godot/thirdparty/libwebp/src/dec/tree_dec.c

// Copyright 2010 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING 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.
// -----------------------------------------------------------------------------
//
// Coding trees and probas
//
// Author: Skal ([email protected])

#include "src/dec/vp8i_dec.h"
#include "src/dsp/cpu.h"
#include "src/utils/bit_reader_inl_utils.h"

#if !defined(USE_GENERIC_TREE)
#if !defined(__arm__) && !defined(_M_ARM) && !WEBP_AARCH64
// using a table is ~1-2% slower on ARM. Prefer the coded-tree approach then.
#define USE_GENERIC_TREE …
#else
#define USE_GENERIC_TREE …
#endif
#endif  // USE_GENERIC_TREE

#if (USE_GENERIC_TREE == 1)
static const int8_t kYModesIntra4[18] = …;
#endif

//------------------------------------------------------------------------------
// Default probabilities

// Paragraph 13.5
static const uint8_t
  CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS] = …;

// Paragraph 11.5
static const uint8_t kBModesProba[NUM_BMODES][NUM_BMODES][NUM_BMODES - 1] = …;

void VP8ResetProba(VP8Proba* const proba) { … }

static void ParseIntraMode(VP8BitReader* const br,
                           VP8Decoder* const dec, int mb_x) { … }

int VP8ParseIntraModeRow(VP8BitReader* const br, VP8Decoder* const dec) { … }

//------------------------------------------------------------------------------
// Paragraph 13

static const uint8_t
    CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS] = …;

// Paragraph 9.9

static const uint8_t kBands[16 + 1] = …;

void VP8ParseProba(VP8BitReader* const br, VP8Decoder* const dec) { … }