From 764ec513eecbebd12781bcc96ce81ed5e736ee92 Mon Sep 17 00:00:00 2001 From: Dan Sinclair Date: Mon, 14 Mar 2016 13:35:12 -0400 Subject: Move core/src/ up to core/. This CL moves the core/src/ files up to core/ and fixes up the include guards, includes and build files. R=tsepez@chromium.org Review URL: https://codereview.chromium.org/1800523005 . --- core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp | 92 ++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp (limited to 'core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp') diff --git a/core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp b/core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp new file mode 100644 index 0000000000..63594672c7 --- /dev/null +++ b/core/fxcodec/jbig2/JBig2_ArithIntDecoder.cpp @@ -0,0 +1,92 @@ +// Copyright 2014 PDFium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com + +#include "core/fxcodec/jbig2/JBig2_ArithIntDecoder.h" + +#include + +#include "core/include/fxcrt/fx_basic.h" + +namespace { + +int ShiftOr(int val, int bitwise_or_val) { + return (val << 1) | bitwise_or_val; +} + +const struct ArithIntDecodeData { + int nNeedBits; + int nValue; +} g_ArithIntDecodeData[] = { + {2, 0}, {4, 4}, {6, 20}, {8, 84}, {12, 340}, {32, 4436}, +}; + +size_t RecursiveDecode(CJBig2_ArithDecoder* decoder, + std::vector* context, + int* prev, + size_t depth) { + static const size_t kDepthEnd = FX_ArraySize(g_ArithIntDecodeData) - 1; + if (depth == kDepthEnd) + return kDepthEnd; + + JBig2ArithCtx* pCX = &(*context)[*prev]; + int D = decoder->DECODE(pCX); + *prev = ShiftOr(*prev, D); + if (!D) + return depth; + return RecursiveDecode(decoder, context, prev, depth + 1); +} + +} // namespace + +CJBig2_ArithIntDecoder::CJBig2_ArithIntDecoder() { + m_IAx.resize(512); +} + +CJBig2_ArithIntDecoder::~CJBig2_ArithIntDecoder() {} + +bool CJBig2_ArithIntDecoder::decode(CJBig2_ArithDecoder* pArithDecoder, + int* nResult) { + int PREV = 1; + const int S = pArithDecoder->DECODE(&m_IAx[PREV]); + PREV = ShiftOr(PREV, S); + + const size_t nDecodeDataIndex = + RecursiveDecode(pArithDecoder, &m_IAx, &PREV, 0); + + int nTemp = 0; + for (int i = 0; i < g_ArithIntDecodeData[nDecodeDataIndex].nNeedBits; ++i) { + int D = pArithDecoder->DECODE(&m_IAx[PREV]); + PREV = ShiftOr(PREV, D); + if (PREV >= 256) + PREV = (PREV & 511) | 256; + nTemp = ShiftOr(nTemp, D); + } + int nValue = g_ArithIntDecodeData[nDecodeDataIndex].nValue; + nValue += nTemp; + if (S == 1 && nValue > 0) + nValue = -nValue; + + *nResult = nValue; + return S != 1 || nValue != 0; +} + +CJBig2_ArithIaidDecoder::CJBig2_ArithIaidDecoder(unsigned char SBSYMCODELENA) + : SBSYMCODELEN(SBSYMCODELENA) { + m_IAID.resize(1 << SBSYMCODELEN); +} + +CJBig2_ArithIaidDecoder::~CJBig2_ArithIaidDecoder() {} + +void CJBig2_ArithIaidDecoder::decode(CJBig2_ArithDecoder* pArithDecoder, + FX_DWORD* nResult) { + int PREV = 1; + for (unsigned char i = 0; i < SBSYMCODELEN; ++i) { + JBig2ArithCtx* pCX = &m_IAID[PREV]; + int D = pArithDecoder->DECODE(pCX); + PREV = ShiftOr(PREV, D); + } + *nResult = PREV - (1 << SBSYMCODELEN); +} -- cgit v1.2.3