diff --git a/tools/osmpbf-outline.cpp b/tools/osmpbf-outline.cpp
index 74dfff2..63d7eed 100644
--- a/tools/osmpbf-outline.cpp
+++ b/tools/osmpbf-outline.cpp
@@ -1,11 +1,24 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <zlib.h>
+#include <netinet/in.h>
 #include <osmpbf/fileformat.pb.h>
 #include <osmpbf/osmformat.pb.h>
 
 bool is_a_tty;
 
+const int MAX_BLOB_HEADER_SIZE = 64 * 1024;
+const int MAX_BLOB_SIZE = 32 * 1024 * 1024;
+
+char buffer[MAX_BLOB_SIZE];
+char unpack_buffer[MAX_BLOB_SIZE];
+
+OSMPBF::BlobHeader blobheader;
+OSMPBF::Blob blob;
+
+bool flag = false;
+
+
 void msg(const char* format, int color, va_list args) {
     if(is_a_tty) fprintf(stderr, "\x1b[0;%dm", color);
 
@@ -37,6 +50,7 @@ void info(const char* format, ...) {
     va_end(args);
 }
 
+
 int main(int argc, char *argv[]) {
     if(isatty(2)) {
         is_a_tty = true;
@@ -46,7 +60,71 @@ int main(int argc, char *argv[]) {
         err("usage: %s file.osm.pbf", argv[0]);
 
     FILE *fp = fopen(argv[1], "r");
+    while(!feof(fp)) {
+        int32_t sz;
+        if(fread(&sz, sizeof(sz), 1, fp) != 1)
+            break; // EOF
 
+        sz = ntohl(sz);
+        if(sz > MAX_BLOB_HEADER_SIZE)
+            err("blob-header-size is bigger then allowed (%u > %u)", sz, MAX_BLOB_HEADER_SIZE);
+
+        if(fread(buffer, sz, 1, fp) != 1)
+            err("unable to read blob-header from file");
+
+        blobheader.ParseFromArray(buffer, sz);
+
+        info("BlobHeader (%d bytes)", sz);
+        info(" type = %s", blobheader.type().c_str());
+        sz = blobheader.datasize();
+        info(" datasize = %u", sz);
+        if(blobheader.has_indexdata())
+            info(" indexdata = %u bytes", blobheader.indexdata().size());
+        else
+            info(" no indexdata");
+
+        if(sz > MAX_BLOB_SIZE)
+            err("blob-size is bigger then allowed (%u > %u)", sz, MAX_BLOB_SIZE);
+
+        if(fread(buffer, sz, 1, fp) != 1)
+            err("unable to read blob from file");
+
+        blob.ParseFromArray(buffer, sz);
+
+        info("Blob (%d bytes)", sz);
+
+        if(blob.has_raw()) {
+            flag = true;
+            info(" contains uncompressed data: %u bytes", blob.raw().size());
+            if(blob.raw().size() != blob.raw_size())
+                warn(" reports wrong raw_size: %u bytes", blob.raw_size());
+        }
+
+        if(blob.has_zlib_data()) {
+            if(flag)
+                warn(" contains raw- and zlib-data at the same time");
+
+            flag = true;
+            info(" contains zlib-compressed data: %u bytes", blob.zlib_data().size());
+            info(" uncompressed size: %u bytes", blob.raw_size());
+        }
+
+        if(blob.has_lzma_data()) {
+            if(flag)
+                warn(" contains raw- and lzma-data at the same time");
+
+            flag = true;
+            info(" contains lzma-compressed data: %u bytes", blob.lzma_data().size());
+            info(" uncompressed size: %u bytes", blob.raw_size());
+
+            err(" lzma-decompression is not supported");
+        }
+
+        if(!flag)
+            err(" does not contain any known data stream");
+
+        flag = false;
+    }
 
     fclose(fp);
     google::protobuf::ShutdownProtobufLibrary();