public PrcImages(Header header, PDBheader pdb)
{
m_FirstImageRec = header.ReadInt(108);
// First image rec: Bytes 108-4 big-endian integer
if (m_FirstImageRec > 0)
{
m_ImageArray = new ArrayList();
// Loop though images. Ignore last two records (FLIS and FCIS)
for (int i = m_FirstImageRec; i < pdb.RecordCnt - 3; i++)
{
Image newImage;
// get the next image
Byte[] imageRec = pdb.GetRecord(i);
// Check for various image formats (JPG,GIF,BMP etc)
String jpgFlag = ReadString(imageRec, 6, 4);
if (jpgFlag.Equals("JFIF"))
{
newImage = LoadJPEG(imageRec);
m_ImageArray.Add(newImage);
}
String gifFlag = ReadString(imageRec, 0, 3);
if (gifFlag.Equals("GIF"))
{
newImage = LoadGIF(imageRec);
m_ImageArray.Add(newImage);
}
}
}
}
public PRCheader(Header header)
{
// Compression : Bytes 0-2 big-endian integer
m_Compression = header.ReadShort(0);
// Uncompressed Text Length: Bytes 4-4 big-endian integer
m_UncompTextLen = header.ReadInt(4);
m_UncompTextLen += 2; // allow for trailing CRLF
// record Count : Bytes 8-2 big-endian integer
m_PRCrecCnt = header.ReadShort(8);
// Max record lenth : Bytes 10-2 big-endian integer
m_MaxRecLen = header.ReadShort(10);
// Encryption : Bytes 12-2 big-endian integer
m_Encryption = header.ReadShort(12);
}
//private byte[] m_Array;
public PDBheader(Header header)
{
int temp;
if (header.Length < 80)
throw new Exception("PDB header is too small");
m_Array = header;
// Filename. Bytes 0-32 null terminated ASCII
m_Filename = m_Array.ReadString(0, 32);
m_Filename = m_Filename.Substring(0, m_Filename.IndexOf('\0'));
// Version - Bytes 34-2 high-endian integer;
m_Version = m_Array.ReadShort(34);
// Creation date - Bytes 36-4 high-endian integer. Despite the comments
// above, the time is based on 1-Jan-1970 not 1-Jan-1904
temp = m_Array.ReadInt(36);
m_CreationDate = new DateTime(1970, 1, 1, 0, 0, 0);
m_CreationDate = m_CreationDate.AddSeconds((double)temp);
// Modification date - Bytes 40-4 high-endian integer. Despite the comments
// above, the time is based on 1-Jan-1970 not 1-Jan-1904
temp = m_Array.ReadInt(40);
m_ModificationDate = new DateTime(1970, 1, 1, 0, 0, 0);
m_ModificationDate = m_ModificationDate.AddSeconds((double)temp);
// Type - Bytes 60-4 ASCII
m_Type = m_Array.ReadString(60, 4);
// Creator - Bytes 64-4 ASCII
m_Creator = m_Array.ReadString(64, 4);
// Record count - Bytes 76-2 high-endian integer;
m_RecordCnt = m_Array.ReadShort(76);
// Build a list of pointers to records. These are held in an array
// starting in bytes 78-8.
m_RecPointer = new ArrayList(m_RecordCnt);
for (int i = 0; i < m_RecordCnt; i++)
{
int offs = 78 + (i * 8);
temp = m_Array.ReadInt(offs);
m_RecPointer.Add(temp);
}
}
private void LoadPRC(string fn)
{
m_File = new FileStream(fn, FileMode.Open, FileAccess.Read);
m_Array = new Byte[m_File.Length];
m_File.Read(m_Array, 0, m_Array.Length);
Header m_Header = new Header(m_Array);
m_PDBheader = new PDBheader(m_Header);
byte[] prcRec = m_PDBheader.GetRecord(0);
m_Rec0 = new Header(prcRec);
m_PRCheader = new PRCheader(m_Rec0);
m_MOBIheader = new MOBIheader(m_Rec0);
// Does an EXTH header exist? Byte 126 bit 6 (0x40)
bool m_EXTHexists = (((int)prcRec[126] & 0x40) == 0x00);
if (m_EXTHexists)
{
m_EXTHheader = new EXTHheader(m_Rec0);
}
// Images
m_Images = new PrcImages(m_Rec0, m_PDBheader);
}
public MOBIheader(Header header)
{
// MOBI eye catcher - Bytes 16-4 ASCII
m_MOBI = header.ReadString(16, 4);
if (!m_MOBI.Equals("MOBI"))
throw new Exception("Invalid PRC file (reason 01)");
// Header length, including eye catcher : Bytes 20-4 big-endian integer
m_MOBIlen = header.ReadInt(20);
// MOBI type : Bytes 24-4 big-endian integer
m_MOBItype = header.ReadInt(24);
// Encoding 1252=CP1252 65001=UTF-8 : Bytes 28-4 big-endian integer
m_Encoding = header.ReadInt(28);
// PRC version - mobipocket format : Bytes 36-4 big-endian integer
m_PrcVersion = header.ReadInt(36);
// Document Fullname: Offset into rec 0 at bytes 84-4 length 88-4
int fnOffset = header.ReadInt(84);
int fnLength = header.ReadInt(88);
m_Fullname = header.ReadString(fnOffset, fnLength);
// Locale : Bytes 92-4 big-endian integer
m_Locale = header.ReadInt(92);
// First image rec: Bytes 108-4 big-endian integer
m_FirstImageRec = header.ReadInt(108);
// First huffman rec: Bytes 112-4 big-endian integer
m_FirstHuffmanRec = header.ReadInt(112);
// Huffman rec count: Bytes 116-4 big-endian integer
m_HuffmanRecCnt = header.ReadInt(116);
// Huffman table offset: Bytes 120-4 big-endian integer
m_HuffmanTableOffset = header.ReadInt(120);
// Huffman table length: Bytes 124-4 big-endian integer
m_HuffmanTableLen = header.ReadInt(124);
}
public HuffmanDecompress(Header header)
: base()
{
}
public EXTHheader(Header header)
{
// Header length, including eye catcher : Bytes 20-4 big-endian integer
m_MOBIlen = header.ReadInt(20);
// EXTH follows immediately after MOBI
m_EXTHoffset = m_MOBIlen + 16;
// EXTH eye catcher - Bytes EXTH+0-4 ASCII
m_EXTH = header.ReadString(m_EXTHoffset, 4);
if (!m_EXTH.Equals("EXTH"))
throw new Exception("Invalid PRC file (reason 02)");
// Get the total length of the EXTH record
int totLen = header.ReadInt(m_EXTHoffset + 4);
// Get the count of EXTH records
int recCnt = header.ReadInt(m_EXTHoffset + 8);
// Loop through the rest of the EXTH records saving them
int endOffset = m_EXTHoffset + totLen;
int pos = m_EXTHoffset + 12;
while (pos < endOffset - 1)
{
String value;
int recType = header.ReadInt(pos);
int recLen = header.ReadInt(pos + 4);
switch (recType)
{
case 115:
case 116:
case 201:
case 202:
case 204:
case 205:
case 206:
case 207:
value = header.ReadInt(pos + 8).ToString();
break;
default:
value = header.ReadString(pos + 8, recLen - 8);
break;
}
m_EXTHrecs.Add(recType, value);
pos += recLen;
}
}
