From c92229b7149a506a81d733f06198b1c284d9853f Mon Sep 17 00:00:00 2001 From: morkt Date: Mon, 12 Oct 2015 06:50:20 +0400 Subject: [PATCH] implemented ERISA decoder for ERI images. --- ArcFormats/Entis/EriReader.cs | 272 ++++++++++++++++++++++++++++++++-- 1 file changed, 259 insertions(+), 13 deletions(-) diff --git a/ArcFormats/Entis/EriReader.cs b/ArcFormats/Entis/EriReader.cs index ef297bed..f431a2cb 100644 --- a/ArcFormats/Entis/EriReader.cs +++ b/ArcFormats/Entis/EriReader.cs @@ -46,6 +46,7 @@ namespace GameRes.Formats.Entis int[] m_pArrangeTable = new int[4]; HuffmanTree m_pHuffmanTree; + ErisaProbModel m_pProbERISA; PtrProcedure[] m_pfnColorOperation; @@ -95,7 +96,6 @@ namespace GameRes.Formats.Entis switch (m_info.Architecture) { case EriCode.Nemesis: - throw new NotSupportedException ("Not supported ERI compression"); case EriCode.RunlengthHuffman: case EriCode.RunlengthGamma: break; @@ -143,15 +143,15 @@ namespace GameRes.Formats.Entis { m_pHuffmanTree = new HuffmanTree(); } - /* else if (EriCode.Nemesis == m_info.Architecture) { - m_pProbERISA = new ERISA_PROB_MODEL ; + m_pProbERISA = new ErisaProbModel(); } - */ } if (EriCode.RunlengthHuffman == m_info.Architecture) m_context = new HuffmanDecodeContext (0x10000); + else if (EriCode.Nemesis == m_info.Architecture) + m_context = new ProbDecodeContext (0x10000); else m_context = new RLEDecodeContext (0x10000); } @@ -283,18 +283,18 @@ namespace GameRes.Formats.Entis var pfnRestoreFunc = GetLLRestoreFunc (m_info.FormatType, m_info.BPP); if (null == pfnRestoreFunc) throw new InvalidFormatException(); - /* + if (EriCode.Nemesis == m_info.Architecture) { Debug.Assert (m_pProbERISA != null); m_pProbERISA.Initialize(); } - */ int i; int ptrNextOperation = 0; // index within m_ptrOperations if ((0 != (fEncodeType & 0x01)) && (m_nChannelCount >= 3)) { - Debug.Assert (m_info.Architecture != EriCode.Nemesis); + if (m_info.Architecture == EriCode.Nemesis) + throw new InvalidFormatException(); int nAllBlockCount = (int)(m_nWidthBlocks * m_nHeightBlocks); for (i = 0; i < nAllBlockCount; i++) { @@ -323,13 +323,11 @@ namespace GameRes.Formats.Entis { (context as HuffmanDecodeContext).PrepareToDecodeERINACode(); } - /* else { Debug.Assert (EriCode.Nemesis == m_info.Architecture); - context.PrepareToDecodeERISACode(); + (context as ProbDecodeContext).PrepareToDecodeERISACode(); } - */ int nWidthSamples = (int)(m_nChannelCount * m_nWidthBlocks * m_nBlockSize); for (i = 0; i < nWidthSamples; ++i) m_ptrLineBuf[i] = 0; @@ -367,12 +365,10 @@ namespace GameRes.Formats.Entis { dwOperationCode = (uint)(context as HuffmanDecodeContext).GetHuffmanCode (m_pHuffmanTree); } - /* else if (m_info.Architecture == EriCode.Nemesis) { - dwOperationCode = context.DecodeERISACode (m_pProbERISA); + dwOperationCode = (uint)(context as ProbDecodeContext).DecodeERISACode (m_pProbERISA); } - */ else { Debug.Assert (EriCode.RunlengthGamma == m_info.Architecture); @@ -1369,4 +1365,254 @@ namespace GameRes.Formats.Entis return nCode; } } + + internal class ProbDecodeContext : RLEDecodeContext + { + uint m_dwCodeRegister; + uint m_dwAugendRegister; + int m_nPostBitCount; + byte[] m_bytLastSymbol = new byte[4]; + + ErisaProbModel m_pPhraseLenProb = new ErisaProbModel(); + ErisaProbModel m_pPhraseIndexProb = new ErisaProbModel(); + ErisaProbModel m_pRunLenProb = new ErisaProbModel(); + ErisaProbModel m_pLastERISAProb; + ErisaProbModel[] m_ppTableERISA; + + public ProbDecodeContext (uint nBufferingSize) : base (nBufferingSize) + { + } + + public void PrepareToDecodeERISACode () + { + if (null == m_ppTableERISA) + { + m_ppTableERISA = new ErisaProbModel[0x101]; + for (int i = 0; i < 0x101; ++i) + { + m_ppTableERISA[i] = new ErisaProbModel(); + m_ppTableERISA[i].Initialize(); + } + } + m_pLastERISAProb = m_ppTableERISA[0]; + m_pPhraseLenProb.Initialize(); + m_pPhraseIndexProb.Initialize(); + m_pRunLenProb.Initialize(); + + InitializeERISACode(); + } + + public override uint DecodeBytes (Array ptrDst, uint nCount) + { + return DecodeERISACodeBytes (ptrDst as sbyte[], nCount); + } + + uint DecodeERISACodeBytes (sbyte[] ptrDst, uint nCount) + { + var pProb = m_pLastERISAProb; + int nSymbol, iSym; + uint i = 0; + while (i < nCount) + { + if (m_nLength > 0) + { + uint nCurrent = nCount - i; + if (nCurrent > m_nLength) + nCurrent = m_nLength; + m_nLength -= nCurrent; + for (uint j = 0; j < nCurrent; j++) + { + ptrDst[i++] = 0; + } + continue; + } + iSym = DecodeERISACodeIndex (pProb); + if (iSym < 0) + break; + nSymbol = pProb.SymTable[iSym].Symbol; + pProb.IncreaseSymbol (iSym); + ptrDst[i++] = (sbyte)nSymbol; + + if (0 == nSymbol) + { + iSym = DecodeERISACodeIndex (m_pRunLenProb); + if (iSym < 0) + break; + m_nLength = (uint)m_pRunLenProb.SymTable[iSym].Symbol; + m_pRunLenProb.IncreaseSymbol (iSym); + } + pProb = m_ppTableERISA[nSymbol & 0xFF]; + } + m_pLastERISAProb = pProb; + return i; + } + + void InitializeERISACode () + { + m_nLength = 0; + m_dwCodeRegister = GetNBits (32); + m_dwAugendRegister = 0xFFFF; + m_nPostBitCount = 0; + } + + public int DecodeERISACode (ErisaProbModel pModel) + { + int iSym = DecodeERISACodeIndex (pModel); + int nSymbol = ErisaProbModel.EscCode; + if (iSym >= 0) + { + nSymbol = pModel.SymTable[iSym].Symbol; + pModel.IncreaseSymbol (iSym); + } + return nSymbol; + } + + int DecodeERISACodeIndex (ErisaProbModel pModel) + { + uint dwAcc = m_dwCodeRegister * pModel.TotalCount / m_dwAugendRegister; + if (dwAcc >= ErisaProbModel.TotalLimit) + { + return -1; + } + int iSym = 0; + ushort wAcc = (ushort)dwAcc; + ushort wFs = 0; + ushort wOccured; + for (;;) + { + wOccured = pModel.SymTable[iSym].Occured; + if (wAcc < wOccured) + break; + wAcc -= wOccured; + wFs += wOccured; + if (++iSym >= pModel.SymbolSorts) + return -1; + } + m_dwCodeRegister -= (m_dwAugendRegister * wFs + pModel.TotalCount - 1) / pModel.TotalCount; + m_dwAugendRegister = m_dwAugendRegister * wOccured / pModel.TotalCount; + Debug.Assert (m_dwAugendRegister != 0); + + while (0 == (m_dwAugendRegister & 0x8000)) + { + int nNextBit = GetABit(); + if (1 == nNextBit) + { + if ((++m_nPostBitCount) >= 256) + return -1; + nNextBit = 0 ; + } + m_dwCodeRegister = (m_dwCodeRegister << 1) | ((uint)nNextBit & 1); + m_dwAugendRegister <<= 1; + } + m_dwCodeRegister &= 0xFFFF; + return iSym; + } + } + + internal class ErisaProbModel + { + public const int TotalLimit = 0x2000; + public const int SymbolSortMax = 0x101; + public const int SubSortMax = 0x80; + public const int ProbSlotMax = 0x800; + public const short EscCode = -1; + + internal struct CodeSymbol + { + public ushort Occured; + public short Symbol; + } + + public uint TotalCount; + public int SymbolSorts; + public CodeSymbol[] SymTable = new CodeSymbol[SymbolSortMax]; + public CodeSymbol[] SubModel = new CodeSymbol[SubSortMax]; + + public void Initialize () + { + TotalCount = SymbolSortMax; + SymbolSorts = SymbolSortMax; + + for (short i = 0; i < 0x100; ++i) + { + SymTable[i].Occured = 1; + SymTable[i].Symbol = i; + } + SymTable[0x100].Occured = 1 ; + SymTable[0x100].Symbol = EscCode; + + for (short i = 0; i < SubSortMax; ++i) + { + SubModel[i].Occured = 0; + SubModel[i].Symbol = -1; + } + } + + public int AccumulateProb (short wSymbol) + { + int index = FindSymbol (wSymbol); + Debug.Assert (index >= 0); + int occured = SymTable[index].Occured; + int i = 0; + while (occured < TotalCount) + { + occured <<= 1; + i++; + } + return i; + } + + public void HalfOccuredCount () + { + TotalCount = 0; + for (int i = 0; i < SymbolSorts; ++i) + { + TotalCount += SymTable[i].Occured = (ushort)((SymTable[i].Occured + 1) >> 1); + } + for (int i = 0; i < SubSortMax; ++i) + { + SubModel[i].Occured >>= 1 ; + } + } + + public int IncreaseSymbol (int index) + { + ushort occured = ++SymTable[index].Occured; + short symbol = SymTable[index].Symbol; + + while (--index >= 0) + { + if (SymTable[index].Occured >= occured) + break; + SymTable[index + 1] = SymTable[index]; + } + SymTable[++index].Occured = occured; + SymTable[index].Symbol = symbol; + + if (++TotalCount >= TotalLimit) + { + HalfOccuredCount(); + } + return index; + } + + public int FindSymbol (short symbol) + { + for (int index = 0; index < SymbolSorts; ++index) + { + if (SymTable[index].Symbol == symbol) + return index; + } + return -1; + } + + public int AddSymbol (short symbol) + { + int index = SymbolSorts++; + TotalCount++; + SymTable[index].Symbol = symbol; + SymTable[index].Occured = 1; + return index; + } + } }