Added several TS and NAL convenience functions

lib/nal.cpp

@@ -69,6 +69,56 @@ namespace nalu {
     return dataSize;
   }
 
+  const char* nalEndPosition(const char * data, uint32_t dataSize){
+    while(dataSize > 0 && memcmp(data+dataSize-1, "\000",1) == 0 ){
+      dataSize--;
+    }
+    
+    return data+dataSize;
+  }
+
+  ///scan data stream for startcode. return pointer to location when found, NULL otherwise
+  void scanAnnexB(const char * data, uint32_t dataSize, const char *& packetPointer){
+    int offset = 0;
+
+    while(offset+2 < dataSize){
+      const char * begin = data + offset;
+//      int t = ((((int*)begin)[0]) >> 8) & 0x00FFFFFF;
+      int t = (int)((begin[0] << 8)|((begin[1]) << 8)|(begin[2])); 
+      //int t = (int)((begin[0]|begin[1]) << 1)|(begin[2]); 
+      //search for startcode
+
+      //if(memcmp(begin, "\000\000\001",3) != 0){
+      if(t != 1){
+
+        //if((t & 0x0000FF != 0 )) 
+        if((int)begin[2] != 0 )                                   //XX1
+        {
+          offset +=3;
+        }else if(((int)begin[1] == 1) && ((int)begin[2] ==0)){    //X10 
+          offset +=2; 
+        }else{
+          offset++;   //[X00]? incr with 1 because the startcode could be one at 1byte offset.
+        }
+/*
+        if(t != 0 )
+        {
+          offset += 3;
+        }else{
+          offset++;
+        }
+*/
+
+//        offset++;
+      }else{
+        packetPointer = begin;
+        return;
+      }
+    }
+
+    packetPointer = NULL;
+  }
+
   unsigned long fromAnnexB(const char * data, unsigned long dataSize, char *& result){
     const char * lastCheck = data + dataSize - 3;
     if (!result){

lib/nal.h

@@ -16,4 +16,6 @@ namespace nalu {
 
   unsigned long toAnnexB(const char * data, unsigned long dataSize, char *& result);
   unsigned long fromAnnexB(const char * data, unsigned long dataSize, char *& result);
+  void scanAnnexB(const char * data, uint32_t dataSize, const char *& packetPointer);
+  const char* nalEndPosition(const char * data, uint32_t dataSize);
 }

lib/ts_packet.cpp

@@ -48,6 +48,26 @@ namespace TS {
     return true;
   }
 
+  bool Packet::FromStream(std::istream & data)
+  {
+    long long int bPos = data.tellg();
+    if(!data.read (strBuf,188))
+    {
+      HIGH_MSG("failed to read 188 bytes");
+      return false;
+    }
+    
+    if(strBuf[0] != 0x47)
+    {
+      HIGH_MSG("Failed to read a good packet on pos %lld", bPos);
+      return false;
+    }
+    
+    pos = 188;
+    return true;
+  }
+
+
 ///This funtion fills a Packet from
 ///a char array. It fills the content with
 ///the first 188 characters of a char array

lib/ts_packet.h

@@ -12,6 +12,7 @@
 #include <algorithm>
 #include "dtsc.h"
 #include "checksum.h"
+#include <fstream>
 
 /// Holds all TS processing related code.
 namespace TS {
@@ -26,6 +27,7 @@ namespace TS {
       ~Packet();      
       bool FromPointer(const char * data);
       bool FromFile(FILE * data);
+      bool FromStream(std::istream & data);
 
       //Base properties
       void setPID(int NewPID);