diff --git a/lib/imc_block.hpp b/lib/imc_block.hpp
index bea9d58..a90d8cd 100644
--- a/lib/imc_block.hpp
+++ b/lib/imc_block.hpp
@@ -13,7 +13,7 @@
 
 namespace imc
 {
-  // define "magic bytes" announcing start/end of blocks and separation within
+  // define "magic bytes" announcing start/end of blocks and separation of parameters within
   const unsigned char ch_bgn_ = 0x7c, ch_end_ = 0x3b, ch_sep_ = 0x2c;
 
   // single parameter (in a block) is determined by offset of its first/last byte
diff --git a/lib/imc_meta.hpp b/lib/imc_meta.hpp
deleted file mode 100644
index cd2dc31..0000000
--- a/lib/imc_meta.hpp
+++ /dev/null
@@ -1,48 +0,0 @@
-//---------------------------------------------------------------------------//
-
-#ifndef IMCMETA
-#define IMCMETA
-
-//---------------------------------------------------------------------------//
-
-namespace imc
-{
-  struct info
-  {
-    // timestamp of measurement
-    std::string timestamp_;
-    bool valid_;
-
-    // device and software
-    std::string origin_;
-  };
-
-  struct abscissa
-  {
-    // name of entity
-    std::string name_;
-
-    // its unit
-    std::string unit_;
-  };
-
-  struct channel
-  {
-    // name of channel
-    std::string name_;
-
-    // unit of channel's measurement entity
-    std::string unit_;
-
-    // datatype of channel
-    imc::datatype daty_;
-
-    // entity measurement depends on, i.e. channel's abscissa (mostly time)
-    abscissa channel_xaxis_;
-  };
-
-}
-
-#endif
-
-//---------------------------------------------------------------------------//
diff --git a/lib/imc_objects.hpp b/lib/imc_objects.hpp
new file mode 100644
index 0000000..2fca2e9
--- /dev/null
+++ b/lib/imc_objects.hpp
@@ -0,0 +1,84 @@
+//---------------------------------------------------------------------------//
+
+#ifndef IMCOBJECTS
+#define IMCOBJECTS
+
+//---------------------------------------------------------------------------//
+
+namespace imc
+{
+  // start of group of keys (corresponds to key CK)
+  struct group_keys
+  {
+    int version_;
+    int length_;
+    bool closed_;  // corresponds to true = 1 and false = 0 in file
+
+    // get info string
+    std::string get_info(int width = 20)
+    {
+      std::stringstream ss;
+      ss<<std::setw(width)<<std::left<<"version:"<<version_<<"\n"
+        <<std::setw(width)<<std::left<<"length:"<<length_<<"\n"
+        <<std::setw(width)<<std::left<<"closed:"<<(closed_?"yes":"no")<<"\n";
+      return ss.str();
+    }
+  };
+
+  // origin of data (corresponds to key NO)
+  struct origin_data
+  {
+    bool origin_;  // corresponds to true = 1 ("verrechnet") and false = 0 ("Original")
+    std::string generator_;
+    bool comment_;
+
+    // get info string
+    std::string get_info(int width = 20)
+    {
+      std::stringstream ss;
+      ss<<std::setw(width)<<std::left<<"origin:"<<(origin_?"verrechnet":"Original")<<"\n"
+        <<std::setw(width)<<std::left<<"generator:"<<generator_<<"\n"
+        <<std::setw(width)<<std::left<<"comment_:"<<comment_<<"\n";
+      return ss.str();
+    }
+  };
+
+  struct info
+  {
+    // timestamp of measurement
+    std::string timestamp_;
+    bool valid_;
+
+    // device and software
+    std::string origin_;
+  };
+
+  struct abscissa
+  {
+    // name of entity
+    std::string name_;
+
+    // its unit
+    std::string unit_;
+  };
+
+  struct channel
+  {
+    // name of channel
+    std::string name_;
+
+    // unit of channel's measurement entity
+    std::string unit_;
+
+    // datatype of channel
+    imc::datatype daty_;
+
+    // entity measurement depends on, i.e. channel's abscissa (mostly time)
+    abscissa channel_xaxis_;
+  };
+
+}
+
+#endif
+
+//---------------------------------------------------------------------------//
diff --git a/lib/imc_raw.hpp b/lib/imc_raw.hpp
index 27a4ac3..ebd377d 100644
--- a/lib/imc_raw.hpp
+++ b/lib/imc_raw.hpp
@@ -10,7 +10,7 @@
 #include "imc_key.hpp"
 #include "imc_block.hpp"
 #include "imc_datatype.hpp"
-#include "imc_meta.hpp"
+#include "imc_objects.hpp"
 
