     int c
  20 )
  21 {
  22     const vp8_prob p = P [i>>1];
  23
  24     do
  25     {
  26         const vp8_tree_index j = T[i];
  27         const int d = c + vp8_cost_bit(p, i & 1);
  28
  29         if (j <= 0)
  30             C[-j] = d;
  31         else
  32             cost(C, T, P, j, d);
  33     }
  34     while (++i & 1);
  35 }
  36 void vp8_cost_tokens(int *c, const vp8_prob *p, vp8_tree t)
  37 {
  38     cost(c, t, p, 0, 0);
  39 }