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C# (previous one as well): re-implemented the LZ-0x11 algorithm in the new structure. Also updated the GBATEK-like format description of the format, hopefully correct this time.

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This commit is contained in:
barubary 2011-03-22 11:31:48 +00:00
parent 8c777e2c02
commit 1bd750c76d
3 changed files with 193 additions and 16 deletions
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10
CSharp/DSDecmp/Formats/Nitro/LZ10.cs
View File

@ -16,6 +16,7 @@ namespace DSDecmp.Formats.Nitro
public override void Decompress(Stream instream, long inLength,
Stream outstream)
{
#region format definition form GBATEK/NDSTEK
/* Data header (32bit)
Bit 0-3 Reserved
Bit 4-7 Compressed type (must be 1 for LZ77)
@ -30,6 +31,7 @@ namespace DSDecmp.Formats.Nitro
Bit 4-7 Number of bytes to copy (minus 3)
Bit 8-15 Disp LSBs
*/
#endregion
long readBytes = 0;
@ -49,7 +51,7 @@ namespace DSDecmp.Formats.Nitro
readBytes += 4;
}
// the maximum 'DISP' is 0xFFF.
// the maximum 'DISP-1' is 0xFFF.
int bufferLength = 0x1000;
byte[] buffer = new byte[bufferLength];
int bufferOffset = 0;
@ -61,7 +63,7 @@ namespace DSDecmp.Formats.Nitro
{
// (throws when requested new flags byte is not available)
#region Update the mask. If all flag bits have been read, get a new set.
// the current mask is the mask used in the previous run. So of it masks the
// the current mask is the mask used in the previous run. So if it masks the
// last flag bit, get a new flags byte.
if (mask == 1)
{
@ -88,7 +90,9 @@ namespace DSDecmp.Formats.Nitro
{
// make sure the stream is at the end
if (readBytes < inLength)
instream.ReadByte();
{
instream.ReadByte(); readBytes++;
}
throw new NotEnoughDataException(currentOutSize, decompressedSize);
}
int byte1 = instream.ReadByte(); readBytes++;