 //---------------------------------------------------------------------------//
 
@@ -27,6 +27,9 @@ namespace imc
     // list of imc-blocks
     std::vector<block> rawblocks_;
 
+    // check computational complexity for parsing blocks
+    unsigned long int cplxcnt_;
+
     // collect meta-information, channel definition, etc.
     imc::info imcinfo_;
     imc::channel imcchannel_;
@@ -36,17 +39,20 @@ namespace imc
 
     // constructor
     raw() {};
-    raw(std::string raw_file): raw_file_(raw_file) { this->parse_blocks(); };
+    raw(std::string raw_file): raw_file_(raw_file) { set_file(raw_file); };
 
     // provide new raw-file
     void set_file(std::string raw_file)
     {
       raw_file_ = raw_file;
+      this->fill_buffer();
       this->parse_blocks();
     }
 
-    // list all blocks in buffer
-    void parse_blocks()
+  private:
+
+    // open file and stream data into buffer
+    void fill_buffer()
     {
       // open file and put data in buffer
       try {
@@ -61,11 +67,20 @@ namespace imc
           std::string("failed to open raw-file and stream data in buffer: ") + e.what()
         );
       }
+    }
+
+    // parse all raw blocks in buffer
+    void parse_blocks()
+    {
+      // reset counter to identify computational complexity
+      cplxcnt_ = 0;
 
       // start parsing raw-blocks in buffer
       for ( std::vector<unsigned char>::iterator it=buffer_.begin();
                                                  it!=buffer_.end(); ++it )
       {
+        cplxcnt_++;
+
         // check for "magic byte"
         if ( *it == ch_bgn_ )
         {
@@ -110,6 +125,12 @@ namespace imc
 
                 // add block to list
                 rawblocks_.push_back(blk);
+
+                // skip the remaining block according to its length
+                if ( it-buffer_.begin()+length < buffer_.size() )
+                {
+                  std::advance(it,length);
+                }
               }
               else
               {
@@ -146,12 +167,26 @@ namespace imc
       }
     }
 
+  public:
+
+    // provide buffer size
+    unsigned long int buffer_size()
+    {
+      return buffer_.size();
+    }
+
     // get blocks
     std::vector<imc::block>& blocks()
     {
       return rawblocks_;
     }
 
+    // get computational complexity
+    unsigned long int& computational_complexity()
+    {
+      return cplxcnt_;
+    }
+
     // collect meta data
     void parse_meta()
     {
diff --git a/src/main.cpp b/src/main.cpp
index 816f8ed..0e00d71 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -178,6 +178,9 @@ int main(int argc, char* argv[])
       // if ( blk.get_key() == std::string("CR") )
       // for ( auto prm: blk.get_parameters() ) std::cout<<prm.get_info()<<"\n";
     }
+    std::cout<<"number of blocks: "<<imcraw.blocks().size()<<"\n";
+    std::cout<<"computational complexity: "<<imcraw.computational_complexity()
+                                           <<"/"<<imcraw.buffer_size()<<"\n";
   }
 
   // for ( std::map<std::string,imc::key>::iterator it = imc::keys.begin();