mirror of
https://github.com/claunia/cuetools.net.git
synced 2025-12-16 18:14:25 +00:00
676 lines
19 KiB
C#
676 lines
19 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Text;
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using CUETools.Codecs;
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using CUETools.Parity;
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namespace CUETools.CDRepair
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{
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public class CDRepair : IAudioDest
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{
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protected int sampleCount;
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protected int finalSampleCount;
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protected Galois galois;
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protected RsDecode rs;
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protected Crc32 crc32;
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protected uint crc;
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protected int[] encodeGx;
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protected int stride;
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protected int laststride;
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protected int stridecount;
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protected int npar;
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public CDRepair(int finalSampleCount, int stride, int npar)
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{
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this.npar = npar;
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this.stride = stride;
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this.finalSampleCount = finalSampleCount;
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sampleCount = 0;
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galois = Galois16.instance;
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rs = new RsDecode16(npar, galois);
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crc32 = new Crc32();
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//crc = 0xffffffff;
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encodeGx = galois.makeEncodeGxLog(npar);
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laststride = stride + (finalSampleCount * 2) % stride;
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stridecount = (finalSampleCount * 2) / stride - 2; // minus one for leadin and one for leadout
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if ((finalSampleCount * 2 + stride - 1) / stride + npar > galois.Max)
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throw new Exception("invalid stride");
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}
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public CDRepair(CDRepair src)
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: this(src.finalSampleCount, src.stride, src.npar)
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{
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}
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public unsafe void Write(AudioBuffer sampleBuffer)
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{
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throw new Exception("unsupported");
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}
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public unsafe void Close()
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{
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if (sampleCount != finalSampleCount)
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throw new Exception("sampleCount != finalSampleCount");
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}
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public void Delete()
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{
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throw new Exception("unsupported");
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}
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public int CompressionLevel
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{
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get { return 0; }
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set { }
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}
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public string Options
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{
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set
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{
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if (value == null || value == "") return;
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throw new Exception("Unsupported options " + value);
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}
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}
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public AudioPCMConfig PCM
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{
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get { return AudioPCMConfig.RedBook; }
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}
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public long FinalSampleCount
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{
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set
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{
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if (value < 0) // != _toc.Length?
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throw new Exception("invalid FinalSampleCount");
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finalSampleCount = (int)value;
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}
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}
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public long BlockSize
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{
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set { throw new Exception("unsupported"); }
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}
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public string Path
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{
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get { throw new Exception("unsupported"); }
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}
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public int NPAR
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{
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get
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{
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return npar;
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}
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}
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public uint CRC
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{
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get
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{
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return crc32.Combine(0xffffffff, crc, stride * 2 * stridecount) ^ 0xffffffff;
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}
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}
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}
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public class CDRepairEncode : CDRepair
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{
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protected byte[] parity;
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protected ushort[,] syndrome;
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protected ushort[] leadin;
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protected ushort[] leadout;
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protected bool verify;
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protected bool encode;
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protected uint crcA, crcB;
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public CDRepairEncode(int finalSampleCount, int stride, int npar, bool verify, bool encode)
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: base (finalSampleCount, stride, npar)
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{
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this.verify = verify;
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this.encode = encode;
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parity = new byte[stride * npar * 2];
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if (verify)
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{
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syndrome = new ushort[stride, npar];
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leadin = new ushort[stride * 2];
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leadout = new ushort[stride + laststride];
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} else
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syndrome = new ushort[1, npar];
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}
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private unsafe void ProcessStride(int currentStride, int currentPart, int count, ushort* data)
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{
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fixed (uint* crct = crc32.table)
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fixed (byte* bpar = parity)
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fixed (ushort* exp = galois.ExpTbl, log = galois.LogTbl, synptr = syndrome)
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fixed (int* gx = encodeGx)
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for (int pos = 0; pos < count; pos++)
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{
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ushort* par = (ushort*)bpar;
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int part = currentPart + pos;
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ushort* wr = ((ushort*)par) + part * npar;
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ushort dd = data[pos];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ dd)];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ (dd >> 8))];
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if (verify)
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{
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ushort* syn = synptr + part * npar;
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syn[0] ^= dd; // wk += data
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for (int i = 1; i < npar; i++)
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syn[i] = (ushort)(dd ^ galois.mulExp(syn[i], i)); // wk = data + wk * α^i
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}
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int ib = wr[0] ^ dd;
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if (ib != 0)
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{
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ushort* myexp = exp + log[ib];
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for (int i = 0; i < npar - 1; i++)
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wr[i] = (ushort)(wr[i + 1] ^ myexp[gx[i]]);
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wr[npar - 1] = myexp[gx[npar - 1]];
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}
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else
