//*********************************************************
// Determines the total duration of the file (or timeshifting files)
//
//
void CTsDuration::UpdateDuration(bool logging)
{
if (!m_pFileReadBuffer)
{
m_startPcr.Reset();
m_endPcr.Reset();
LogDebug("CTsDuration::UpdateDuration() - ERROR no buffer !!");
return;
}
int Loop=5 ;
int searchLoopCnt;
do
{
m_bSearchStart=true;
m_bSearchEnd=false;
m_startPcr.Reset();
m_endPcr.Reset();
m_maxPcr.Reset();
searchLoopCnt = 2;
__int64 offset=0;
Reset() ; // Reset internal "PacketSync" buffer
if (logging)
{
LogDebug("UpdateDuration - find pcr");
}
//find the first pcr in the file
while (!m_startPcr.IsValid)
{
if (m_bStopping)
{
m_startPcr.Reset();
m_endPcr.Reset();
return;
}
DWORD dwBytesRead = 0;
m_reader->SetFilePointer(offset,FILE_BEGIN);
if (!SUCCEEDED(m_reader->Read(m_pFileReadBuffer,DUR_READ_SIZE,&dwBytesRead)))
{
return;
}
if (dwBytesRead<=0)
{
return;
}
OnRawData2(m_pFileReadBuffer,dwBytesRead);
offset += (DUR_READ_SIZE*(searchLoopCnt/2)); //Move file pointer
if (searchLoopCnt<65)
{
searchLoopCnt++;
}
else if (m_videoPid<0)
{
//failed to find a first PCR
return;
}
else
{
//Search for any PCR from the beginning again
m_videoPid = -1;
searchLoopCnt = 2;
offset = 0;
Reset() ; // Reset internal "PacketSync" buffer
}
Sleep(1) ;
}
if (logging)
{
LogDebug("UpdateDuration - found startPcr, iterations:%d offset:%d", searchLoopCnt-2, offset);
}
//find the last pcr in the file
m_bSearchEnd=true;
m_bSearchStart=false;
searchLoopCnt = 2;
offset=DUR_READ_SIZE;
while (!m_endPcr.IsValid)
{
if (m_bStopping)
{
m_startPcr.Reset();
m_endPcr.Reset();
return;
}
DWORD dwBytesRead = 0;
m_reader->SetFilePointer(-offset,FILE_END);
if (!SUCCEEDED(m_reader->Read(m_pFileReadBuffer,DUR_READ_SIZE,&dwBytesRead)))
{
m_startPcr.Reset();
m_endPcr.Reset();
return;
}
if (dwBytesRead<=0)
{
m_startPcr.Reset();
m_endPcr.Reset();
return;
}
Reset() ; // Reset internal "PacketSync" buffer
OnRawData2(m_pFileReadBuffer,dwBytesRead);
if (searchLoopCnt<65)
{
searchLoopCnt++;
}
else
{
//failed to find an end PCR
m_startPcr.Reset();
m_endPcr.Reset();
return;
}
offset += ( (DUR_READ_SIZE*(searchLoopCnt/2)) - (188*16)); //step back a few packets less than a buffer so that buffers overlap
Sleep(1) ;
}
if (logging)
{
LogDebug("UpdateDuration - found endPcr, iterations:%d offset:%d", searchLoopCnt-2, offset);
}
Loop-- ;
if(m_endPcr.PcrReferenceBase < m_startPcr.PcrReferenceBase)
{
if (Loop < 4) // Show log on 2nd wrong detection.
LogDebug("Abnormal start PCR, endPcr %I64d, startPcr %I64d",m_endPcr.PcrReferenceBase, m_startPcr.PcrReferenceBase);
Sleep(20) ;
}
}
while ((m_endPcr.PcrReferenceBase < m_startPcr.PcrReferenceBase) && Loop) ;
// When startPcr > endPcr, it could be a result of wrong file used to find "startPcr".
// If this file is just reused by TsWriter, and list buffer not updated yet, the search will operate
// in the latest ts packets received causing the start higher the end ( readed in the previous buffer )
// The only thing to do to discriminate an error and a real rollover is to re-search startPcr.
// Entering the following code with erroneous startPcr > endPcr makes an endless loop !!
// The startPcr read can also failed when it occurs between deleting and reusing the ts buffer.
// This abort the method. Duration will be updated on next call.
if (Loop==0)
LogDebug("PCR rollover normally found ! endPcr %I64d, startPcr %I64d",m_endPcr.PcrReferenceBase, m_startPcr.PcrReferenceBase);
else
{
if(Loop<3) // 1 failed + 1 succeded is quasi-normal, more is a bit suspicious ( disk drive too slow or problem ? )
LogDebug("Recovered wrong start PCR, seek to 'begin' on reused file ! ( Retried %d times )",4-Loop) ;
}
//When the last pcr < first pcr then a pcr roll over occured
//find where in the file this rollover happened
//and fill maxPcr
if (m_endPcr.PcrReferenceBase < m_startPcr.PcrReferenceBase)
{
m_maxPcr.PcrReferenceBase = 0x1ffffffffULL;
m_maxPcr.PcrReferenceExtension = 0x1ffULL;
m_maxPcr.IsValid = true;
}
}
//*********************************************************
// Seeks in the file to the specific timestamp
// refTime : timestamp. Should be 0 < timestamp < duration
//
// The method will make a guess where the timestamp is located in the file
// and do a PCR seek from there until it finds the correct timestamp
//
bool CTsFileSeek::Seek(CRefTime refTime)
{
double fileDuration=(double)m_duration.Duration().Millisecs();
double seekTimeStamp=(double)refTime.Millisecs();
//sanity checks...
