EBML updates:

- AV1 support
- Support for outputting fragments longer than 30 seconds in duration
- Fixed FireFox support for Opus audio tracks
- Added support for stdin live input of EBML
- Fixed broken timestamps when seeking in VoD EBML files
- Analyser now calculates offsets for (manual) double-checking
- Added JSON track support to EBML input and output
- Added basic input support for SRT/ASS/SSA subtitles
- Opus CODECDELAY now actually calculated.
- Fixed Opus in Firefox
- Improved MP3 support, more robust handling of corruption, support for non-standard timescale sources

# Conflicts:
#	src/output/output_ebml.cpp

src/analysers/analyser_ebml.cpp

@@ -8,6 +8,8 @@ void AnalyserEBML::init(Util::Config &conf){
 
 AnalyserEBML::AnalyserEBML(Util::Config &conf) : Analyser(conf){
   curPos = prePos = 0;
+  lastSeekId = 0;
+  lastSeekPos = 0;
 }
 
 bool AnalyserEBML::parsePacket(){
@@ -15,11 +17,18 @@ bool AnalyserEBML::parsePacket(){
   // Read in smart bursts until we have enough data
   while (isOpen() && dataBuffer.size() < neededBytes()){
     uint64_t needed = neededBytes();
+    if (needed > 1024*1024){
+      dataBuffer.erase(0, 1);
+      continue;
+    }
     dataBuffer.reserve(needed);
     for (uint64_t i = dataBuffer.size(); i < needed; ++i){
       dataBuffer += std::cin.get();
       ++curPos;
-      if (!std::cin.good()){dataBuffer.erase(dataBuffer.size() - 1, 1);}
+      if (!std::cin.good()){
+        dataBuffer.erase(dataBuffer.size() - 1, 1);
+        return false;
+      }
     }
   }
 
@@ -28,6 +37,33 @@ bool AnalyserEBML::parsePacket(){
   EBML::Element E(dataBuffer.data(), true);
   HIGH_MSG("Read an element at position %d", prePos);
   if (detail >= 2){std::cout << E.toPrettyString(depthStash.size() * 2, detail);}
+  switch (E.getID()){
+    case EBML::EID_SEGMENT:
+      segmentOffset = prePos + E.getHeaderLen();
+      std::cout << "[OFFSET INFORMATION] Segment offset is " << segmentOffset << std::endl;
+      break;
+    case EBML::EID_CLUSTER:
+      std::cout << "[OFFSET INFORMATION] Cluster at " << (prePos-segmentOffset) << std::endl;
+      break;
+    case EBML::EID_SEEKID:
+      lastSeekId = E.getValUInt();
+      break;
+    case EBML::EID_SEEKPOSITION:
+      lastSeekPos = E.getValUInt();
+      break;
+    case EBML::EID_INFO:
+    case EBML::EID_TRACKS:
+    case EBML::EID_TAGS:
+    case EBML::EID_CUES:
+      {
+        uint32_t sID = E.getID();
+        std::cout << "Encountered " << sID << std::endl;
+        if (seekChecks.count(sID)){
+          std::cout << "[OFFSET INFORMATION] Segment " << EBML::Element::getIDString(sID) << " is at " << prePos << ", expected was " << seekChecks[sID] << std::endl;
+        }
+      }
+      break;
+  }
   if (depthStash.size()){
     depthStash.front() -= E.getOuterLen();
   }
@@ -36,6 +72,25 @@ bool AnalyserEBML::parsePacket(){
   }
   while (depthStash.size() && !depthStash.front()){
     depthStash.pop_front();
+    if (lastSeekId){
+      if (lastSeekId > 0xFFFFFF){
+        lastSeekId &= 0xFFFFFFF;
+      }else{
+        if (lastSeekId > 0xFFFF){
+          lastSeekId &= 0x1FFFFF;
+        }else{
+          if (lastSeekId > 0xFF){
+            lastSeekId &= 0x3FFF;
+          }else{
+            lastSeekId &= 0x7F;
+          }
+        }
+      }
+      seekChecks[lastSeekId] = segmentOffset+lastSeekPos;
+      std::cout << "[OFFSET INFORMATION] Segment offset for " << EBML::Element::getIDString(lastSeekId) << " (" << lastSeekId << ") is " << (segmentOffset+lastSeekPos) << std::endl;
+      lastSeekId = 0;
+      lastSeekPos = 0;
+    }
   }
   ///\TODO update mediaTime with the current timestamp
   dataBuffer.erase(0, E.getOuterLen());

src/analysers/analyser_ebml.h

@@ -12,6 +12,10 @@ private:
   std::string dataBuffer;
   uint64_t curPos;
   uint64_t prePos;
+  uint64_t segmentOffset;
+  uint32_t lastSeekId;
+  uint64_t lastSeekPos;
+  std::map<uint32_t, uint64_t> seekChecks;
   std::deque<uint64_t> depthStash;///<Contains bytes to read to go up a level in the element depth.
 };