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{
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for (int i = 0; i < npar - 1; i++)
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wr[i] = wr[i + 1];
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wr[npar - 1] = 0;
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}
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}
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}
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private unsafe void ProcessStride8(int currentStride, int currentPart, int count, ushort* data)
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{
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fixed (uint* crct = crc32.table)
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fixed (byte* bpar = parity)
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fixed (ushort* exp = galois.ExpTbl, log = galois.LogTbl, synptr = syndrome)
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for (int pos = 0; pos < count; pos++)
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{
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ushort* par = (ushort*)bpar;
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int part = currentPart + pos;
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ushort* wr = par + part * 8;
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ushort dd = data[pos];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ dd)];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ (dd >> 8))];
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if (encode)
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{
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int ib = wr[0] ^ dd;
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if (ib != 0)
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{
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ushort* myexp = exp + log[ib];
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wr[0] = (ushort)(wr[1] ^ myexp[19483]);
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wr[1] = (ushort)(wr[2] ^ myexp[41576]);
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wr[2] = (ushort)(wr[3] ^ myexp[9460]);
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wr[3] = (ushort)(wr[4] ^ myexp[52075]);
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wr[4] = (ushort)(wr[5] ^ myexp[9467]);
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wr[5] = (ushort)(wr[6] ^ myexp[41590]);
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wr[6] = (ushort)(wr[7] ^ myexp[19504]);
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wr[7] = myexp[28];
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}
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else
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{
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wr[0] = wr[1];
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wr[1] = wr[2];
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wr[2] = wr[3];
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wr[3] = wr[4];
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wr[4] = wr[5];
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wr[5] = wr[6];
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wr[6] = wr[7];
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wr[7] = 0;
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}
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}
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// syn[i] += data[pos] * α^(n*i)
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if (verify && dd != 0)
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{
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int n = stridecount - currentStride;
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ushort* syn = synptr + part * 8;
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syn[0] ^= dd;
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int idx = log[dd];
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idx += n; syn[1] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[2] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[3] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[4] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[5] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[6] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[7] ^= exp[(idx & 0xffff) + (idx >> 16)];
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}
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}
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}
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private unsafe void ProcessStride16(int currentStride, int currentPart, int count, ushort* data)
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{
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fixed (uint* crct = crc32.table)
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fixed (byte* bpar = parity)
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fixed (ushort* exp = galois.ExpTbl, log = galois.LogTbl, synptr = syndrome)
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for (int pos = 0; pos < count; pos++)
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{
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ushort* par = (ushort*)bpar;
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int part = currentPart + pos;
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ushort* wr = par + part * 16;
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ushort dd = data[pos];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ dd)];
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crc = (crc >> 8) ^ crct[(byte)(crc ^ (dd >> 8))];
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int ib = wr[0] ^ dd;
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if (ib != 0)
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{
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ushort* myexp = exp + log[ib];
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wr[0] = (ushort)(wr[1] ^ myexp[0x000059f1]);
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wr[1] = (ushort)(wr[2] ^ myexp[0x0000608f]);
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wr[2] = (ushort)(wr[3] ^ myexp[0x0000918b]);
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wr[3] = (ushort)(wr[4] ^ myexp[0x00004487]);
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wr[4] = (ushort)(wr[5] ^ myexp[0x0000a151]);
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wr[5] = (ushort)(wr[6] ^ myexp[0x0000c074]);
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wr[6] = (ushort)(wr[7] ^ myexp[0x00004178]);
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wr[7] = (ushort)(wr[8] ^ myexp[0x00004730]);
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wr[8] = (ushort)(wr[9] ^ myexp[0x00004187]);
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wr[9] = (ushort)(wr[10] ^ myexp[0x0000c092]);
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wr[10] = (ushort)(wr[11] ^ myexp[0x0000a17e]);
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wr[11] = (ushort)(wr[12] ^ myexp[0x000044c3]);
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wr[12] = (ushort)(wr[13] ^ myexp[0x000091d6]);
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wr[13] = (ushort)(wr[14] ^ myexp[0x000060e9]);
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wr[14] = (ushort)(wr[15] ^ myexp[0x00005a5a]);
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wr[15] = myexp[0x00000078];
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}
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else
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{
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wr[0] = wr[1];
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wr[1] = wr[2];
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wr[2] = wr[3];
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wr[3] = wr[4];
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wr[4] = wr[5];
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wr[5] = wr[6];
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wr[6] = wr[7];
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wr[7] = wr[8];
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wr[8] = wr[9];
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wr[9] = wr[10];
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wr[10] = wr[11];
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wr[11] = wr[12];
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wr[12] = wr[13];
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wr[13] = wr[14];
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wr[14] = wr[15];
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wr[15] = 0;
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}
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// syn[i] += data[pos] * α^(n*i)
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if (verify && dd != 0)
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{
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int n = stridecount - currentStride;
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ushort* syn = synptr + part * 16;
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syn[0] ^= dd;
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int idx = log[dd];
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idx += n; syn[1] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[2] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[3] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[4] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[5] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[6] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[7] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[8] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[9] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[10] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[11] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[12] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[13] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[14] ^= exp[(idx & 0xffff) + (idx >> 16)];
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idx += n; syn[15] ^= exp[(idx & 0xffff) + (idx >> 16)];
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}
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}
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}
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new public unsafe void Write(AudioBuffer sampleBuffer)
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{
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sampleBuffer.Prepare(this);
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if ((sampleBuffer.ByteLength & 1) != 0)
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throw new Exception("never happens");
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fixed (byte* bytes = sampleBuffer.Bytes)
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{
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int offs = 0;
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while (offs < sampleBuffer.Length)
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{
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int currentPart = (sampleCount * 2) % stride;
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int currentStride = (sampleCount * 2) / stride;
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// Process no more than there is in the buffer, and no more than up to a stride boundary.
