STDMETHODIMP_(long) IDSMChapterBagImpl::ChapLookup(REFERENCE_TIME* prt, BSTR* ppName)
{
CheckPointer(prt, -1);
ChapSort();
int i = range_bsearch(m_chapters, *prt);
if(i < 0) return -1;
*prt = m_chapters[i].rt;
if(ppName) *ppName = m_chapters[i].name.AllocSysString();
return i;
}
__int64 CDSMSplitterFile::FindSyncPoint(REFERENCE_TIME rt)
{
if (/*!m_sps.IsEmpty()*/ m_sps.GetCount() > 1) {
int i = range_bsearch(m_sps, m_rtFirst + rt);
return i >= 0 ? m_sps[i].fp : 0;
}
if (m_rtDuration <= 0 || rt <= m_rtFirst) {
return 0;
}
// ok, do the hard way then
dsmp_t type;
UINT64 syncpos, len;
// 1. find some boundaries close to rt's position (minpos, maxpos)
__int64 minpos = 0, maxpos = GetLength();
for (int i = 0; i < 10 && (maxpos - minpos) >= 1024*1024; i++) {
Seek((minpos + maxpos) / 2);
while (GetPos() < maxpos) {
if (!Sync(syncpos, type, len)) {
continue;
}
__int64 pos = GetPos();
if (type == DSMP_SAMPLE) {
Packet p;
if (Read(len, &p, false) && p.rtStart != Packet::INVALID_TIME) {
REFERENCE_TIME dt = (p.rtStart -= m_rtFirst) - rt;
if (dt >= 0) {
maxpos = max((__int64)syncpos - 65536, minpos);
} else {
minpos = syncpos;
}
break;
}
}
Seek(pos + len);
}
}
// 2. find the first packet just after rt (maxpos)
Seek(minpos);
while (GetRemaining()) {
if (!Sync(syncpos, type, len)) {
continue;
}
__int64 pos = GetPos();
if (type == DSMP_SAMPLE) {
Packet p;
if (Read(len, &p, false) && p.rtStart != Packet::INVALID_TIME) {
REFERENCE_TIME dt = (p.rtStart -= m_rtFirst) - rt;
if (dt >= 0) {
maxpos = (__int64)syncpos;
break;
}
}
}
Seek(pos + len);
}
// 3. iterate backwards from maxpos and find at least one syncpoint for every stream, except for subtitle streams
CAtlMap<BYTE,BYTE> ids;
{
POSITION pos = m_mts.GetStartPosition();
while (pos) {
BYTE id;
CMediaType mt;
m_mts.GetNextAssoc(pos, id, mt);
if (mt.majortype != MEDIATYPE_Text && mt.majortype != MEDIATYPE_Subtitle) {
ids[id] = 0;
}
}
}
__int64 ret = maxpos;
while (maxpos > 0 && !ids.IsEmpty()) {
minpos = max(0, maxpos - 65536);
Seek(minpos);
while (Sync(syncpos, type, len) && GetPos() < maxpos) {
UINT64 pos = GetPos();
if (type == DSMP_SAMPLE) {
Packet p;
if (Read(len, &p, false) && p.rtStart != Packet::INVALID_TIME && p.bSyncPoint) {
BYTE id = (BYTE)p.TrackNumber, tmp;
if (ids.Lookup(id, tmp)) {
ids.RemoveKey((BYTE)p.TrackNumber);
ret = min(ret, (__int64)syncpos);
}
}
}
Seek(pos + len);
}
maxpos = minpos;
}
return ret;
}
