vpx/vp9/encoder/vp9_treewriter.c
Deb Mukherjee eb6ef2417f Coding con-zero count rather than EOB for coeffs
This patch revamps the entropy coding of coefficients to code first
a non-zero count per coded block and correspondingly remove the EOB
token from the token set.

STATUS:
Main encode/decode code achieving encode/decode sync - done.
Forward and backward probability updates to the nzcs - done.
Rd costing updates for nzcs - done.
Note: The dynamic progrmaming apporach used in trellis quantization
is not exactly compatible with nzcs. A suboptimal approach has been
used instead where branch costs are updated to account for changes
in the nzcs.

TODO:
Training the default probs/counts for nzcs

Change-Id: I951bc1e22f47885077a7453a09b0493daa77883d
2013-03-07 07:20:30 -08:00

41 lines
957 B
C

/*
* 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 "vp9/encoder/vp9_treewriter.h"
static void cost(
int *const C,
vp9_tree T,
const vp9_prob *const P,
int i,
int c
) {
const vp9_prob p = P [i >> 1];
do {
const vp9_tree_index j = T[i];
const int d = c + vp9_cost_bit(p, i & 1);
if (j <= 0)
C[-j] = d;
else
cost(C, T, P, j, d);
} while (++i & 1);
}
void vp9_cost_tokens(int *c, const vp9_prob *p, vp9_tree t) {
cost(c, t, p, 0, 0);
}
void vp9_cost_tokens_skip(int *c, const vp9_prob *p, vp9_tree t) {
c[0] = 0;
cost(c, t, p, 2, 0);
}