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int copyCount = Math.Min((sampleBuffer.Length - offs) * 2, stride - currentPart);
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ushort* data = ((ushort*)bytes) + offs * 2;
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if (verify)
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{
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// remember CRC after leadin
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if (sampleCount * 2 == stride * 2)
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crcA = crc;
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// remember CRC before leadout
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if ((finalSampleCount - sampleCount) * 2 == stride + laststride)
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crcB = crc;
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if (currentStride < 2)
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for (int pos = 0; pos < copyCount; pos++)
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leadin[sampleCount * 2 + pos] = data[pos];
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if (currentStride >= stridecount)
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for (int pos = 0; pos < copyCount; pos++)
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{
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int remaining = (finalSampleCount - sampleCount) * 2 - pos - 1;
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if (remaining < stride + laststride)
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leadout[remaining] = data[pos];
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}
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}
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if (currentStride >= 1 && currentStride <= stridecount)
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{
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if (npar == 8)
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ProcessStride8(currentStride, currentPart, copyCount, data);
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else if (npar == 16)
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ProcessStride16(currentStride, currentPart, copyCount, data);
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else
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ProcessStride(currentStride, currentPart, copyCount, data);
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}
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sampleCount += copyCount >> 1;
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offs += copyCount >> 1;
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}
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}
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}
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public unsafe CDRepairFix VerifyParity(byte[] parity2, int actualOffset)
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{
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return VerifyParity(npar, parity2, 0, parity2.Length, actualOffset);
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}
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private unsafe uint OffsettedCRC(int actualOffset)
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{
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fixed (uint* crct = crc32.table)
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{
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// calculate leadin CRC
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uint crc0 = 0;
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for (int off = stride - 2 * actualOffset; off < 2 * stride; off++)
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{
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ushort dd = leadin[off];
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crc0 = (crc0 >> 8) ^ crct[(byte)(crc0 ^ dd)];
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crc0 = (crc0 >> 8) ^ crct[(byte)(crc0 ^ (dd >> 8))];
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}
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// calculate leadout CRC
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uint crc2 = 0;
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for (int off = laststride + stride - 1; off >= laststride + 2 * actualOffset; off--)
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{
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ushort dd = leadout[off];
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crc2 = (crc2 >> 8) ^ crct[(byte)(crc2 ^ dd)];
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crc2 = (crc2 >> 8) ^ crct[(byte)(crc2 ^ (dd >> 8))];
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}
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// calculate middle CRC
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uint crc1 = crc32.Combine(crcA, crcB, (stridecount - 2) * stride * 2);
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// calculate offsettedCRC as sum of 0xffffffff, crc0, crc1, crc2;
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return crc32.Combine(
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0xffffffff,
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crc32.Combine(
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crc32.Combine(
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crc0,
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crc1,
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(stridecount - 2) * stride * 2),
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crc2,
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(stride - 2 * actualOffset) * 2),
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stridecount * stride * 2) ^ 0xffffffff;
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}
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}
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public unsafe bool FindOffset(int npar2, byte[] parity2, int pos, uint expectedCRC, out int actualOffset, out bool hasErrors)
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{
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if (npar2 != npar)
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throw new Exception("npar mismatch");
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if (!verify)
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throw new Exception("verify was not enabled");
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if (sampleCount != finalSampleCount)
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throw new Exception("sampleCount != finalSampleCount");
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// find offset
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fixed (byte* par2ptr = &parity2[pos])
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{
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ushort* par2 = (ushort*)par2ptr;
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int* _sigma = stackalloc int[npar];
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int* _errpos = stackalloc int[npar];
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int* syn = stackalloc int[npar];
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bool foundOffset = false;
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for (int allowed_errors = 0; allowed_errors < npar / 2 && !foundOffset; allowed_errors++)
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{
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int part2 = 0;
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ushort* wr = par2 + part2 * npar;
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// We can only use offset if Abs(offset * 2) < stride,
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// else we might need to add/remove more than one sample
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// from syndrome calculations, and that would be too difficult
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// and will probably require longer leadin/leadout.
