Index: trunk/Mars/mcore/FITS.h
===================================================================
--- trunk/Mars/mcore/FITS.h	(revision 17222)
+++ trunk/Mars/mcore/FITS.h	(revision 17222)
@@ -0,0 +1,122 @@
+/*
+ *
+ * FITS.h
+ *
+ * Global fits header
+ *
+ * Author: lyard
+ *
+ */
+
+#ifndef _FITS_H_
+#define _FITS_H_
+
+//#include <string>
+
+namespace FITS
+{
+
+    //Identifier of the compression schemes processes
+    enum CompressionProcess_t
+    {
+        kFactRaw       = 0x0,
+        kFactSmoothing = 0x1,
+        kFactHuffman16 = 0x2
+    };
+
+    //ordering of the columns / rows
+    enum RowOrdering_t
+    {
+        kOrderByCol = 'C',
+        kOrderByRow = 'R'
+    };
+
+
+#ifndef __CINT__
+
+    //Structure helper for tiles headers
+    struct TileHeader
+    {
+      char     id[4];
+      uint32_t numRows;
+      uint64_t size;
+
+      TileHeader() {}
+
+      TileHeader(uint32_t nRows,
+                 uint64_t s) : id({'T', 'I', 'L', 'E'}),
+                                 numRows(nRows),
+                                 size(s)
+      { };
+    } __attribute__((__packed__));
+
+    //Structure helper for blocks headers and compresion schemes
+    struct BlockHeader
+    {
+        uint64_t      size;
+        char          ordering;
+        unsigned char numProcs;
+        uint16_t      processings[];
+
+        BlockHeader(uint64_t      s=0,
+                    char          o=kOrderByRow,
+                    unsigned char n=1) : size(s),
+                                         ordering(o),
+                                         numProcs(n)
+        {}
+    } __attribute__((__packed__));
+
+    //Helper structure to simplify the initialization and handling of compressed blocks headers
+    struct BlockHeaderWriter
+    {
+        BlockHeaderWriter(const std::string& comp="") : header(),
+                                                        sequence()
+        {
+            if (comp == "" || comp == "RAW")
+            {
+                sequence.emplace_back(kFactRaw);
+                return;
+            }
+            if (comp == "SMOOTHMAN")
+            {
+                header = BlockHeader(0, kOrderByRow, 2);
+                sequence.emplace_back(kFactSmoothing);
+                sequence.emplace_back(kFactHuffman16);
+                return;
+            }
+
+            std::ostringstream str;
+            str << "Unkown compression requested: " << comp;
+#ifdef __EXCEPTIONS
+            throw std::runtime_error(str.str());
+#else
+            gLog << ___err___ << "ERROR - " << str.str();
+            return;
+#endif
+        }
+
+        void Write(char* to)
+        {
+            memcpy(to, &header, sizeof(BlockHeader));
+            memcpy(to+sizeof(BlockHeader), sequence.data(), header.numProcs*sizeof(uint16_t));
+        }
+
+        uint32_t SizeOnDisk() { return sizeof(BlockHeader) + sizeof(uint16_t)*header.numProcs;}
+
+        uint16_t Proc(uint32_t i) { return sequence[i]; }
+
+        uint16_t NumProcs() { return header.numProcs; }
+
+        char Ordering() { return header.ordering;}
+
+        void SetBlockSize(uint64_t size) { header.size = size;}
+
+        BlockHeader      header;
+        std::vector<uint16_t> sequence;
+    };
+
+#endif
+};
+
+#endif //_FITS_H_
+