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-rw-r--r--core/src/fxcodec/jbig2/JBig2_HuffmanDecoder.cpp55
1 files changed, 55 insertions, 0 deletions
diff --git a/core/src/fxcodec/jbig2/JBig2_HuffmanDecoder.cpp b/core/src/fxcodec/jbig2/JBig2_HuffmanDecoder.cpp
new file mode 100644
index 0000000000..8199fe7c21
--- /dev/null
+++ b/core/src/fxcodec/jbig2/JBig2_HuffmanDecoder.cpp
@@ -0,0 +1,55 @@
+// 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 "JBig2_HuffmanDecoder.h"
+CJBig2_HuffmanDecoder::CJBig2_HuffmanDecoder(CJBig2_BitStream *pStream)
+{
+ m_pStream = pStream;
+}
+CJBig2_HuffmanDecoder::~CJBig2_HuffmanDecoder()
+{
+}
+int CJBig2_HuffmanDecoder::decodeAValue(CJBig2_HuffmanTable *pTable, int *nResult)
+{
+ int nVal, nTmp, i, nBits;
+ nVal = 0;
+ nBits = 0;
+ while(1) {
+ if(m_pStream->read1Bit(&nTmp) == -1) {
+ return -1;
+ }
+ nVal = (nVal << 1) | nTmp;
+ nBits ++;
+ for(i = 0; i < pTable->NTEMP; i++) {
+ if((pTable->PREFLEN[i] == nBits) && (pTable->CODES[i] == nVal)) {
+ if((pTable->HTOOB == 1) && (i == pTable->NTEMP - 1)) {
+ return JBIG2_OOB;
+ }
+ if(m_pStream->readNBits(pTable->RANGELEN[i], &nTmp) == -1) {
+ return -1;
+ }
+ if(pTable->HTOOB) {
+ if(i == pTable->NTEMP - 3) {
+ *nResult = pTable->RANGELOW[i] - nTmp;
+ return 0;
+ } else {
+ *nResult = pTable->RANGELOW[i] + nTmp;
+ return 0;
+ }
+ } else {
+ if(i == pTable->NTEMP - 2) {
+ *nResult = pTable->RANGELOW[i] - nTmp;
+ return 0;
+ } else {
+ *nResult = pTable->RANGELOW[i] + nTmp;
+ return 0;
+ }
+ }
+ }
+ }
+ }
+ return -2;
+}