if (seekTimeStamp < 0) seekTimeStamp=0;
//if (seekTimeStamp > fileDuration) seekTimeStamp=fileDuration;
//make a guess where should start looking in the file
double percent=seekTimeStamp/fileDuration;
__int64 filePos=(__int64)(m_reader->GetFileSize()*percent);
filePos/=188;
filePos*=188;
seekTimeStamp /= 1000.0f; // convert to seconds.
m_seekPid=m_duration.GetPid();
LogDebug("FileSeek: seek to %f filepos:%x pid:%x", seekTimeStamp,(DWORD)filePos, m_seekPid);
byte buffer[188*10];
__int64 binaryMax=m_reader->GetFileSize();
__int64 binaryMin=0;
__int64 lastFilePos=0;
int seekingIteration=0;
__int64 firstFilePos=filePos;
int noPCRIteration=0;
bool noPCRloop = false;
Reset() ; // Reset "PacketSync"
while (true)
{
//sanity checks
if (filePos<=0)
{
//no need to seek for timestamp 0,
//simply set the pointer at the beginning of the file
m_reader->SetFilePointer(0,FILE_BEGIN);
return false;
}
if (filePos+sizeof(buffer) > m_reader->GetFileSize())
{
//no need to seek when we want to seek to end of file
//simply set the pointer at the end of the file
m_reader->SetFilePointer(0,FILE_END);
return false;
}
//set filepointer to filePos
m_reader->SetFilePointer(filePos,FILE_BEGIN);
//read buffer from file at position filePos
DWORD dwBytesRead;
if (!SUCCEEDED(m_reader->Read(buffer, sizeof(buffer),&dwBytesRead)))
{
LogDebug("FileSeek: read failed at filePos: %x - target time: %f, iterations: %d", (DWORD)filePos, seekTimeStamp, seekingIteration);
return true;
}
if (dwBytesRead <= 0) //end-of-file
{
LogDebug("FileSeek: end-of-file at filePos: %x - target time: %f, iterations: %d", (DWORD)filePos, seekTimeStamp, seekingIteration);
return true;
}
//process data
m_pcrFound.Reset();
OnRawData2(buffer,dwBytesRead);
//did we find a pcr?
if (m_pcrFound.IsValid)
{
//yes. pcr found
double clockFound=m_pcrFound.ToClock();
double diff = clockFound - seekTimeStamp;
//LogDebug(" got %f at filepos %x diff %f ( %I64x, %I64x )", clockFound, (DWORD)filePos, diff, binaryMin, binaryMax);
// Make sure that seeking position is at least the target one
if (0 <= diff && diff <= SEEKING_ACCURACY)
{
LogDebug("FileSeek: stop seek: %f at %x - target: %f, diff: %f, iterations: %d",
clockFound, (DWORD)filePos, seekTimeStamp, diff, seekingIteration);
m_reader->SetFilePointer(filePos,FILE_BEGIN);
return false;
}
noPCRIteration = 0;
seekingIteration++;
if( seekingIteration > MAX_SEEKING_ITERATIONS )
{
LogDebug("FileSeek: stop seek max iterations reached (%d): %f at %x - target: %f, diff: %f",
MAX_SEEKING_ITERATIONS, clockFound, (DWORD)filePos, seekTimeStamp, diff);
if (fabs(diff) < 2.0)
{
m_reader->SetFilePointer(filePos,FILE_BEGIN);
}
else
{
//Set the file pointer to the initial estimate - the best we can do...
m_reader->SetFilePointer(firstFilePos,FILE_BEGIN);
}
return false;
}
// lower bound becomes valid
if( clockFound > seekTimeStamp )
{
if (filePos < binaryMax) binaryMax = filePos-1;
}
else
{
if (filePos > binaryMin) binaryMin = filePos+1;
}
lastFilePos=filePos;
filePos = binaryMin + ( binaryMax - binaryMin ) / 2;
filePos/=188;
filePos*=188;
if (lastFilePos==filePos)
{
LogDebug("FileSeek: stop seek closer target found : %f at %x - target: %f, diff: %f",
clockFound, (DWORD)filePos, seekTimeStamp, diff);
m_reader->SetFilePointer(filePos,FILE_BEGIN);
return false;
}
Reset() ; // Random jump, Reset "PacketSync"
}
else // no first PCR
{
//move filepointer forward and continue searching for a PCR
filePos += sizeof(buffer);
noPCRIteration++;
if (noPCRIteration > MAX_BUFFER_ITERATIONS)
{
if (noPCRloop) //second time this has happened
{
LogDebug("FileSeek: stop seek, no PCR found, max iterations reached (%d)", MAX_BUFFER_ITERATIONS);
//Set the file pointer to the initial estimate - the best we can do...
m_reader->SetFilePointer(firstFilePos,FILE_BEGIN);
return false;
}
//Let's try looking for any PCR pid
//starting again from the initial position
LogDebug("FileSeek: No PCR found (pid = %d), trying for any PCR pid", m_seekPid);
m_seekPid = -1;
filePos = firstFilePos;
noPCRIteration = 0;
noPCRloop = true;
}
}
}
return false;
}
