//////////////////////////////////////////////////////////////////////////
// public methods
//////////////////////////////////////////////////////////////////////////
public OggPage(OggFile file, long pageOffset)
{
this.file = file;
this.fileOffset = pageOffset;
//packetOffset = 0;
//dataSize = 0;
header = new OggPageHeader(file, pageOffset);
firstPacketIndex = -1;
packets = new ByteVectorCollection();
if (file != null)
{
packetOffset = fileOffset + header.Size;
dataSize = header.DataSize;
}
}
//////////////////////////////////////////////////////////////////////////
// public methods
//////////////////////////////////////////////////////////////////////////
public OggPage(OggFile file, long pageOffset)
{
this.file = file;
this.fileOffset = pageOffset;
//packetOffset = 0;
//dataSize = 0;
header = new OggPageHeader(file, pageOffset);
firstPacketIndex = -1;
packets = new ByteVectorCollection();
if (file != null)
{
packetOffset = fileOffset + header.Size;
dataSize = header.DataSize;
}
}
public OggPageHeader(OggFile file, long pageOffset)
{
//isValid = false;
//packetSizes = new ArrayList();
//firstPacketContinued = false;
//lastPacketCompleted = false;
//first_page_of_stream = false;
//last_page_of_stream = false;
//absolute_granular_position = 0;
//streamSerialNumber = 0;
//pageSequenceNumber = -1;
//size = 0;
//data_size = 0;
if (file != null && pageOffset >= 0)
Read(file, pageOffset);
}
public OggPageHeader(OggFile file, long pageOffset)
{
//isValid = false;
//packetSizes = new ArrayList();
//firstPacketContinued = false;
//lastPacketCompleted = false;
//first_page_of_stream = false;
//last_page_of_stream = false;
//absolute_granular_position = 0;
//streamSerialNumber = 0;
//pageSequenceNumber = -1;
//size = 0;
//data_size = 0;
if (file != null && pageOffset >= 0)
{
Read(file, pageOffset);
}
}
private void Read(OggFile file, long file_offset)
{
file.Seek(file_offset);
// An Ogg page header is at least 27 buffer, so we'll go ahead and read that
// much and then get the rest when we're ready for it.
ByteVector data = file.ReadBlock(27);
// Sanity check -- make sure that we were in fact able to read as much data as
// we asked for and that the page begins with "OggS".
if (data.Count != 27 || !data.StartsWith("OggS"))
{
TagLibDebugger.Debug("Ogg.PageHeader.Read() -- error reading page header");
return;
}
byte flags = data[5];
firstPacketContinued = (flags & 1) != 0;
firstPageOfStream = ((flags >> 1) & 1) != 0;
lastPageOfStream = ((flags >> 2) & 1) != 0;
absoluteGranularPosition = data.Mid(6, 8).ToLong(false);
streamSerialNumber = data.Mid(14, 4).ToUInt(false);
pageSequenceNumber = (int)data.Mid(18, 4).ToUInt(false);
// Byte number 27 is the number of page segments, which is the only variable
// length portion of the page header. After reading the number of page
// segments we'll then read in the coresponding data for this count.
int pageSegmentCount = data[26];
ByteVector page_segments = file.ReadBlock(pageSegmentCount);
// Another sanity check.
if (pageSegmentCount < 1 || page_segments.Count != pageSegmentCount)
{
return;
}
// The base size of an Ogg page 27 buffer plus the number of lacing values.
size = 27 + pageSegmentCount;
int packetSize = 0;
for (int i = 0; i < pageSegmentCount; i++)
{
dataSize += page_segments[i];
packetSize += page_segments[i];
if (page_segments[i] < 255)
{
packetSizes.Add(packetSize);
packetSize = 0;
}
}
if (packetSize > 0)
{
packetSizes.Add(packetSize);
lastPacketCompleted = false;
}
else
{
lastPacketCompleted = true;
}
isValid = true;
}
private void Read(OggFile file, long file_offset)
{
file.Seek(file_offset);
// An Ogg page header is at least 27 buffer, so we'll go ahead and read that
// much and then get the rest when we're ready for it.
ByteVector data = file.ReadBlock(27);
// Sanity check -- make sure that we were in fact able to read as much data as
// we asked for and that the page begins with "OggS".
if (data.Count != 27 || !data.StartsWith("OggS"))
{
TagLibDebugger.Debug("Ogg.PageHeader.Read() -- error reading page header");
return;
}
byte flags = data[5];
firstPacketContinued = (flags & 1) != 0;
firstPageOfStream = ((flags >> 1) & 1) != 0;
lastPageOfStream = ((flags >> 2) & 1) != 0;
absoluteGranularPosition = data.Mid(6, 8).ToLong(false);
streamSerialNumber = data.Mid(14, 4).ToUInt(false);
pageSequenceNumber = (int)data.Mid(18, 4).ToUInt(false);
// Byte number 27 is the number of page segments, which is the only variable
// length portion of the page header. After reading the number of page
// segments we'll then read in the coresponding data for this count.
int pageSegmentCount = data[26];
ByteVector page_segments = file.ReadBlock(pageSegmentCount);
// Another sanity check.
if (pageSegmentCount < 1 || page_segments.Count != pageSegmentCount)
return;
// The base size of an Ogg page 27 buffer plus the number of lacing values.
size = 27 + pageSegmentCount;
int packetSize = 0;
for (int i = 0; i < pageSegmentCount; i++)
{
dataSize += page_segments[i];
packetSize += page_segments[i];
if (page_segments[i] < 255)
{
packetSizes.Add(packetSize);
packetSize = 0;
}
}
if (packetSize > 0)
{
packetSizes.Add(packetSize);
lastPacketCompleted = false;
}
else
lastPacketCompleted = true;
isValid = true;
}