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for (int offset = 1 - stride / 2; offset < stride / 2; offset++)
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{
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int err = 0;
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int part = (part2 + stride - offset * 2) % stride;
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for (int i = 0; i < npar; i++)
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{
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int synI = syndrome[part, i];
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// offset < 0
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if (part < -offset * 2)
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{
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synI ^= galois.mulExp(leadin[stride + part], (i * (stridecount - 1)) % galois.Max);
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synI = leadout[laststride - part - 1] ^ galois.mulExp(synI, i);
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}
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// offset > 0
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if (part >= stride - offset * 2)
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{
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synI = galois.divExp(synI ^ leadout[laststride + stride - part - 1], i);
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synI ^= galois.mulExp(leadin[part], (i * (stridecount - 1)) % galois.Max);
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}
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for (int j = 0; j < npar; j++)
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synI = wr[j] ^ galois.mulExp(synI, i);
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syn[i] = synI;
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err |= synI;
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}
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int err_count = err == 0 ? 0 : rs.calcSigmaMBM(_sigma, syn);
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if (err_count == allowed_errors && (err_count == 0 || rs.chienSearch(_errpos, stridecount + npar, err_count, _sigma)))
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{
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actualOffset = offset;
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hasErrors = err_count != 0 || OffsettedCRC(offset) != expectedCRC;
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return true;
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||
}
|
||
}
|
||
}
|
||
}
|
||
actualOffset = 0;
|
||
hasErrors = true;
|
||
return false;
|
||
}
|
||
|
||
public unsafe CDRepairFix VerifyParity(int npar2, byte[] parity2, int pos, int len, int actualOffset)
|
||
{
|
||
if (len != stride * npar * 2)
|
||
throw new Exception("wrong size");
|
||
|
||
CDRepairFix fix = new CDRepairFix(this);
|
||
fix.actualOffset = actualOffset;
|
||
fix.correctableErrors = 0;
|
||
fix.hasErrors = false;
|
||
fix.canRecover = true;
|
||
|
||
fix.sigma = new int[stride, npar / 2 + 2];
|
||
fix.omega = new int[stride, npar / 2 + 1];
|
||
fix.errpos = new int[stride, npar / 2];
|
||
fix.erroff = new int[stride, npar / 2];
|
||
fix.errors = new int[stride];
|
||
|
||
fixed (byte* par = &parity2[pos])
|
||
fixed (ushort* exp = galois.ExpTbl, log = galois.LogTbl)
|
||
{
|
||
int* syn = stackalloc int[npar];
|
||
int offset = fix.actualOffset;
|
||
|
||
for (int part = 0; part < stride; part++)
|
||
{
|
||
int part2 = (part + offset * 2 + stride) % stride;
|
||
ushort* wr = (ushort*)par + part2 * npar;
|
||
int err = 0;
|
||
|
||
for (int i = 0; i < npar; i++)
|
||
{
|
||