181
CSharp/DSDecmp/Formats/Nitro/LZ11.cs
View File

@ -11,6 +11,7 @@ namespace DSDecmp.Formats.Nitro
public override void Decompress(Stream instream, long inLength, Stream outstream)
{
#region Format definition in NDSTEK style
/* Data header (32bit)
Bit 0-3 Reserved
Bit 4-7 Compressed type (must be 1 for LZ77)
@ -31,16 +32,182 @@ namespace DSDecmp.Formats.Nitro
Bit 0-3 Disp MSBs
Bit 4-7 LEN - 1 (same bits as Indicator)
Bit 8-15 Disp LSBs
If Indicator is 1:
Bit 0-3 and 8-19 LEN - 0x111
Bit 20-31 Disp
If Indicator is 1: A(B CD E)(F GH)
Bit 0-3 (LEN - 0x111) MSBs
Bit 4-7 Indicator; unused
Bit 8-15 (LEN- 0x111) 'middle'-SBs
Bit 16-19 Disp MSBs
Bit 20-23 (LEN - 0x111) LSBs
Bit 24-31 Disp LSBs
If Indicator is 0:
Bit 0-3 and 8-11 LEN - 0x11
Bit 12-23 Disp
Bit 0-3 (LEN - 0x11) MSBs
Bit 4-7 Indicator; unused
Bit 8-11 Disp MSBs
Bit 12-15 (LEN - 0x11) LSBs
Bit 16-23 Disp LSBs
*/
#endregion
throw new NotImplementedException();
long readBytes = 0;
byte type = (byte)instream.ReadByte();
if (type != base.magicByte)
throw new InvalidDataException("The provided stream is not a valid LZ-0x11 "
+ "compressed stream (invalid type 0x" + type.ToString("X") + ")");
byte[] sizeBytes = new byte[3];
instream.Read(sizeBytes, 0, 3);
int decompressedSize = base.Bytes2Size(sizeBytes);
readBytes += 4;
if (decompressedSize == 0)
{
sizeBytes = new byte[4];
instream.Read(sizeBytes, 0, 4);
decompressedSize = base.Bytes2Size(sizeBytes);
readBytes += 4;
}
// the maximum 'DISP-1' is still 0xFFF.
int bufferLength = 0x1000;
byte[] buffer = new byte[bufferLength];
int bufferOffset = 0;
int currentOutSize = 0;
int flags = 0, mask = 0;
while (currentOutSize < decompressedSize)
{
// (throws when requested new flags byte is not available)
#region Update the mask. If all flag bits have been read, get a new set.
// the current mask is the mask used in the previous run. So if it masks the
// last flag bit, get a new flags byte.
if (mask == 1)
{
if (readBytes >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
flags = instream.ReadByte(); readBytes++;
if (flags < 0)
throw new StreamTooShortException();
mask = 0x80;
}
else
{
mask >>= 1;
}
#endregion
// bit = 1 <=> compressed.
if ((flags & mask) > 0)
{
// (throws when not enough bytes are available)
#region Get length and displacement('disp') values from next 2, 3 or 4 bytes
// read the first byte first, which also signals the size of the compressed block
if (readBytes >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
int byte1 = instream.ReadByte(); readBytes++;
if (byte1 < 0)
throw new StreamTooShortException();
int length = byte1 >> 4;
int disp = -1;
if (length == 0)
{
#region case 0; (0B C)(D EF) + (0x11)(0x1) = (LEN)(DISP)
// case 0:
// data = AB CD EF (with A=0)
// LEN = ABC + 0x11 == BC + 0x11
// DISP = DEF + 1
// we need two more bytes available
if (readBytes + 1 >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
int byte2 = instream.ReadByte(); readBytes++;
int byte3 = instream.ReadByte(); readBytes++;
if (byte3 < 0)
throw new StreamTooShortException();
length = (((byte1 & 0x0F) << 4) | (byte2 >> 4)) + 0x11;
disp = (((byte2 & 0x0F) << 8) | byte3) + 0x1;
#endregion
}
else if (length == 1)
{
#region case 1: 1(B CD E)(F GH) + (0x111)(0x1) = (LEN)(DISP)
// case 1:
// data = AB CD EF GH (with A=1)
// LEN = BCDE + 0x111
// DISP = FGH + 1
// we need three more bytes available
if (readBytes + 2 >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
int byte2 = instream.ReadByte(); readBytes++;
int byte3 = instream.ReadByte(); readBytes++;
int byte4 = instream.ReadByte(); readBytes++;
if (byte4 < 0)
throw new StreamTooShortException();
length = (((byte1 & 0x0F) << 12) | (byte2 << 4) | (byte3 >> 4)) + 0x111;
disp = (((byte3 & 0x0F) << 8) | byte4) + 0x1;
#endregion
}
else
{
#region case > 1: (A)(B CD) + (0x1)(0x1) = (LEN)(DISP)
// case other:
// data = AB CD
// LEN = A + 1
// DISP = BCD + 1
// we need only one more byte available
if (readBytes >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
int byte2 = instream.ReadByte(); readBytes++;
if (byte2 < 0)
throw new StreamTooShortException();
length = ((byte1 & 0xF0) >> 4) + 0x1;
disp = (((byte1 & 0x0F) << 8) | byte2) + 0x1;
#endregion
}
if (disp > currentOutSize)
throw new InvalidDataException("Cannot go back more than already written. "
+ "DISP = " + disp + ", #written bytes = 0x" + currentOutSize.ToString("X")
+ " before 0x" + instream.Position.ToString("X") + " with indicator 0x"
+ (byte1 >> 4).ToString("X"));
#endregion
int bufIdx = bufferOffset + bufferLength - disp;
for (int i = 0; i < length; i++)
{
byte next = buffer[bufIdx % bufferLength];
bufIdx++;
outstream.WriteByte(next);
buffer[bufferOffset] = next;
bufferOffset = (bufferOffset + 1) % bufferLength;
}
}
else
{
if (readBytes >= inLength)
throw new NotEnoughDataException(currentOutSize, decompressedSize);
int next = instream.ReadByte(); readBytes++;
if (next < 0)
throw new StreamTooShortException();
currentOutSize++;
outstream.WriteByte((byte)next);
buffer[bufferOffset] = (byte)next;
bufferOffset = (bufferOffset + 1) % bufferLength;
}
}
}
public override void Compress(Stream instream, long inLength, Stream outstream)

18
CSharp/DSDecmp/Program.cs
View File

@ -781,13 +781,19 @@ namespace DSDecmp
Bit 0-3 Disp MSBs
Bit 4-7 LEN - 1 (same bits as Indicator)
Bit 8-15 Disp LSBs
If Indicator is 1:
Bit 0-3 and 8-19 LEN - 0x111
Bit 20-31 Disp
If Indicator is 1: A(B CD E)(F GH)
Bit 0-3 (LEN - 0x111) MSBs
Bit 4-7 Indicator; unused
Bit 8-15 (LEN- 0x111) 'middle'-SBs
Bit 16-19 Disp MSBs
Bit 20-23 (LEN - 0x111) LSBs
Bit 24-31 Disp LSBs
If Indicator is 0:
Bit 0-3 and 8-11 LEN - 0x11
Bit 12-23 Disp
Bit 0-3 (LEN - 0x11) MSBs
Bit 4-7 Indicator; unused
Bit 8-11 Disp MSBs
Bit 12-15 (LEN - 0x11) LSBs
Bit 16-23 Disp LSBs
*/
FileStream fstr = new FileStream(filein, FileMode.Open);
if (fstr.Length > int.MaxValue)