syn[i] = syndrome[part, i];
|
||
|
||
// offset < 0
|
||
if (part < -offset * 2)
|
||
{
|
||
syn[i] ^= galois.mulExp(leadin[stride + part], (i * (stridecount - 1)) % galois.Max);
|
||
syn[i] = leadout[laststride - part - 1] ^ galois.mulExp(syn[i], i);
|
||
}
|
||
// offset > 0
|
||
if (part >= stride - offset * 2)
|
||
{
|
||
syn[i] = galois.divExp(syn[i] ^ leadout[laststride + stride - part - 1], i);
|
||
syn[i] ^= galois.mulExp(leadin[part], (i * (stridecount - 1)) % galois.Max);
|
||
}
|
||
|
||
//syn[i] = galois.mulExp(syn[i], i * npar);
|
||
|
||
for (int j = 0; j < npar; j++)
|
||
syn[i] = wr[j] ^ galois.mulExp(syn[i], i); // wk = data + wk * α^i
|
||
|
||
err |= syn[i];
|
||
}
|
||
|
||
//for (int j = 0; j < npar; j++)
|
||
// if (wr[j] != 0)
|
||
// {
|
||
// ushort* myexp = exp + log[wr[j]];
|
||
// syn[0] ^= wr[j];
|
||
// for (int i = 1; i < npar; i++)
|
||
// syn[i] ^= myexp[(npar - j - 1) * i];
|
||
// }
|
||
|
||
//for (int i = 0; i < npar; i++)
|
||
// err |= syn[i];
|
||
|
||
if (err != 0)
|
||
{
|
||
fixed (int* s = &fix.sigma[part, 0], o = &fix.omega[part, 0], e = &fix.errpos[part, 0], f = &fix.erroff[part, 0])
|
||
{
|
||
fix.errors[part] = rs.calcSigmaMBM(s, syn);
|
||
fix.hasErrors = true;
|
||
fix.correctableErrors += fix.errors[part];
|
||
if (fix.errors[part] <= 0 || !rs.chienSearch(e, stridecount + npar, fix.errors[part], s))
|
||
fix.canRecover = false;
|
||
else
|
||
{
|
||
galois.mulPoly(o, s, syn, npar / 2 + 1, npar, npar);
|
||
for (int i = 0; i < fix.errors[part]; i++)
|
||
f[i] = galois.toPos(stridecount + npar, e[i]);
|
||
}
|
||
}
|
||
}
|
||
else
|
||
fix.errors[part] = 0;
|
||
}
|
||
}
|
||
|
||
return fix;
|
||
}
|
||
|
||
public byte[] Parity
|
||
{
|
||
get
|
||
{
|
||
return parity;
|
||
}
|
||
}
|
||
}
|
||
|
||
public class CDRepairFix : CDRepair
|
||
{
|
||
internal bool hasErrors = false, canRecover = true;
|
||
internal int actualOffset = 0;
|
||
internal int correctableErrors = 0;
|
||
internal int[,] sigma;
|
||
internal int[,] omega;
|
||
internal int[,] errpos;
|
||
internal int[,] erroff;
|
||
internal int[] errors;
|
||
|
||
public CDRepairFix(CDRepairEncode decode)
|
||
: base(decode)
|
||
{
|
||
}
|
||
|
||
new public unsafe void Write(AudioBuffer sampleBuffer)
|
||
{
|
||
sampleBuffer.Prepare(this);
|
||
|
||
if ((sampleBuffer.ByteLength & 1) != 0)
|
||
throw new Exception("never happens");
|
||
|
||
int firstPos = Math.Max(0, stride - sampleCount * 2 - ActualOffset * 2);
|
||
int lastPos = Math.Min(sampleBuffer.ByteLength >> 1, (finalSampleCount - sampleCount) * 2 - laststride - ActualOffset * 2);
|
||
|
||
fixed (byte* bytes = sampleBuffer.Bytes)
|
||
fixed (uint* t = crc32.table)
|
||
{
|
||
ushort* data = (ushort*)bytes;
|
||
for (int pos = firstPos; pos < lastPos; pos++)
|
||
{
|
||
int part = (sampleCount * 2 + pos) % stride;
|
||
int nerrors = errors[part];
|
||
fixed (int* s = &sigma[part, 0], o = &omega[part, 0], f = &erroff[part, 0])
|
||
for (int i = 0; i < nerrors; i++)
|
||
if (f[i] == (sampleCount * 2 + ActualOffset * 2 + pos) / stride - 1)
|
||
data[pos] ^= (ushort)rs.doForney(nerrors, errpos[part, i], s, o);
|
||
|
||
ushort dd = data[pos];
|
||
|
||
crc = (crc >> 8) ^ t[(byte)(crc ^ dd)];
|
||
crc = (crc >> 8) ^ t[(byte)(crc ^ (dd >> 8))];
|
||
}
|
||
}
|
||
sampleCount += sampleBuffer.Length;
|
||
}
|
||
|
||
public bool HasErrors
|
||
{
|
||
get
|
||
{
|
||
return hasErrors;
|
||
}
|
||
}
|
||
|
||
public bool CanRecover
|
||
{
|
||
get
|
||
{
|
||
return canRecover;
|
||
}
|
||
}
|
||
|
||
public int CorrectableErrors
|
||
{
|
||
get
|
||
{
|
||
return correctableErrors;
|
||
}
|
||
}
|
||
|
||
public int ActualOffset
|
||
{
|
||
get
|
||
{
|
||
return actualOffset;
|
||
}
|
||
}
|
||
}
|
||
}
|